Energy Efficiency and Building Science News

Question & Answer: Smoke Toxicity

Wed, 2019-06-19 19:33
Energy EfficiencyGeneral Information on Smoke Toxicity:

What byproducts are found in smoke?
The combustion of products that contain organic materials produce carbon monoxide, carbon dioxide, and water. So, for example, burning common materials like wood will produce these substances. Products that contain nitrogen will also produce certain amounts of hydrogen cyanide and nitrogen oxides. Common products that contain nitrogen include sheep’s wool, silk, and composite wood products using polyurethane binders. Smoke and byproducts from fires are toxic regardless of the source of those fires and what is being burned.

What is the most abundant toxicant in fires?
Carbon monoxide (CO). In terms of hazard, carbon monoxide (CO) is typically the most abundant toxicant in fires under almost all combustion conditions. CO is also responsible for most deaths in fires.1

Are there long-term effects when exposed to smoke toxicants?
The nature and frequency of exposures to smoke toxicants will determine any long-term effects. For most people, exposure to fire gases is a single life time event, if ever. When people can escape from a fire or are rescued, they can normally recover fully after a short period of time. This may be different if people already suffer from a special or particular pulmonary disease. Certain populations may encounter fire events more frequently and require special protective devices. For example, firefighters are required to wear breathing protection when in the immediate vicinity of fires. The expectation for firefighters is that their long-term exposure to smoke toxicants is reduced through the use of personal protective equipment (PPE) and safe work practices.

Information Specific to Polyurethane Products:

What are polyurethane products?
Polyurethanes refer to a wide range of products that include flexible foams used in furniture and automobiles, rigid foams used as building insulation, durable coatings, adhesives and sealants, and even certain items of apparel.2

Can polyurethane products burn?
As with other common organic materials, polyurethane foam products are combustible when exposed to a sufficient ignition source. For that reason, to maximize their safety many polyurethane products are flame retarded or protected by a barrier that can delay ignition, retard combustion, reduce surface burning, or otherwise protect the material from fires.

Do polyurethane products emit smoke when burning?
Yes. Like any material in a fire, the amount of smoke generated is dependent on a number of factors, including the amount and type of burning material, the amount of oxygen available, and the temperature of the fire.

Do polyurethane products produce a unique toxicity risk in fires?
No. While a range of airborne chemicals may be emitted during fire events involving polyurethane products, all combustible materials produce toxic smoke when burned, including wood. In terms of hazard, carbon monoxide (CO) is typically the most abundant toxicant in fires under almost all combustion conditions. Additional combustion byproducts may include carbon dioxide, nitrogen oxides, hydrogen cyanide, and other potentially hazardous decomposition products. The composition of these chemicals, when emitted, may vary.

Do fires involving polyurethane present a significantly greater health risk than fires involving other synthetic or natural materials?
No. Smoke from a fire that involves polyurethane products does not present a significantly greater health risk than fires resulting from the burning of other synthetic or natural materials. While the combustion of polyurethane products can produce smoke containing hydrogen cyanide (HCN), it is also true that HCN is produced whenever nitrogen-containing materials are burned (e.g., sheep’s wool, silk, and wood composites). The hazards created by any burning material are strongly dependent on the fire scenario, which is a complex phenomenon influenced by a range of factors such as room size, temperature, ventilation conditions, exposure time, source, and location of ignition.3

Does the use of polyurethane foam insulation in a home present an increased risk of exposure to smoke toxicants as compared to a home insulated with other organic materials?
No. Research has shown that in a fire event the combustion of products that contain organic materials will produce similar smoke toxicants. For example, the combustion of wood and polyurethane foam insulation will produce carbon monoxide (CO) – CO is the most abundant toxicant in fires under almost all combustion conditions. It is important to remember that building fire safety codes and other protective measures like the use of flame retardants are in place to help prevent fires from starting and to provide building occupants with valuable escape time.

How are polyurethane products protected from fire?
Like other commonly used products, fire safety standards are in place to regulate the use of some polyurethane products such as construction materials, upholstered furniture, and mattresses. Some of these standards require products to pass fire safety tests and also govern how products are used. Manufacturers use a combination of fire safety technologies and product and assembly designs to meet these standards.

2 For more detailed information on polyurethanes, visit:
3 ISO TS 29761:2015 “Fire safety engineering – Selection of design occupant behavioral scenarios”- § 5.4.

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Foam-Control Plus+ 600 Provides Positive Drainage With Precise Taper and Lightweight Fill

Wed, 2019-06-19 19:19
Press Releases

When Weber State University engaged MHTN Architects to solve waterproofing problems on Stromberg Athletic Complex, everyone involved saw a valuable secondary opportunity. Rebuilding the waterproofing also provided an opportunity to replace an underutilized roof-top plaza with new Pickle Ball courts. After repairing the structural steel and integrating a new waterproofing system the team needed to think carefully about draining water off the courts and building. That’s where designers turned to Foam-Control® PLUS+ 600 insulation from ACH Foam Technologies.

Foam-Control PLUS+ 600 insulation from ACH Foam Technologies was easy to install, custom cut, and move around the job site for the construction team at Weber State.

Since the roof’s existing structural slab was sloped to drain, designers needed a lightweight, void-filler between the structural slab and the underside of the courts’ post-tensioned slab. Incorporating a two-stage system, water on the courts is shed to a center trench drain, accompanied by the waterproofing system on the structural slab and roof drains.

ACH Foam Technologies’ molded polystyrene rigid foam is a lightweight, cellular plastic material that is incredibly strong. The compressive strengths of Foam-Control® PLUS+ products range from 15 pounds per square inch (psi) all the way up to 60 psi.  With the structural slab exposed, a series of spot elevations were taken to establish the exact insulation profile to fill the void between the roof and the post-tensioned slab. Defining the thickness of each piece of foam controlled positive drainage of water off the courts without approaching structural limitations.

The Foam-Control® PLUS+ 600 platform was approximately ten-inches thick in the middle and tapered to ½” at the edges. The final deck height had to match the threshold of the plaza’s existing entry door, which couldn’t be changed, so each piece of foam across the whole roof was unique. Foam-Control® PLUS+ products are recyclable and contain no CFCs, HFCs, HCFCs or formaldehyde. Molded polystyrene costs less per R and per inch of thickness than other rigid foam insulations and Foam-Control® PLUS+’s R-Value is warrantied for 50 years.

Good architecture adds value to the people and places surrounding a project. The decisions made along the way define the results of the owner’s investment, challenging designers and builders to continually look for ways to maximize user benefits without adding expense to the project.  ACH Foam Technologies joins the project team as a resource committed to providing the most comprehensive information, service, and logistical support there is in molded polystyrene foam solutions.


Video: The WRB for Airtight, Vapor-Open Assemblies

Wed, 2019-06-19 19:11
Building ScienceEnergy Efficiency

Pro Clima’s SOLITEX MENTO 1000 is a robust, 3-ply weather resistive barrier that provides superior weather protection for insulation, plywood, OSB and exterior gypsum-board. It's extremely durable, and waterproof, outperforming conventional WRBs both in outward drying potential as well as airtightness. With its actively vapor-open, monolithic, TEEE film membrane this next generation material is our most commonly specified WRB.  SOLITEX MENTO 1000 is the robust next generation weather resistive barrier for airtight, vapor open assemblies.


Atlas Roofing Corporation Introduces Non-Hal Polyiso Insulation in ACFoam and EnergyShield Product Lines

Wed, 2019-06-19 19:02
Press Releases

Atlas® Roofing Corporation has announced the addition of ACFoam® NH and EnergyShield® NH to their current product lines. These new non-halogenated polyiso roof and wall insulation products contain no halogenated flame retardants, providing additional environmentally friendly options to their product offerings of sustainable roofing and wall insulations for architects, designers and builders.

ACFoam® NH and EnergyShield® NH product offerings are an ideal building envelope solution for projects that must meet strict specific environmental specification and customers seeking non-hal options. The Atlas® NH product lines offer a variety of benefits, including:

  • Living Building Challenge “Red List” Free, with Declare label and product database listing
  • Contribute toward LEED v4 credit requirements
  • California Department of Public Health (CDPH) VOC emissions compliant

“As a leader in polyiso manufacturing, we’re excited to introduce our non-hal technology and expand our ACFoam® and EnergyShield® roof and wall product lines,” said Greg Sagorski, Director of Technical Services of Atlas Roofing Corporation. “These new ACFoam® and EnergyShield® products provide the same great quality and performance needs customers expect, but with added benefits to meet more stringent environmental and sustainable building code goals.”

Beginning today, the following Atlas non-hal products are available:

  • ACFoam®-II NH (also available in tapered)
  • ACFoam®-III® NH (also available in tapered)
  • ACFoam®-Supreme NH
  • ACFoam®-Recover Board NH
  • ACFoam® Nail Base NH
  • ACFoam ® CrossVent NH
  • EnergyShield® NH
  • EnergyShield®CGF NH
  • Stucco-Shield® NH
  • EnergyShield® PanelCast NH

All literature and product packaging of Atlas NH products will be marked with a non-hal icon for easy and visible distinction.


