When it comes to walls, the use of continuous insulation can greatly improve performance and simplify design and installation.  In particular, foam plastic insulating sheathing (FPIS) products can serve as an air barrier, water resistant barrier, water vapor control/retarder, and cut down on the detrimental effects of thermal bridging.

Tools & Education

Attachment of Exterior Wall Coverings Through Foam Plastic Insulating Sheathing (FPIS) to Cold-formed Steel Wall Framing Report

Cladding installation through foam sheathing used in light frame steel exterior wall applications. Available as a sealed code compliance report. 

Water, Water Everywhere and Not a Drop to Drink: Practical Building Science to Keep Walls Dry

This session, presented at IBS 2017, provides actionable prescriptive guidelines for integrated insulation and vapor control strategies. 

Foam Plastic Insulating Sheathing Used as an Air Barrier Material in an Air Barrier Assembly Report

This research report provides a central location for the identification of foam sheathing products that have been approved for use as an air barrier material in an air barrier assembly. Available as a sealed code compliance report. 

Break it, or Lose it: Thermal Bridging in Building Envelopes

Details and information on the use of CI to avoid thermal bridges

Thermal Bridging in Building Thermal Envelope Assemblies: Repetitive Metal Penetrations Presentation

Discusses types of thermal bridges and their impacts as well as repetitive metal penetrations for cladding and component attachments. 

Best Practices

NFPA 285 Testing and the Use of Engineering Extensions in Wall Assemblies Using Foam Sheathing

Foam plastics used in buildings of Types I-IV construction require an assessment of their ability to resist vertical and lateral flame spread. Determine if your assembly is required to comply with NFPA 285 Fire testing with this design guide.

BSI-120: Understanding Walls*

In August 2004, the ASHRAE Journal ran Joseph Lstiburek's paper enttitled “Understanding Vapor Barriers.”  After almost two decades, he has updated it to focus on rain and air control as well as vapor control – all things that “walls” need to do – hence the revised title, “Understanding Walls.”

Practical Research

Assessment of Water Vapor Control Methods for Modern Insulated Light-Frame Wall Assemblies Research Report

A comprehensive assessment of the state-of-the-art of water vapor control for modern, code-compliant, light-frame wall assemblies.

Cladding Attachment through FPIS Research Report

Overview of current knowledge supporting the attachment of cladding through foam sheathing used in exterior wall assemblies to comply with the 2015 editions of the International Building Code (IBC) and the International Residential Code (IRC).

Development of Thermal Bridging Factors for Use in Energy Models

This work provides practical guidelines for the mitigation and reduction of thermal bridge problems in existing and new Army facilities. A wide range of building types was investigated from which nine common types were identified, and a number of important thermal bridge details were chosen for each.

Thermal Performance of Façades

This investigation seeks to quantify the effects of thermal bridging in commercial facades and then propose alternative solutions to improve performance by comparing infrared images of recently completed buildings to theoretical models. 

Model Moisture Control Guidelines for Light-Frame Walls: A Building Code Supplement for Builders, Designers, & Bldg Officials

This Research Report provides actionable guidelines to effectively consider, evaluate, and manage the balance of wetting and drying potential in common above-grade, light-frame wall assemblies in a broad range of climate conditions.

Additional Information

Movement of Cladding Attached through FPIS - DOE Report

Research findings on the long-term performance of cladding attachments through foam sheathing. Covers fastening techniques, material expansion and contraction, and deflection (creep). 

Polyiso - Commercial Walls

Information on the use of Polyiso in commercial wall applications

XPS - Commercial Walls

Information on the use of XPS in commercial wall applications

EPS - Floors, Walls & Ceilings

Information on the use of EPS in wall applications