Insulating Knee Wall

Insulation for Knee Wall Application

Installation Instructions

Installation Instructions: (There are 2 methods with varying levels of benefit)

1. Product Installed in the Back of the Knee Wall Cavity - R-16 and a Radiant Reflector (with R-13 Fiberglass Batt)

  • Construct Knee Wall per Building Code.

  • Prior to installing fiberglass batts, measure the inside height of the knee wall cavity.

  • Precut the InfraStop® to this measured length minus 1/2”.

  • Start at the inside top of the first cavity.

  • If utilizing the Reflective/Bubble/Bubble/Reflective, Staple Tab product, staple the tab of the product to the side of the stud and continue downward stapling every 3” to 4” - Repeat on opposite stud -The plane created by the product should be parallel to the back side faces of the studs - There should be a continuous 1/2” air gap across the bottom of the cavity.

  • Install Fiberglass Batt per Manufacturer’s Instructions.

  • Install a Vapor Barrier on the inside of the Knee Wall if your Building Code dictates.

  • Finish interior of Knee Wall.

Product Installed in the Back of the Knee Wall Cavity - R-19 and a Radiant Reflector (with R-13 Fiberglass Batt and 0.75” furring (on the back of the Knee Wall)

  • Prior to placing the Knee Wall and nailing it to the floor and rafters, attach a 1”x 2” (nominal) furring strip to the back of each Knee Wall Stud.

  • Install InfraStop® per instruction in Method #1 (above).

Square Edge Roll Sizes

Thermal Insulation

Insulation for Knee Wall Application: There are 2 levels of benefit.

Product Information

InfraStop® Insulation products are a group of technologically advanced materials. They are ideal for new construction or retrofit applications in commercial, industrial, metal and post/frame buildings, along with many other DIY applications. When you think of insulation, you should think of InfraStop®. Our products are recognized for their thermal performance, easy installation, versatility, price and environmental friendliness.


  • Easy to handle and install
  • Convenient roll sizes
  • Class A / Class 1 Fire Rating
  • Inhibits dew point condensation
  • Vapor retarder (0.02 perms)
  • Does not compress, collapse or disintegrate
  • Non-toxic / non-carcinogenic

Testing and Certification

InfraStop® products are thoroughly tested at either nationally approved independent laboratories or leading universities. Tests are performed to current American Society of Testing and Materials (ASTM) standards when a standard exists. For a copy of an actual test report, please e-mail us at

  • Other Wall, Ceiling, or Crawlspace Projects

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