Pierce Receives Cullen Award

Wed, 2019-06-19 18:56
Press Releases

Helene Hardy Pierce accepts the William C. Cullen Award. Photo by Jennifer Keegan.

Helene Pierce, F-IIBEC, VP of Technical Services, Codes, and Industry Relations at GAF, received the ASTM International William C. Cullen Award, bestowed by Technical Committee D08 on Roofing and Waterproofing. This award recognizes Pierce’s outstanding contributions and personal commitment to the field of roofing as exemplified by the distinguished accomplishments of William C. Cullen, who was also Pierce’s mentor. She is a Fellow of IIBEC (F-IIIBEC) who has served on the RCI Foundation board for nearly two decades, served on the IIBEC Interface Editorial Committee, and penned countless contributions to the journal. The award was presented by George Smith.


Improve Commercial Roof Performance With Staggered Insulation Layers

Wed, 2019-06-19 18:44
Building ScienceEnergy Efficiency

Selecting the right components for a project can dramatically improve the performance and longevity of the overall building. In a commercial roofing project, the chosen insulation and the installation technique are critical to a building’s resilience and thermal efficiency.

Photo: Hunter Panels

From a physics standpoint, energy flows from a region of high to low potential (from warm to cold). Therefore, a significant amount of heat can leave a building through an inadequately insulated roof assembly during heating season (winter) and enter a building through an inadequately insulated roof assembly during cooling season (summer). A building with an under-insulated roof assembly may require more energy to compensate for these heat gains and losses.

The benefits of installing multiple, staggered layers of rigid board insulation have been well known for years. Industry authorities, including National Roofing Contractors Association (NRCA), Oak Ridge National Laboratory (ORNL), Canadian Roofing Contractor Association (CRCA) and International Institute of Building Enclosure Consultants (IIBEC), formerly RCI, Inc., have recognized these benefits; and contractors, designers and specifiers have followed the roofing industry’s long-standing recommendation for the installation of staggered insulation layers.

Using the optimal roof insulation product also will impact performance. Polyiso insulation offers key advantages in meeting stricter building standards and improving energy efficiency. Polyiso has a high design R-value compared to XPS, EPS, and mineral wool board. Lightweight and easy to trim, polyiso can be layered to reach the desired R-values without being cumbersome to install.

Why Are Multiple, Staggered Layers of Insulation Important?

In 2015, the International Energy Conservation Code (IECC) increased the R-value requirements for the opaque thermal envelope in many climate zones across the United States. As a practical matter, most roofs will require two or more layers of insulation to meet the local energy code requirements. In the 2018 version, the IECC was updated with specific installation requirements for continuous roof insulation. The 2018 IECC explicitly calls for continuous insulation board to be installed “in not less than 2 layers and the edge joints between each layer of insulation shall be staggered” (Section C402.2.1 Roof assembly). 

Figure 1. Multiple, staggered layers of insulation can minimize air infiltration and reduce or prevent condensation in the roof system.

Staggering the joints of continuous insulation layers offer a number of benefits:

· Increased thermal performance/reduced thermal loss: The staggered joints on multiple layers of insulation offset gaps where heat could flow between adjacent boards. The staggered approach to installing insulation reduces thermal bridging in the roof assembly. A fact sheet on roof insulation published by Johns Manville (RS-7386) notes that as much as 8 percent of the thermal efficiency of insulation can be lost through the joints and exposed fasteners of installations that use only a single layer of insulation.

Photo: Hunter Panels

· Air intrusion: When conditioned air enters the building envelope, often because of pressure gradients, it carries moisture into the roofing system. This moisture will undermine optimal performance. A peer-reviewed study on air intrusion impacts in seam-fastened mechanically attached roofing systems showed that air intrusion was minimized by nearly 60 percent when the insulation joints were staggered between multiple layers of insulation. (See “Air Intrusion Impacts in Seam-Fastened, Mechanically Attached Roofing Systems,” by By Suda Molleti, PEng; Bas Baskaran, PEng; and Pascal Beaulieu,

Additionally, by limiting the flow of air and moisture through a roof system, staggered layers of insulation in a roof assembly can reduce and/or prevent condensation. The condensed moisture if allowed to remain and accumulate in the system can damage the substrate and potentially shorten the service life of a roof. A properly insulated roof can also prevent the onset of condensation by effectively managing the dew-point within the roof assembly. 

· Resilient roof assemblies: Staggered joints can reduce the stress put on a single insulation layer and distribute that stress more evenly over multiple, thinner insulation joints. For example, in an adhered roof system, the installation of multiple layers of insulation can minimize the potential for membrane splitting. In this system, the upper layer(s) of insulation can protect the membrane from potential physical damage caused by fasteners that are used to attach the bottom layer of insulation to the roof deck.

· Ponding water: Roof slope is often created through the use of tapered insulation systems. These systems offer an opportunity to stagger the joints by offsetting insulation layers and improve overall energy performance of a system. If the added insulation layer is tapered, the slope provided can improve drainage performance of the roof. Rainwater that does not drain and remains standing, collects dirt and debris that can damage or accelerate erosion of roof covering. Integrating tapered polyiso system with staggered joints into a roof’s design will not only improve the thermal performance but also can improve drainage and thus overall longevity of the system.

· Puncture resistance: Roof cover boards are commonly installed to provide a suitable substrate for membrane attachment as well as protect the roof assembly from puncture and foot traffic. When using products like polyiso high-density roof cover boards, the joints should also be staggered with the underlying roof insulation. This ensures the benefits discussed above are preserved in systems utilizing cover boards.

Installation Best Practices Are Keys For Success

A properly designed roof system that utilizes high-performance polyiso insulation products is a strong foundation (or cover) for energy-efficient and sustainable construction. However, the designed performance can only be achieved through proper installation. Implementing industry best practices such as the installation of multiple layers with staggered joints will optimize energy efficiency of the system and will help ensure that the roof system performs during its service life.  

To learn more about the benefits and uses of polyiso insulation,please visit the Polyisocyanurate Insulation Manufacturers Association website at

For more information on continuous insulation for commercial buildings, visit the Continuous Insulation website.


R25 does not equal R20+5ci Why? Thermal bridging!

Tue, 2019-06-11 20:48
Energy Efficiency

R25 does not equal R20+5ci Why? Thermal bridging! The added R5ci reduces heat loss through both the wall cavity and the framing members. A cavity insulation only wall using R29 (2x8 framing) is equivalent to R20+5ci (2x6) or R13+10ci (2x4). The effect is even greater with steel framing – steel is more conductive than wood.

  1. Thermal Bridging: Brief explanation of thermal bridging and how FPIS continuous insulation can be used in better performing walls by reducing thermal bridging. 
  2. Fundamentals of Thermal Bridging: This presentation, adapted from a presentation given by Jay Crandell P.E. at the 2018 ASHRAE Annual Conference, covers the basics of thermal bridging in wall assembly performance. It demonstrates methods of estimating the magnitude of the effect of thermal bridges using mathematical approaches to calculating assembly performance, and explains the pros and cons of various methods. 
  3. Thermal Bridging in Building Thermal Envelope Assemblies: Repetitive Metal Penetrations: Thermal bridging can significantly impact whole building energy use, condensation risk, and occupant comfort. This presentation contains an overview of the various types of thermal bridges and their impacts and a discussion of repetitive metal penetrations for cladding and component attachments. 

  4. Repetitive Metal Penetrations in Building Thermal Envelope Assemblies: The focus of this report is on uniformly distributed point thermal bridges. The main goal is to provide data to help better understand the implications and support an equitable, performance-based treatment of such thermal bridges for common building assembly conditions and variations. 

Unfortunately, thermal bridging has generally been ignored and unregulated, except as these bridges occur due to framing members within assemblies, as shown in the graphic. Unaccounted for thermal bridging can account for 20-70% of heat flow through the building’s opaque envelope. Reasonable efforts to use improved details to mitigate point and linear thermal bridges can significantly improve building envelope performance. For buildings with significant types or quantities of thermal bridges, it is generally more beneficial to mitigate thermal bridges than to increase insulation amounts.

Continuous insulation is a very efficient way to deal with thermal bridging pain.


Video: Matt Risinger Solves Thermal Bridge Issue with Innovative Wall Stud Framing System

Tue, 2019-06-11 20:33
Building ScienceEnergy Efficiency

In this video, Matt Risinger travels to Minnesota to see a house framed with an innovative wall stud framing system that solves the Thermal Bridge issue, which is a pain point to deal with when using traditional 2x wood and steel stud framing.

