Post Frame Building - Product: Reflective One Side
Post Frame Building - Roof - Retrofit - Bottom of Truss

Bottom of the Trusses
Open Interior
R-6.6* Heat Flow Down | R-3.0* Heat Flow Up

Reflectix® Insulation products are a technologically advanced Insulation material ideal for new construction or retrofit applications in commercial, industrial, metal and post/frame buildings. Our products are recognized for their thermal performance, easy installation, versatility, price and environmental friendliness.

Recommended Products:
Single Reflective Insulation
Reflective/Bubble/Bubble/White - Roll
• RDBW48100 (48” x 100’)

• 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:
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 or call 800-879-3645.

Air Space Requirements:
Installation Instructions:
Download Post Frame - Roof - Retrofit - Bottom of Truss Installation Instructions 0910.pdf
• The Reflectix® Insulation is installed with the “white side” towards the interior of the building.
• Pre-installation inspection - Check the roof area for clutter, water sprinklers, conduit and lights. Sprinkler systems are especially important. All water pipes must be below the Reflectix® Reflective/Bubble/Bubble/White Insulation to prevent the possibility of freezing in the winter.
• Nail 1”x 2” furring strips on the bottom of and perpendicular to the trusses on 22” centers. (Note: When truss spacing is 24” it is recommended to install the Reflectix® Reflective/Bubble/Bubble/White 48” product directly to the bottom cord of the truss.)
• Butt the furring strips together and tape. Staple tape for reinforcement.
• Staple the edges of the Reflectix® to the furring strip with 5/16" staples at approximately 4" intervals. Run subsequent courses of the product with a 3/4” overlap at the seams.
• Tape the seams with a Reflectix® White Poly Tape (goal is an air-tight, snug seam seal).
• Tape any butt seams with Reflectix® White Poly Tape, insure taped seam has a good full continuous bond.
• Staple product down the middle of the sheet into the furring strip above.

* Includes thermal resistance of 0.61 UP and 0.92 DOWN for interior air film.

Calculation Disclaimer:
All values are calculated based on the “ASHRAE Handbook of Fundamentals” heat flow up and down.


Additional Resources:
F2 - Solutions for the Pro (Revised 0416)
Zip Code Zone Locator
This function provides regional installation recommendations for the following applications: Attic & Cathedral Ceiling
DIY Product Calculator Type:
Roof/Attic Application: Radiant Barrier Locate a Retailer
0 sq. ft. of roof/attic area 0 rolls
*Note: This calculator is for the convenience of our customers. These recommendations are for approximate product quantity.

Video Library:

For additional videos, click here.
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