The yield limit equations specified in the National Design Specification® (NDS®) for Wood Construction for bolt, lag screw, wood screw, nail, spike and drift pin connections represent a mechanics-based approach for connection design. This approach, which was incorporated in the 1991 NDS, permits the designer to determine effects of member thickness, member strength, fastener size, and fastener strength on lateral connection values for the majority of connections found in wood construction.
Improved energy efficiency is a major focus in building design and construction with the evolution of the International Energy Conservation Code (IECC). Foam plastic insulating sheathing (FPIS) is one of many products used, due to its beneficial thermal performance values, used alone or in combination with conventional sheathing and between the studs insulation.
Changes in the International Energy Conservation Code (IECC) from 2009 to 2012 have resulted in an increase in minimum insulation levels required for residential buildings. Not only are the levels increased, but the use of exterior rigid insulation has become part of the prescriptive code requirements. With more jurisdictions adopting the 2012 IECC, builders will be required to incorporate exterior insulation in the construction of their exterior wall assemblies.
The addition of insulation to the exterior of buildings is an effective means of increasing the thermal resistance of both wood framed walls as well as mass masonry wall assemblies. For thick layers of exterior insulation (levels > 1.5 in.), the use of wood furring strips attached through the insulation back to the structure has been used by many contractors and designers as a means to provide a convenient cladding attachment location.
When insulating a steel-framed exterior wall in cold climates, it is usually necessary to provide continuous insulation on the exterior of the studs to reduce the effect of thermal bridging. As energy codes continue to become more stringent, the thickness of the continuous installation has increased. The increased insulation thickness, however, introduces several problems for building designers, such as window and door jambs needing to be extended, siding manufacturers’ warranties being voided when more than one inch of continuous insulation is used, and heavier siding products causing fast
General do’s and don’ts for the installation of FPIS.
An Introduction, Overview and Outline for the Code-Compliant & High Performance Walls presentation.
Concerns regarding moisture control performance can affect walls of any thickness, with or without the added protection of exterior continuous insulation. One purpose of this Research Report is to present data to evaluate and substantiate an appropriate application of continuous insulation in an R20+5 assembly (e.g., R20 cavity insulation plus R-5 continuous insulation on the exterior).