Please review the graphic and the following links to learn more while asking yourself which of the mitigation strategies, defined below, are deployed by this new technology:

A few ways to mitigate clear field thermal bridges include:

  • Reduce “framing factor” where structurally feasible (wider frame spacing, double stud framing, etc.)
  • Use low conductivity structural materials
  • Apply continuous insulation over structure/framing members (minimize discontinuity at floor/wall/roof intersections)
  • Mount furring over (not through) continuous insulation layer
  • Use low conductivity fasteners or devices to attach cladding, furring, etc. to framing (e.g., stainless steel, carbon fiber, etc.)

You will not want to miss this Matt Risinger video.


High-Density Polyiso Cover Boards Provide Excellent Protection

Tue, 2019-06-11 20:21
Energy Efficiency

ProtectoR HD High Density Polyiso Cover Board by John’s Manville provides excellent protection and can save time and expense for contractors. With a closed cell polyiso foam core and inorganic coated glass facers, the high-density cover board has a Grade 1 compressive strength and an R-value of 2.5.

The product offers excellent resistance to moisture, hail, wind uplift and puncture, plus its light weight makes it easy to handle.


A“Power of Two:” DuPont Performance Building Solutions Announces New Commercial Wall Warranty

Tue, 2019-06-11 20:13
Press Releases

Effective June 1, 2019, DuPont Performance Building Solutions will reinforce the trusted performance of Tyvek® Commercial products in combination with the durable thermal properties of STYROFOAM™ and THERMAX™ through the new DuPont Commercial Wall2 Ten Year Product and Labor Warranty. For qualifying projects installed using DuPont™ Tyvek® CommercialWrap® products or Tyvek® Fluid Applied WB+™, in combination either with STYROFOAM™ Brand Extruded Polystyrene (XPS) or THERMAX™ Brand Rigid Insulation on the above grade wall, the building will be protected through the “power of two” DuPont Commercial Wall2warranty.

The new DuPont Commercial Wall2 Product and Labor Warranty will include:

  • Water Hold-Out
  • Air Hold-Out
  • U.V. Exposure (before cladding installation) and
  • Up to 50 years thermal[1]

DuPont’s portfolio of solutions is designed for robust, durable product performance combined with easy, fast installation for labor savings. Our scientists and engineers recognize that durable communities rely on advanced material science with simple, reproducible installation that can be trusted time after time.

“At DuPont, we test our products and assemblies significantly above and beyond the building code requirements to develop rigorous installation details and guides that support our warranty,” said Tom Evans, Americas Commercial Director, DuPont Performance Building Solutions. “This unique combined system warranty supports our company’s strong leadership position in innovations, performance and reliability. The Commercial Wall “Power of Two” system offering is part of the first of its kind for one supplier to step up to support designers/installer/building owners with durable system solutions that protect structures for thriving communities.”

Visit us and learn more at booth 5838 during the 2019 AIA Conference on Architecture, taking place June 6-8, 2019 in Las Vegas, NV. Solutions featured include:

  •  STYROFOAM™ Brand Extruded Polystyrene (XPS) provides energy efficiency through a more sustainable insulation solution for the entire building envelope. STYROFOAM™ XPS is the original extruded polystyrene foam insulation and the first in a portfolio of products that would continue to grow and evolve to meet the needs of the building and construction industry and its related markets.
  • Tyvek® CommercialWrap® building wrap is an air and water barrier made to stand up to the rigors of commercial job sites, with high tear-strength, durability, and up to nine months of UV resistance. Tyvek® Building Envelope Solutions help make buildings more durable, comfortable and energy-efficient.
  •  THERMAX™ Brand Rigid Insulation is a polyisocyanurate rigid board insulation for interior and exterior continuous insulation. THERMAX™ products include an innovative core surrounded by a tough exterior facer of a variety of ranges and aesthetic appearance.
  •  Tyvek® Fluid Applied WB+™ is a next-generation weather barrier with Silyl-terminated polyether (STPE) technology. The Tyvek® Fluid Applied WB+™ system combines superior air/water holdout and industry-leading vapor permeability, into a membrane that provides fast rain resistance with high elongation and recovery properties on most commercial substrates.
  • Corian® Exteriors by DuPont has offered architects around the globe unparalleled design flexibility for more than a decade. Corian® Solid Surface is a highly durable and low maintenance material unique with through-body color for beautiful, yet functional exterior solutions that can be easily installed as a ventilated rainscreen system.
  • LIQUIDARMOR™ Flashing and Sealant product line is an innovative, liquid applied flashing alternative to traditional, self-adhered flashing tape. These elastomeric spray or trowel applied products form a tight, seamless barrier along the rough openings of windows and doors while helping to significantly reduce labor time.
  • The hyperefficient, high-performance FROTH-PAK™ Foam Sealant is designed to fill gaps and penetrations greater than 2” quickly and affordably, helping eliminate unwanted airflow throughout a home, ensuring customers are covered top to bottom, inside and out on every job.
  • GREAT STUFF™ Insulating Foam Sealants are specially formulated to seal gaps and cracks to block air, moisture and even pests — making it perfect for any of project needs. The GREAT STUFF PRO™ Series is designed to help pros get the job done fast, professionally and cost efficiently, providing customers with more energy efficient, comfortable homes. 
[1] Exact thermal warranty duration depends on product and assembly.

About DuPont Safety & Construction
DuPont Safety & Construction is a global leader in delivering innovation for life's essential needs in water, shelter and safety; enabling its customers to win through unique capabilities, global scale and iconic brands including Corian®, Kevlar®, Nomex® Tyvek®, Styrofoam™ Brand and Filmtec®.

DuPont™, the DuPont Oval Logo, and all products, unless otherwise noted, denoted with ™, SM or ® are trademarks, service marks or registered trademarks of affiliates of DuPont de Nemours, Inc.


Are Builders Ready for California's Switch to Net Zero?

Tue, 2019-06-11 20:02
Housing & Construction

With almost 40 million people, California is the most populous state in the nation. It’s big enough to be a country, and not a small country at that: California’s economy is the fifth largest in the world. So when California makes policy, there’s a ripple effect.

Starting in 2020, houses in California will be required to include solar panels on the roof, with the goal that the house, taking on-site power generation into consideration, will produce about as much electricity each year as it uses. The details are a little squishy, and there are some exceptions. Still, the requirement is serious, and it’s going to mean serious changes for the state’s builders.

Some builders are ready. Scottsdale, Ariz.–based Meritage Homes, for example, builds almost 2,000 homes per year in California, in addition to the thousands more it builds nationwide. The firm, which ranks No. 7 on the latest Builder 100 list, reported a total of 8,531 closings for 2018. BUILDER's sister publication, JLC, recently talked with C.R. Herro, vice president of innovation at Meritage.

“We have been building net zero for eight years,” Herro says. “We were the first big production builder to build to Energy Star, and we’ve been voluntarily building well ahead of compulsory code in California and all throughout the country for quite a while. So for us, it was a much shorter putt to get our homes to zero.”

Photo Courtesy of Meritage Homes: Solar panels on the tile roof of a Meritage home

Still, not every house Meritage builds is a zero-energy house—far from it. Even for Meritage, building every house in California to the state’s Zero Net Energy standard will be a stretch. The company buys the goal, says Herro: “Energy efficiency and renewable energy is the right financial thing to do at everybody’s price point, from entry level to luxury.” But Herro has concerns with the way the policy is being implemented. Inevitably, a zero-energy house with solar panels on the roof will cost more to buy than an existing home that was built before the mandate took effect. The houses will cost less to operate than comparable houses without zero-energy details, of course, and Herro believes the net-zero house is a better deal for the buyer in terms of the total cost of ownership. But he’s concerned that buyers won’t realize the advantages—at least, not without help.

“California and everybody else that has been pushing an energy-efficient and renewable-energy agenda isn’t enabling it," Herro explains. "What I mean by that is that they’re not differentiating the value of this energy-efficiency and renewable-energy benefit in the transaction. The evolution from my perspective is, we have to change appraisals and underwriting and possibly go to a labeling system that captures both the selling price of the home and the operating cost of the home. I consider that the true cost of ownership. That way, buyers can make more informed decisions.”

There’s a lot more to a zero-energy house than a solar array on the roof. “We put in high-performance windows, we do advanced framing details to reduce thermal bridging, we do better insulation, we do better air-sealing details, we do more efficient lighting, more efficient heating and cooling systems, more efficient water-heating systems, more efficient appliances," Herro says. "What you look at is how many kilowatts you reduce for every dollar you have to spend. And there’s a lot you do that is more financially responsible before you get to solar.

Photo Courtesy of Imery Group: A net-zero house built by the Imery Group

‘Reduce Before You Produce’

Another California builder who’s ahead of the Zero Net Energy curve is De Young Properties, based in Clovis, in the state’s Central Valley. De Young now has three developments in progress devoted to net-zero housing, all with building-integrated solar on every house. But company vice president Brandon De Young says the company followed the mantra to “reduce before you produce,” beginning with improvements—such as more efficient heating and cooling systems, higher-performing windows, and LED lighting—that could be made without changing the construction process. “My job over the last decade has been optimizing the energy-efficient features of our homes, to become the most cost-effective possible,” says De Young. “You do a lot of bidding to figure out what is the most cost-effective of all these different choices that you make.”

