Post Frame Building - Product: Reflective One Side
Post Frame Building - Roof - New

Below the Purlins
Open Interior
R-6.4* Heat Flow Down | R-3.7* Heat Flow Up

Above the Purlins

Open Interior
R-3.8* Heat Flow Down | R-3.5* 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 and price.

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: (There are 2 options)
Download Post Frame - Roof - New Installation Instructions 0910.pdf
1. Metal Roof with Product Below Purlin

• The Reflectix® Insulation is installed with the “white side” towards the interior of the building.
• After the trusses are set, run two purlins to make sure the trusses stay true.
• Attach the Reflectix® Reflective/Bubble/Bubble/White product to the first truss with at least 5/16” staples. Temporarily nail a 2”x 4” block over the end of the product to prevent it from pulling away.
• Roll out the product across the top of the trusses, pull tight and staple.
• Run subsequent courses of the product with a 3/4” overlap at the seams.
• Tape the seams with a Reflectix® Foil Tape (goal is an air-tight, snug seam seal).
• Install purlins over the insulation. Nail or screw to the trusses through the product.
• Install the metal roof to the purlins.

2. Metal Roof with Product Above Purlin (see illustration above)
• Per instructions above except install Reflectix® Reflective/Bubble/Bubble/White Insulation after installing the purlins.
• When installing product, insure that a minimum of a 3/4” drape (middle of cavity) is present.

* 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.

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