Post Frame Building - Product: Reflective Both Sides
Post Frame Building - Roof - New

Below the Purlins
Metal Interior
R-11 Heat Flow Down (and a Radiant Barrier) | R-5.1 Heat Flow Up
Open Interior
R-9.0* Heat Flow Down (and a Radiant Barrier) | R-4.4* Heat Flow Up

Above the Purlins

Metal Interior
R-6.8 Heat Flow Down (and a Radiant Barrier) | R-6.0 Heat Flow Up
Open Interior
R-6.4* Heat Flow Down (and a Radiant Barrier) | R-4.3* Heat Flow Up
Please Note: In addition to the stated R-value, this application also provides a Radiant Barrier. As a result, a 94% + reduction of the radiant energy that ordinarily would be transmitted to the interior of the building is blocked.

Reflectix® 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 Reflectix®. Our products are recognized for their thermal performance, easy installation, versatility and price.

Recommended Products:

Double Reflective Insulation
Staple Tab, Reflective/Bubble/Bubble/Reflective - Roll
• ST48100 (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 (first illustration)

• After the trusses are set, run two purlins to make sure the trusses stay true.
• Attach the Reflectix® Reflective/Bubble/Bubble/Reflective, Staple Tab 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 at approximately 4" intervals.
• Run subsequent courses of the product with the 3/4” staple tabs overlapping 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 (second illustration)
• Per instructions above except install Reflectix® 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 1.32 UP and 4.55 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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