Changes that affect construction workflows came later in the process. “Once you’ve gotten past the low-hanging fruit, and you’re starting to have to make some important design changes in how you actually construct the home, that’s where it starts to become more challenging,” says De Young. For example, it took around two years to convert the company’s wall-framing practices from the conventional California method of 2x4 studs 16 inches on-center to an “advanced framing” system of 2x6 walls 24 inches on-center. “It involved a lot of changes in drafting, and re-engineering, and of course going through the plan submittal process with all the jurisdictions we build in, making sure that they can reapprove all the plans with the new engineering designs,” says De Young.

Trades had to learn some new practices also, such as three-stud wall corners. And at interior wall intersections with exterior walls, instead of lumber-intensive stud backing, “we went to having the interior wall stop short about a half-inch or so, about the thickness of a sheet of drywall, and then you attach that to the exterior wall by hardware up at the top plate,” says De Young. “Now that wall cavity is totally free of lumber and you can fit a whole bunch of insulation in there. You don’t have hot and cold points in the exterior wall at the intersections.”

De Young Properties also made a major change in its attic designs, switching to the “High Performance Conditioned Attic” system from Owens Corning, which involves blowing fiberglass insulation behind netting suspended from truss top chords. “In summertime around here, it can be 100°F for 30 days in a row,” says De Young, “and in the attic it can be above 140°F.” Traditionally, air conditioners and ductwork have been located in that hot attic environment, with an associated penalty for system performance and occupant comfort. The firm looked at a number of strategies for bringing the equipment and ductwork into the conditioned space. “We decided to insulate the underside of the roof and basically encapsulate the whole attic space within the thermal boundary, so that we didn’t have to mess with where our HVAC equipment goes,” explains De Young.

Like Meritage, De Young Properties strives to stay ahead of the code. “Here in California, the Title 24 energy code is what rules,” says De Young. “Every few years they update it, and it gets more and more stringent. We know we’re going to have to continually improve regardless, just to even pull a building permit." His company's attitude has been to turn the energy code into a positive, working it into its day to day and making it part of its identity. "Since 2009 or so, even our non-zero-energy homes have exceeded the code significantly," he notes.

After squeezing as much out of the home’s energy demand as it could cost-effectively manage, De Young Properties turned to the supply side: solar panels on the roof. “Our solar partner is Tesla,” says De Young. “We’ve been working with them for about six years. They help us a lot with analysis of our consumption, and then the targets that we have to try to achieve on an annual basis for solar generation. We have a wide range of home sizes—one story, two story, 1,500 square feet all the way up to 4,000 square feet—so obviously the range of solar system sizes is wide. But we are usually around 4.5 to probably 9 kilowatts, depending upon the size of the home.”

Photo Courtesy of Meritage Homes: A Meritage net-zero model home in California

Selling the Dream

All of those improvements carry advantages beyond the simple energy-bill calculation. From durability to health to comfort, advanced homes are typically better than ordinary code-compliant houses. But how to communicate that value to a home buyer? At the Department of Energy, Sam Rashkin has been working on that problem for years. Rashkin is chief architect of the Building Technologies Office in the Office of Energy Efficiency and Renewable Energy, and point man for DOE’s Zero Energy Ready Homes (ZERH) program. Homes certified under the DOE program don’t have to be actual net-zero houses—they just need to have Home Energy Rating System (HERS) ratings low enough that solar panels on the roof would be able to bring the house to net zero. So what Rashkin is selling isn’t so much a lower energy bill (although the houses do have that) as a better home, period.

The DOE program is having a national impact. In Arizona, for example, production builder Mandalay Homes—No. 171 on this year's Builder 100/Next 100 list—certifies every house under the ZERH program. “But those houses aren’t net zero,” says Mandalay chief technology officer Geoff Ferrell. “That program is just some cool details and resources, prescriptively and performance path, that help you build a fundamentally better home that is more energy efficient and has some simple details that allow the builder or a future owner to go and make it net zero by adding PV to it.”

The DOE program requires houses to comply with EPA Energy Star standards, the EPA’s Indoor Air Plus specification, and the EPA’s WaterSense program. Rashkin breaks out the elements of a certified ZERH house into six categories: advanced water-management systems; an optimized comfort system; a complete indoor-air-quality system; an optimized enclosure system; efficient components throughout the house; and a solar-ready system (meaning conduit and electrical panel pre-positioned for solar installation at a later date). Rashkin says, “The ZERH program is a way for the homeowner to get this transformational experience by simply looking for a logo.”

If only it were always that easy. Atlanta-area custom builder Luis Imery certifies most of the homes he builds as Zero Energy Ready, and he has several houses to his credit that operate at net zero or better. But he says, “Certifications, at least in Georgia, don’t sell homes. The reality of our marketplace is that it’s not an efficiency-driven or healthy-driven market at the moment. The masses are not in tune with seeing the value of owning an energy-efficient home.”

So while Imery gently steers his clients in the direction of net zero, he does it through a process that puts the customer first. “We start our projects by asking our clients one single question: ‘What is your budget for this beautiful home that you have in mind?’ And we partner with our clients early. We have a framework that we take our clients through to ultimately arrive at a plan with specs and a budget that hits their target. It’s a collaborative process instead of trying to force things that we think are great, but may be not too important to our clients. But in that initial preconstruction process, we’re weighing all the options to be as close to Zero Energy Ready as we can, if we can hit it with the client; and if we can’t, we have that conversation with the client. So, our goal is for all our homes to be Zero Energy Ready. We are 80% there.”

Imery’s latest net-zero project is a home for Mitsubishi executive Mark Kuntz near Atlanta. The home earned a HERS rating in the low 40s without on-site power; an 8.1kW, 30-panel array on the garage brought the HERS score down to -13. The construction was above code, but not extreme: staggered-stud 2x4 walls on a 2x6 plate with R3 Zip-R sheathing, wall cavities insulated with R21 cellulose, and flat-ceiling truss roofs with R50 cellulose. Triple-glazed windows were chosen at the customer’s request, although Imery says that was overkill. The blower-door test came in at about 2.6 ACH50, a disappointment to Imery (caused, he says, by a subcontractor who completed insulation work before air-sealing a few critical junctures). The home is heated and cooled by Mitsubishi mini-split equipment. The ERV is a Broan Sky Series Fresh Air System, which has controls that limit the air intake when outdoor relative humidity is excessive. For supplemental humidity control, Imery installed an UltraAire MD33 in-wall dehumidifier.

For Imery, it’s not about selling a label. “On our website, you have to drill down to find any mention of labels,” he says. But he says clients become converts as the preconstruction and construction processes continue. “We even go under contract for construction and our clients are clueless that behind the scenes, we’re making every effort to make their home DOE Zero Energy Ready,” he says. “As they commit more to the relationship with us, we slowly unveil that this house is third-party verified. What happens is that through that process, they get excited, and they want to make it DOE Zero Energy Ready. So just changing the timing of that education and conversation has helped tremendously, because they’re not getting hit by a fire hose at the beginning.”

“All our homes are third-party verified,” says Imery. “Even if [the clients] don’t want to pay for it, we pay for it because that’s the assurance to the homeowner that ‘Listen: You trusted your largest investment in your life to us, here’s our product. By the way, don’t believe only us, your home was verified by this person who came through at all these different stages of construction to verify.’”

Photo Courtesy of Imery Group: A modern-style net-zero home built by the Imery Group

The Near-Zero Home

Meanwhile, in Arizona, production builder Mandalay Homes is aiming to build hundreds of Zero Energy Ready homes at a price point that competes with lesser-performing houses in its market. “In our climate, our houses would qualify for the DOE program with a HERS rating of about 57,” says Mandalay’s Geoff Ferrell. “The way we choose to build takes us down to a HERS 47 on average, without renewables.”

So what’s different about Mandalay’s envelope? “The first thing is slab edge insulation,” says Ferrell. “We gain six or seven HERS points simply by doing a good slab edge detail.” Wall and roof insulation and air sealing also boost the score, he says. “We are insulating the walls with an inch of continuous exterior EPS foam, and then we use open-cell spray foam in our walls and our cathedralized sealed attic. And then we air seal with AeroBarrier. We are sealing all of our homes down to 0.7 ACH50 or so.”

For Mandalay, Ferrell says, the Zero Energy Ready label is a significant value in the marketplace. “It’s brand recognition,” he says. “One of the other builders in our area builds to Energy Star. To the buying public, we build the same house. These other programs help us further differentiate the things that we’ve done to make our buildings healthier, more durable, and more water resistant, and then tie that to an independent certification that validates that it’s not just talk. The house really does perform better than the other guy’s.”

