Do-It-Yourself (DIY)
Knee Wall



R-16 and a Radiant Reflector (with R-13 Fiberglass Batt)
R-19 and a Radiant Reflector (with R-13 Fiberglass Batt and 0.75” Furring (on Back of Knee Wall))

This application is very effective for the Do-It-Yourselfer who has decided to expand their living space by finishing out an attic or an above garage area. The benefits provided by Reflectix® are three-fold: Our product provides increased R-values by being a Reflective Insulation and also by eliminating air flow into the back side of the batt (which reduces stated R-values). The third benefit addresses Radiant Heat Flow that the wall would ordinarily absorb (a big problem for Knee Walls). The 94% + reflectivity of the product all but eliminates this heat transfer occurrence. The product has the added attraction of ease of handling and installation.

Recommended Products:
Double Reflective Insulation
Reflective/Bubble/Bubble/Reflective - Roll
• BP24025 (24” x 25’)
Staple Tab, Reflective/Bubble/Bubble/Reflective - Roll
• ST16025 (16” x 25’)
• ST24025 (24” x 25’)

Benefits:
• R-16 (with R-13 fiberglass batt)
• R-19 (with R-13 fiberglass batt and 0.75” furring (on back of knee wall))
• Reflects 94% + radiant energy back up into attic space
• Enhances performance of a typically installed system
• Increases comfort levels (by dramatic reduction in summer time heat gain)
• Installs quickly and easily

Testing and Certification:
Reflectix® 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. To obtain a copy of our Product Testing Specifications, please refer to our website “Literature Tab” above. The documents are also available by e-mail at customerservice@reflectixinc.com or call 800-879-3645.

Air Space Requirements:

Federal Trade Commission Fact Sheet: Installation Instructions:
There are 2 Methods of Installation (with varying levels of benefit)
Download DIY Knee Wall Installation Instructions 0714.pdf
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 Reflectix® 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.
• If utilizing the Reflective/Bubble/Bubble/Reflective product, staple the edge of the product to the back face of the stud, splitting the stud - 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.

2. 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 Reflectix® per instruction in Method #1 (above).

Important:

Additional Resources:
Zip Code Zone Locator
This function provides regional installation recommendations for the following applications: Attic & Cathedral Ceiling
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DIY Product Calculator Type:
Roof/Attic Application: Radiant Barrier Locate a Retailer
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*Note: This calculator is for the convenience of our customers. These recommendations are for approximate product quantity.

Video Library:

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