With a small solar array on the roof and a power storage battery in the garage, Mandalay’s average home rates about a HERS 29, not zero—and that’s by design. Says Ferrell, “Unless a customer specifically comes in and requests it for whatever reason, we will probably never build a HERS zero home again. Because in our climate zone, with our utility not paying for exported energy, HERS zero saves the customer no more money than like a HERS 20 house would. If you don’t have net metering, like we don’t in Arizona, unless you can store and use 100% of the energy that you generate and need throughout an average year, you’re not going to get a HERS zero.”

Ferrell explains, “What a lot of the country does, because of net-metering policies, is they basically put a big solar array on the rooftop, the home uses what it can use when it can, and then when it can’t, any excess gets exported into the grid, and then the consumer gets to buy it back at a later time, non-sunny hours or whatever, on a one-for-one import-export basis. Here in Arizona, we don’t have that scenario.”

The reason Arizona doesn’t have net-metering programs that buy solar power from homeowners at full retail value is that in Arizona, there’s already too much solar on the rooftops. On sunny days, rooftop systems produce more power than the utility can use. And California is looking at a similar problem—which is why the new solar mandate in California includes a proviso about batteries. Starting in 2020 in California, if builders install battery storage systems in houses, they can cut back the amount of photovoltaics by 25%. That may not be enough incentive to push batteries into the mainstream in California, but it’s a sign that the power mix of the future is sure to include storage along with on-site generation.


Metal Panels Selected for Energy-Positive School

Tue, 2019-06-11 15:22
Building ScienceEnergy Efficiency

The new Myrtle Beach Middle School in Myrtle Beach, S.C., offers a vision of the future, in both its eye-catching design and award-winning performance. The school, like four other new elementary and middle schools opened in less than two years by the Horry County School District (HCSD), is engineered to be net-energy positive. This means the schools were designed to generate more energy than they use over the course of the year.

Photo courtesy of

Designers mirrored that top-tier energy performance in their plans for a dynamic façade, punctuated by sharp corner angles, punched-out window shading and a dramatic entrance canopy sure to attract notice from all passersby. A bold color scheme created by broad expanses of PAC-CLAD Precision Series metal panels emphasizes this strong architectural statement.

“We felt we were creating a state-of-the-art facility. We wanted to create cutting-edge architecture to emphasize the cutting-edge approach of the school,” said Derrick Mozingo, AIA, senior partner and design principal with the hometown firm of Mozingo + Wallace, which designed the floorplans and exteriors of all five new schools in the HCSD system. “You don’t go by these buildings without noticing them.”

Mozingo’s firm was a key member of the design/build team that brought HCSD’s five new schools – including two other middle schools, an elementary and intermediate school – online in only 18 months. FirstFloor Energy Positive led the effort, with SFL+A as design professionals of record and Stantec doing interior design and programing work. Panel and roofing installer Spann Roofing also was on board from the start. That company’s president, Jimbo Spann, said the fast-track schedule kept his installers on their toes.

“It was a big undertaking. There was a lot of design going on throughout the project,” he said. “There were time periods when we were working on several schools at the same time.”

In total, Spann’s team installed more than 100,000 sq. ft. of PAC-CLAD 0.40-gauge aluminum HWP panels across all five schools, with colors chosen to highlight each facility’s athletic team’s colors. Mozingo said Petersen’s PAC-CLAD product supported both his budget and his aesthetic vision for the schools.

“It created a very affordable skin, and there was no other material out there that would create that look,” he said. “It gave us a surface that would weather well and gave us that architectural ‘tech’ look we were trying to achieve. We went through a number of studies to get what we ended up with.”

Mozingo said he and his team also counted on Spann Roofing’s expertise as they went through their studies. “We have had a relationship with Spann Roofing for 30 years,” he said. “They worked with us through the design process and were a large component of that process.”

For Spann’s installers, familiarity with the product and with Petersen also were big advantages. With its responsibility for the wall panels as well as roofing for all five schools, Spann Roofing depended on the kind of responsiveness to questions and schedule demands they knew Petersen could provide.

“Petersen was very helpful, making site visits and making sure everything was going well and that we didn’t have any questions,” he said, adding that the company also was critical in helping Spann keep up with HCSD’s aggressive timeline. “That took a lot from Petersen as well, in having the material ready on time. Without the material, we could have been in a world of trouble.”

With all five schools open, Spann now has had a little time to reflect on yet another successful project with Petersen and the company’s PAC-CLAD panels. “We know Petersen very well,” he said. “They’re like us – they do high-quality work and take a lot of pride in what they do, and it’s a top-of-the-line product.”


USC Professor Innovates Smart Building Materials for New Green Deal Era

Tue, 2019-06-11 15:06
Building ScienceEnergy Efficiency

How can the skin of a building function more like human skin? Doris Sung, Associate Professor of Architecture at USC, is tackling this question by developing some innovative building materials that utilize “thermo bi-metal,” a unique, dual-alloy metal that responds to heat and cold. 

Among her innovations is a double-paned window that contains bi-metal leaves that bend and flip depending on the temperature to help regulate heat intake and output from buildings. One of Sung’s goals is to model building materials more on natural processes, materials that are active and respond to changing environmental conditions.

“Human skin is very smart,” explained Sung at her Rolling Hills workshop. “It does so many different things. It can protect you from disease and heat and cold. So, building skin, if it can do more, then the central mechanical system doesn't have to pump so hard. You don’t have to use so much energy.”

Sung started delving into smart building materials when she saw the shortcomings of the traditional passive materials normally used in architecture. Her designs have an organic, almost sculptural feel, but the principles behind them are simple.

“Using computer programs, we can make things very fluidly change and once you start doing that, [the material] starts to be able to mimic human nature and things that happen in nature a little more,” said Sung.

But when dealing with builders who see cost as a bottom line, innovative materials can seem prohibitively costly and can hamper their adoption.

“Anything new in the building industry is going to be disruptive,” said Sung. “There's also difficulty because it also has to have safety concerns, durability, cost concerns, all these things that make designing a product for the building industry quite difficult to break through.”

One of the advantages of the bi-metal window system is that it's relatively low tech, so Sung says cost is not that much more than traditional windows. 

“We don't use high technology,” Sung explained. “We don't use computer chips and the installation is actually like in a typical windows system. So, I think most people think, 'oh, wow, this is going to really add a huge cost.' But it really isn't.”

Although these materials are still in the developmental stage, Sung says there's already plenty of interest from green builders, and that these materials can be a promising player in the future of architecture.


Expanded Polystyrene Use Growing With Rise of Pre-fabricated Housing

Tue, 2019-06-04 17:51
Building ScienceEnergy Efficiency

The trendy words in the market today are “off-site construction.” Tom Walker of British Plastics and Rubber says that “One trend in the [British] construction market is the use of pre-fabricated Structural Insulated Panels (SIPS).

This method utilises a technique where sections of buildings can be made offsite and then shipped directly to the building site can be quickly craned into position and bolted together.

This significantly cuts down on construction times when compared to traditional bricks and mortar methods and therefore reduces costs of manpower and materials required during building phases.

Pre-fabricated systems typically comprise of a range of interlocking panels, each of which is effectively a sandwich of grey EPS glued between an outer and inner board materials which is specified according to the building needs.

DS Smith offers a range of EPS blocks, available in a range of size and densities.

Its EPS block is widely used in the construction industry for wall and floor insulation, as well as in the packaging sector, where parts that are simple shapes can hot wire cut to protect corners and edges.

Using EPS as part of a pre-fabricated building system can also lower CO2 emissions when transporting building components to construction sites, as EPS is an exceptionally lightweight solution to many building applications, due to it being effectively 98 per cent air.”

This point of view confirms WTCA/SBCA's Framing the American Dream (FAD) which said roughly 145 hours for the entire off-site component framing process in 1995 & then again in 2015. Please see SBCA's Framing the American Dream and Best Way to Frame websites for more information.

SBCA developed a cost calculator that further proves the dollar value of “offsite framing”. To learn more about using this calculator as a sales tool please call Jess Lohse or Sean Shields at SBCA 608-274-4849 to review it.

The following video shows in very real terms the efficiency and labor savings that  “off-site framing” can provide.

This labor savings truth was born in 1952 thru the truss plate and has grown into a manufacturing industry worth greater than the $5 billion annually today.

The future of this industry will be written by off-site framing leaders who continue to innovate until no more improvements are possible. SBCA has a large group of very intelligent members working on innovation. We'd love to have more of the best & brightest working with us to evolve the off-site framing industry into the best innovative & valuable solution it can be. SBCA members will be leading the way here and we hope for many more to join us.


Insulated Cement Board

Tue, 2019-06-04 16:53
Building ScienceEnergy Efficiency

PermaBase CI Insulated Cement Board was created to provide durability and insulation in one lighter- weight package, says National Gypsum Co. PermaBase CI combines structure, insulation, and waterproofing, reducing the number of times a crew has to circle a house to prepare the exterior for cladding. It does not purport to provide an air barrier. It’s approved for adhered veneer finishes such as manufactured and natural stone, thin brick, and tile, as well as direct-applied coatings of synthetic stucco. Prices set by distributor; expect to pay about $2.50 to $3 a square foot.


High Cost Perceived as Top Challenge in Meeting New Energy Codes

Tue, 2019-06-04 16:34
Building ScienceEnergy Efficiency

Construction costs enter the discussion during the development of all building codes. In recent years, the energy code has received particular scrutiny and criticism due to a series of substantial energy-efficient improvements from the 2006 to 2012 versions.

Adobe Stock

The International Energy Conservation Code (IECC) serves as the U.S. national model energy code and is adopted in nearly every state, except California. The IECC saw about a 30% improvement in energy savings in the 2012 version, compared to 2006.

A recent survey conducted by the Home Innovation Research Labs (HIRL) shows that cost is still top of mind for many builders when it comes to complying with the energy code. The survey, conducted in December 2018, found that 31% of the 300 builders that participated, cited cost as their top challenge in meeting the energy code.

The second most mentioned challenge was the skilled labor shortage, with 15%; followed by 14% of builders that said they had no challenges in meeting the energy code. The first response specifically addressing construction practices was “air tightness,” which was the fourth most-mentioned challenge with 10% of builders noting it.

With 14% of builders saying they have no challenges in meeting the energy code and 31% saying cost is their top challenge, this survey begs the question of why? In a LinkedIn post about the survey findings, Ed Hudson, the director of market research at HIRL, notes that many of the builders that answered “no issues” stated that they were already building beyond code minimums.

I believe there are two key factors that come into play in making cost a significant challenge when it comes to meeting energy code requirements:

  1. Size of the builder
  2. Education about energy-efficient construction practices

Larger builders, especially those included within the Builder 100, nationally, have the advantage of staff that can find the most cost effective way to comply with the energy codes where they build. These larger builders also have the benefit of being able to negotiate volume discounts with product suppliers. In addition, larger builders often have marketing staff that can help assemble a strategy for marketing the energy-efficient features of their home to prospective buyers.

One may assume that since smaller local and regional builders don’t necessarily have a staff to devote to finding the most cost effective ways that they aren’t building energy-efficient homes. That assumption would be far from the truth. In fact, many small builders are building the most innovative, energy-efficient and even net-zero homes. I would suggest that a deeper analysis of this issue will find that a lack of training and education about energy-efficient building practices as the primary reason that cost is a challenge for builders in meeting the energy code.

Although large production builders may have the benefit of staff that are trained and educated on building science, they also use trusted consultants and advisers to help them make decisions. That includes professionals that have been certified as Home Energy Raters (also known as HERS Raters) by the Residential Energy Services Network (RESNET). In fact, 81 of the top 100 builders in the U.S. used HERS Raters in 2017. With nearly 2,000 RESNET Certified HERS Raters across the U.S., builders of all sizes have access to a network of well trained and knowledgeable professionals that can help them cost effectively meet their local energy codes.

HERS Raters have the benefit of using the performance path or the Energy Rating Index path to demonstrate compliance with the energy code. This allows them the maximum flexibility in evaluating how to cost effectively comply with the code. The prescriptive path, which is the go-to compliance path for those that least understand the energy code, is typically the most expensive way for builders to demonstrate compliance because it allows little design flexibility.

survey done by the National Association of Home Builders on housing preferences asked what features are considered essential/desirable in a new home. The findings showed that energy-efficient strategies, including Energy Star appliances and windows and above-code insulation, made the most-wanted list and would positively influence the purchase decision of 80% or more of all home buyers. The Zillow Group’s Consumer Housing Trends Report found that energy efficiency was tied with preferred kitchen style, with nearly 50% of consumers desiring it in a home purchase.

These two surveys show that energy-efficient construction is quickly becoming an expectation of home buyers. Builders that are struggling to comply with energy codes need to work with energy efficiency professionals, like HERS Raters, to quickly understand the most cost effective means to meet energy codes and build an efficient home.


SIKA Continues to Grow Its Construction Products Business

Tue, 2019-06-04 16:22

Sika has completed the acquisition of Parex on May 23, 2019. The deal was announced on January 8, 2019. With annual sales of CHF 1.2 billion, Parex is a leading mortar manufacturer with an impressive track record of profitable growth and attractive margins. Sika and Parex are two strong companies that are highly complementary in product offering and channel penetration. With this acquisition, Sika will expand its product portfolio for the building finishing market, further strengthening its world leader position in construction chemicals, and reaching sales in excess of CHF 8 billion for 2019.

Parex’ product offering includes facade mortars, tile adhesives, and waterproofing mortars. With its expertise in mortar solutions for renovation and new builds, Parex participates in all phases of the construction life cycle. Parex has a particularly strong presence in distribution channels, especially in China, where Parex has built up a network of over 90,000 points of sale. With its strong, recognized brands, Parex is known for its comprehensive R&D expertise and technical excellence. The company is locally present in 23 countries, with key positions in 8 core markets, and operates 74 plants around the world.

The acquisition of Parex will strengthen Sika’s growth platform. Its mortar business, which is a key growth technology for the group and one of its important earning contributors, will more than double in size to CHF 2.3 billion. Parex’s strong position in distribution channels will open up new business opportunities for Sika’s product range. Parex will gain access to Sika’s well established direct sales channels, and Parex’s expertise in the facade and tile setting business will allow Sika to participate in these growing and attractive market fields.

Paul Schuler, CEO of Sika: “With the acquisition we are bringing together two strong companies. Parex’ and Sika’s joint business activities present an excellent growth platform for both organizations. In addition to the highly complementary fit with regard to product offerings and channels, we also see that Parex and Sika have very similar culture, values and management styles   ̶   with the focus on customer orientation, empowerment, high-quality products and services. The integration planning is well on track, and on-site visits have confirmed the attractiveness of the combination of the two businesses. We are excited to start working together to build our joint successful future. We warmly welcome all employees of Parex to the Sika Family.”

Eric Bergé, CEO of Parex: “I am very proud of what we have achieved. I want to thank the entire Parex team worldwide for their outstanding work. The months spent together with Sika to prepare this day showed how much these two great teams can bring to each other. We can look to the future with confidence.”

Sika continues to grow its business in the construction market segment. For more information see the following links:

  • Being the market leader in PIR insulation technology for over 37 years, Rmax manufactures industry-recognized and ANSI code compliant insulation materials and accessories that are widely used all over the U.S.
  • Sarnafil has been developing and producing high-quality thermoplastic roofing membranes and system solutions for new building and renovation projects since 1962.
  • Liquid Plastics hold a significant market position in liquid membranes for roofing and waterproofing applications by joint sealing and concrete repair and protection. The membranes are used mainly for restoration for small to medium sized roofs.
  • May National Associates, Inc. is a leading manufacturer of silicone and polyurethane products for sealing and bonding. Manufacturers and markets a full range of silicone, polyurethane, hybrid, and acrylic sealants and adhesives.
  • Sikalastic membranes provide very reliable edge-to-edge waterproofing systems and flashing membranes for a multitude of smaller-scale applications.
  • Sika offers a full line of professional grade (Pro Select) specialty construction products for residential projects.
  • Roofing and waterproofing products protect buildings from weather conditions in all types of climates. 


The Pathway to High-Performance Buildings

Tue, 2019-06-04 16:01
Building ScienceEnergy Efficiency

Editor’s Note: Building envelope issues impact multiple performance issues in a building including HVAC performance, building pressures and increase the risk of moisture intrusion. If a properly design building envelop system is correctly aligned with thermal, air and moisture control layers problems from moisture intrusion, poor indoor air quality and comfort complaints are reduced. Missing details, incorrectly placed barriers, disconnects in the continuous systems are all common design considerations that will impact the building performance for years to come. Sealants or transition materials may not be specified correctly at intersections of components or there might be missing sealant requirements for penetrations by fasteners when installing cladding or bracing for exterior shading. Wall sections may promote thermal bridging, which is the unrestricted movement of heat through the wall section. This leads to excessive energy leakage and lost cost. The Continuous Insulation website was built to help provide the science behind details, like energy performance, transition detailing, WRBs, thermal bridging and so forth.

The term commissioning, referred to as Cx by the pros, is a process for new and existing buildings that ensures the systems and components in a building are designed, installed, tested, operated and maintained according to the operation requirements of the owner or final client. The commissioning process can improve the efficiency of the equipment and systems to prevent issues from construction, installation and maintenance negatively impacting the performance and energy usage over the lifespan of a building. Through a systematic evaluation of the buildings designed and implemented systems, the commissioning process formalizes review and integration of all project expectations during planning, design, construction and occupancy phases by inspection, functional and performance testing, and oversight of operator training and record documentation.

When assessing the benefits, barriers, opportunities and savings that encompass the commissioning process, who better to ask than a working industry professional with over 15 years’ experience in the field? In this Q&A session with NCBPA Board Chair and building scientist, Meghan McDermott of High-Performance Building Solutions, we will discuss the benefits, goals, setbacks and industry trends of all things Commissioning.

The Benefits of Pursuing Building Commissioning

Commissioning is an all-inclusive, quality assurance-based process working with project and operation teams which document the planning, delivery, verification, and managing risks to functions performed in, or by, buildings. Commissioning also helps to maximize energy efficiency, extended performance, and ensure environmental health and occupant safety. The process also improves indoor air quality by making sure the building components are working correctly and that the plans are implemented efficiently and effectively. Commissioning reduces operating costs while delivering preventive and predictive maintenance plans, tailored operating manuals and training procedures for all users to follow.

Meghan McDermott: "The main benefit of pursuing whole building commissioning is that there is an independent third party reviewing the design, construction and O&M of a building to ensure the overall performance meets the owner’s requirements. The process ensures the owner is getting what they need and want within their budget, hopefully without costly change orders once construction starts. Catching missing items or deficiencies in the design phases reduces the likely hood of costly changes during construction or worse when the building is completed and occupied."

Goals to Accomplish in Each Project

There are various goals associated to differing projects and building types, but generally, once setting a Commissioning scope, budget, plan and schedule, the overall goal is to deliver buildings and construction projects that exceed or meet the owner's project requirements (OPR). Once a project undergoes commissioning, there are opportunities to prevent or eliminate problems inexpensively through proactive quality techniques, verify systems that are installed and working correctly and benchmark those correct operations.

When reviewing the final commissioning report, a major goal, which is almost always accomplished, is to lower overall first costs and life-cycle costs for the owner. Providing documentation and records on the design, construction, and functional and performance testing can facilitate ongoing operation and maintenance of the facility—this can be done by implementing trend logs and various automated Cx tools to enable the Operations and Maintenance (O&M) process. With these Cx goals and others, the important deliverable is to maintain performance for the entire life cycle of the building.

Common Barriers Found in the Commissioning Process

Every new and existing construction project is unique, but many of the same design and construction issues arise from time and time again. Commissioning and the efforts involved are focused on avoiding these reoccurring issues, and in many cases the fee building owners pay for commissioning is paid back by the costs avoided detecting and resolving issues early, for a new construction project, for example. Many of the issues below are fairly easy to correct or plan for and, as many experts know, without commissioning involvement, new building projects are delivered without these types of issues ever being corrected.

  1. Mechanical equipment sequences of operation: Frequently, sequences of operation in mechanical design documents create conflict between systems or could be unclear to installers and controls contractors. At times, they are missing entirely from the design documents and do usually not integrate energy savings operations.
  2. Missing mechanical equipment in design documents: Missing mechanical system equipment in the design documents, such as mini-split systems serving IT closets, exhaust fans, dampers, access panels, and valves, is common upon walkthroughs.
  3. Electrical circuits not sized appropriately for loads: It is important for Cx agent to inspect circuit capacity and comment when the design includes loads larger than circuit components can accommodate, or when circuit components are oversized significantly, and financial savings are available by reducing components to a more appropriate size.
  4. Building enclosure infiltration: Enclosure issues can impact multiple performance issues in a building including HVAC performance, building pressures and increase the risk of moisture intrusion issues. If a properly design building enclosure system with correctly aligned thermal, air and moisture control layers are not problems included from moisture intrusion, poor indoor air quality and comfort complaints are common. Missing details, incorrectly placed barriers, disconnects in the continuous systems are all common design issues that will impact the building performance for years to come. Sealants or transition materials may not be specified correctly at intersections of components or there might be missing sealant requirements for penetrations by fasteners when installing cladding or bracing for exterior shading. Wall sections may promote thermal bridging, which is the unrestricted movement of heat through the wall section. This leads to excessive energy leakage and lost cost.

Meghan McDermott: "The main barrier to building enclosure commission (BECx) is lack of understanding of the process and fears that the cost is too expensive. Several building owners I have talked to have asked their team about including building enclosure commissioning and it has been scrapped because of cost. When I investigated the cost estimates, they were including all of the performance testing in the NIBS guide instead of just the performance testing that was beneficial to the owner. As with any commissioning project the main objective is to follow the Owner’s Project Requirements (OPR), if the owner wants to do just a few performance tests related to the enclosure that is fine; there is no need or budget to cover all the performance tests listed in NIBS."

Preventing Barriers

Gather installed technology manuals, drawings, specs, and other documents before starting commissioning process – it is difficult to locate documents at manufacturers resources or websites. Ensuring that the building is prepped and there are set times for operating is critically important, keeping to a schedule and keeping track of daily changes will add up to significant positives that will likely not delay the project. Understanding the most frequent commissioning issues documented in both the design and construction phases of new or existing building commissioning projects can give building owners and managers a leg-up on ensuring these issues are resolved quickly and efficiently.

Meghan McDermott (A): "For the BECx discuss with the Owner at the beginning the reason they want to include BECx in their project. Many times, during the discussion you will find they have had specific issues in their existing building inventory. The Owner will be able to provide insight into what performance testing is critical to their needs; include performance testing that will address the issues from previous projects and where common failures occur, not everything in the NIBS guide."

Trends in the Cx Industry

Meghan McDermott (A): "LEED Version 4 including Building Enclosure Commissioning credit instead of just getting an Innovation in Design credit will likely increase the number of projects we see pursuing building enclosure commissioning."

The Commissioning process has been practiced for years but has been required and marketed in various ways. Historically, voluntary green building certification standards have been the primary driver for Cx standards, specifically for LEED and ENERGY STAR building certifications. Green building certifications have their own set checklist of requirements that the Cx agent must complete to obtain the credit or compliance for that specific project. Although, with a wider and advancing market growing for green building across the U.S., sustainability goals, building codes, and utility incentives have been implementing required Cx standards into state-wide building codes and utility incentives.

For example, a successful market-based policy measure known as commercial building benchmarking has been making its way across the U.S. for several years and is becoming more and more popular. Several states such as California, Washington and Maryland have adopted commercial building benchmarking laws which vary from state-to-state. With the energy code being implemented across various states and mandates such as benchmarking laws are becoming more and more popular, the push for Cx will not only become good practice, but will be required for testing and maintaining optimal building performance.


Buildings at Risk, Like Grenfell, Typically Have a Compliance Flaw

Tue, 2019-06-04 13:06

A recent article states the following as fact, where words are highlighted so that these comments can be evaluated by the reader:

  • When fire broke out at Grenfell Tower in London, the flames were whisked through the 24-story structure with astonishing speed……
  • Outrage spread quickly when Britons learned the cheap cladding that shrouded the tower had turned it into a death trap……

Nearly two years after the Grenfell fire in June 2017, this is what we found of the government’s efforts, which have left tens of thousands of people at risk:

  • About 16,000 private apartments are still wrapped in the kind of exterior cladding that fed the Grenfell fire.
  • Their owners feel trapped in tinderboxes they cannot sell, and some residents have felt compelled to join round-the-clock patrols of their buildings, always on guard for a spark or whiff of smoke.
  • The government did move fairly quickly to strip the dangerous cladding from public housing towers, but people in approximately 8,400 public apartments await a full repair.
  • Many of the business-friendly regulations that allowed Grenfell to be built on the cheap remain in place, despite a promise to rethink them top to bottom.
  • The government has been slow to look at other types of flammable coverings that may be putting at least 340 additional apartment towers in danger.
  • A year before the fire, contractors re-clad Grenfell Tower with a form of low-cost aluminum paneling. The cladding was banned in the United States and many European countries because if a fire breaks out, it allows the flames to spread quickly.
  • But English building rules were more lenient. As long as the cladding’s surface — the aluminum — was nonflammable, it mattered less what was inside. In this case, that meant a middle layer of plastic that amounted to a sheet of solidified fuel.

This begs a rhetorical question, is this Sargent Friday’s “just the facts ma’am”, or is this journalism of another type? Thoughts?

The goal of professional journalism is to provide well-referenced facts and allow a reader to be discerning via their intellect. Here is a short list of more than 30 readily available articles, which provide key known facts:

  1. Grenfell BRE Report: If Code Followed, Likely Wouldn't Have Happened A Building Research Establishment (BRE) report summarizing the investigation into the deadly Grenfell Tower fire last year in London has been leaked, and several causes for the tragedy were identified. Each of the following excerpts from the report are linked to the online report.
  2. Would Smoke Alarms and Sprinklers Have Saved Grenfell's Installed Cladding? According to news reports since the fire, it seems it spread cladding that was applied to the building as part of a refurbishment completed last year
  3. London's Grenfell Fire: Will Plastics Be Inappropriately Blamed? At least 58 people are dead, or presumed dead, after a huge fire raged through the night at a west London 24-storey tower block called Grenfell Tower.
  4. Post Grenfell, Do You Know the Code and Your Cladding Options? Given recent concern over combinations of foam plastic insulated sheathing (FPIS) with different types of cladding since the Grenfell Tower fire, it is worth taking a specific look at both the extent of cladding options available with FPIS and the important restrictions.
  5. Grenfell Fire Should Not Spur Code Changes in the U.S. Just over a year ago, a fire in London’s Grenfell tower killed 72 people and had building industries around the globe taking a closer look at fire protection. However in America, what happened to Grenfell is unlikely to occur because a building like Grenfell would not have been built in the first place.
  6. ICC Provides Perspective on Combustible 'Cladding Systems' This short article by the International Code Council briefly discusses the 2018 International Building Code (IBC) requirements in terms of fire safety and what to look for in plan review and inspections when cladding is used on a noncombustible wall.

  7. NFPA 285 and Code Conforming Design – Reliable or Not? The evidence supporting the effectiveness of NFPA 285 is very strong. Moreover, history bears out this conclusion as found in this report sponsored by DuPont.

Building Research Establishment (BRE) report summarizing the investigation into the deadly Grenfell Tower fire last year in London, and several causes for the tragedy were identified. The report states that Grenfell Tower as originally constructed provided “very high levels of passive fire protection,” but that a refurbishment undertaken between 2014 and 2016 was not performed correctly, and opened multiple avenues for fire spread, in the event of an accidental fire.

Essentially, the report makes clear that had the refurbishment been completed to code, it is highly unlikely the fire would have spread beyond the original flat nor would there have been any loss of life. 

Between 2014 and 2016, Grenfell Tower received a new cladding and insulation system as part of a refurbishment.  The BRE report notes that both the insulation and the aluminum composite panels used provided combustible fuel for the fire. These materials have been used successfully for many years, and when installed in a code-compliant manner, are properly separated from living spaces and use detailing to prevent the spread of the fire inside the wall to the next higher floor.

In the case of the Grenfell Tower refurbishment, however, key details were ignored which allowed the fire to reach the cladding, and once there, to spread without check.  New windows were installed in a way that “lacked any barriers to fire spread between flats and the cladding system” and cavity barriers in the cladding system meant to expand to block off the cavity during a fire were too small to expand fully, and in many cases, improperly installed. 

Click to enlarge.

These shortcomings allowed the fire to easily move from interior living space to the exterior façade (and vice versa), and spread quickly across the façade. Fortunately, when buildings similar to Grenfell Tower are constructed in the U.S., they are subject to the International Building Code (IBC). Building code requirements in the United States are different from those used to construct Grenfell Tower. It is clear from the report’s conclusions that enforcement of the code is the most effective way to prevent similar occurrences in both the U.S. and U.K.

With limited exceptions for some one-story buildings, Chapter 26 of the IBC requires buildings of type I-IV construction of any height which contain foam plastic insulation to comply with National Fire Protection Agency standard 285 (NFPA 285).  To comply, testing and professional engineering analysis are performed where the proposed wall and cladding system is subjected to fire exiting from a window (as happened with the Grenfell Tower). To pass, fire tests and related professional engineering analysis must show that fire spread vertically or horizontally along the cladding beyond the immediate area is less than the time it would take for the inhabitants to evacuate (i.e. the NFPA measurement of this concept is ten feet of vertical and five feet of horizontal flame spread away from the window opening during the 30 minute test.)

Given the report’s conclusions regarding the construction detailing and the resulting spread of fire in the Grenfell Tower event, a key questions is: “Does this event reflect expected fire resistance performance, in code compliant construction, in a way that should cause significant regulatory changes for U.S. buildings?”  

It is clear, if designers, builders and installers perform in a manner that conforms with the requirements of the IBC, the 30 years of demonstrated effective and safe performance, when using NFPA 285 and IBC Chapter 26, will continue.


Does APA have a Design Value and QC Conflict of Interest?

Tue, 2019-06-04 11:06
Building Codes

APA the Engineered Wood Association is a market development organization for structural engineered wood products manufacturers. APA says they are focused on engineered wood developments, yet when a highly engineered wood fiber composite product has more favorable market performance characteristics, engineered wood is “not so good.”

Graphic 1: APA’s public home page providing its perspective on a sister highly engineered wood fiber composite product. Why would they denigrate another wood fiber product? Click to enlarge.

For commodity products like OSB, market promotion is largely APA brand focused. The approach taken includes the following examples:

  1. APA’s Wall Bracing Calculator
  2.  “Value Engineering
  3. Sustainable Buildings, Sustainable Future

These are all tools to promote OSB use created and published by APA. At the same time APA also serves as a third party inspection agency for OSB manufacturers. What is more important to APA, sales or QC? What would happen in most companies if the QC department reported to the sales/marketing department?

To further strengthen these marketing efforts, APA publishes reports critical of competitive products in order to advance the sales of APA-branded commodity OSB.

  1. Takeaways from 2015 Texas Tornadoes
  2. Texas Tornado Damage Assessment Report
  3. Resilient Construction

conflict of interest
n. a situation in which a person has a duty to more than one person or organization, but cannot do justice to the actual or potentially adverse interests of both parties. This includes when an individual's personal interests or concerns are inconsistent with the best for a customer, or when a public official's personal interests are contrary to his/her loyalty to public business. An attorney, an accountant, a business adviser or realtor cannot represent two parties in a dispute and must avoid even the appearance of conflict. He/she may not join with a client in business without making full disclosure of his/her potential conflicts, he/she must avoid commingling funds with the client, and never, never take a position adverse to the customer.

These all seem like relevant “marketing association” activities and pretty straight-forward, until you consider the following observations, which point to at the very least, an appearance of a series of conflicts of interest that seem to bias objectivity:

  1. APA does market development, and the APA brand is the key to market development.
  2. APA gets paid by the manufacturers of OSB to do this market development and to further build the APA brand.
  3. APA gets paid by the manufacturers of OSB, through its IAS ISO/IEC 17020 quality auditing program (IAS accreditation number AA-6), to perform the manufacturer’s 3rd party inspection of product quality and maintain the OSB design values used in the market. All of this maintains OSB competitiveness.
  4. APA is accredited by the Standards Council of Canada (SCC) as an ISO/IEC 17065 product, process and service certification body and “ICC Report” writer (SCC File # 10012).
  5. Through these accreditations, APA provides certification to clients that conform to product standards as well as APA policies. All APA manufacturers are subject to ongoing audits of the client’s quality system, internal inspections and conformance to the product standard.

What would happen in most companies if the QC and engineering departments reported to the sales/marketing department?

  1. APA also gets paid by the manufacturers of OSB to create and publish the OSB voluntary product standard for producing a quality product and associated design values for OSB use in the market. As APA states:

 “APA has a long and extensive history in building codes and standards development activities. It serves, for example, as the secretariat for the standing committees of U.S. Product Standard PS 1 for Structural Plywood, the consensus softwood plywood standard, and Voluntary Product Standard PS 2, the U.S. harmonized performance standard developed under the U.S.-Canada Free Trade Agreement. APA has developed performance standards over the years for numerous products, including, for example, plywood siding, wood structural panel sheathing, structural glued laminated timber (glulam), wood I-joists, rim board, and cross-laminated timber. APA issues APA Product Reports designed to help manufacturers expedite market entry of their products.”

  1. Finally, APA gets paid by the manufacturers of OSB to advocate during the building code creation process to ensure the code remains favorable to OSB. As stated in a 2016 newsletter “APA and Coalition for Fair Energy Code staff attended the International Code Council Group B Committee Action Hearings for the 2018 International Fire Code (IFC), International Building Code (IBC) – Structure, in Louisville Kentucky in April (April 17 to 27 2016) ……. Among 22 APA change proposals, 16 were approved. None of the disapproved APA proposals are considered critical to the acceptance or market access of APA member’s products….” Contact BJ Yeh for more information.

Click to enlarge.

Maybe all of this is best defined by the leadership of APA themselves in the following set of articles that show there is a very strong desire to create OSB competitive advantage by whatever means necessary:

  1. Wood Structural Panel Lateral Capacity? APA - “Not Sure”
  2. APA - IRC Allowable Design Values for OSB Wall Bracing = 175 PLF 
  3. Competition Improves Everyone; APA Disagrees 

Graphic 1 SBCA proposed IRC code change proposal to fix OSB design values to be in alignment with the APA-BSSC report stands  undisputed by APA and has been confirmed by SBCA/SBCRI testing.

Clearly, given all of the information above and the APA letters found in PDF form below, APA does not appear to be unbiased in their approach to OSB design values, third party quality assurance and promotion of OSB in the market.

A question that has been asked is how hard would it be for a plaintiff’s lawyer in a construction defect case involving OSB to establish an APA conflict of interest with the facts provided herein?

Please review and send us your point of view with respect to these facts and if you were on a jury what your decision would be?

PDF Reference Links

For additional information on the performance of wood structural panels, please visit the following webpage on OSB as a Raw Material and the following articles on performance of building materials in high winds and as tested.