Bottom of the Purlins
R-6.4* Heat Flow Down | R-3.7* Heat Flow Up
Note: Installation instructions and illustrated drawings are recommendations only, while proper local construction methods are the responsibility of the installer.
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.
Single Reflective Insulation
- 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
Installation Instruction pdf: PFB2 Roof Retro – Btm of Purlins Revised 04023
- The Reflectix® Insulation is installed with the “white side” towards the interior of the building.
- Inspect the roof area for clutter in buildings where there is no ceiling.
- Measure the distance between the trusses. Many times, the distance will be 4’ or less. In some geographical areas, due to snow load, the distance will be as close as 2’.
- Cut pieces of the Reflectix® Reflective/Bubble/Bubble/White Insulation 6” longer than the distance between the ridge pole and the bird’s mouth.
- Staple the product to the bottom of the purlins with 5/16” staples, 3” to 4” apart. Turn the edges down and staple to the side of the top cord of the trusses.
- Staple the top of the insulation to the ridge pole and the bottom to the top plate at the wall.
- Tape any butt seams with Reflectix® White Poly Tape. Make sure the tape is applied so that a proper bond occurs.
* 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.
Review These Important Safety Guidelines Prior to Installation:
- ALWAYS check local building codes before installing Reflectix®.
- ALWAYS check the area you are insulating and make any needed repairs. Any worn wiring should be replaced before you begin installing Reflectix®.
- ALWAYS make sure work areas are well ventilated and well lighted.
- ALWAYS use eye protection when operating a staple gun.
- ALWAYS use caution and common sense when using a staple gun. Be aware of electrical wiring locations. Stapling into a wire can cause severe shock or death. NEVER staple into electrical wiring.
- ALWAYS be careful when working with large pieces of Reflectix® on windy days.
- When installing Reflectix® on bright sunny days, it is best to wear sun glasses.
- Do not work in areas such as attics when temperatures are too hot.
- Please Note: The intention of these Installation Instructions and 3-D renderings are for the sole purpose of illustrating the correct location and relative position of the Reflectix® products in specific building assemblies. The correct construction methods and techniques are the responsibility of the installer or contractor. The methods outlined are recommendations on location of the Reflectix® products as a guideline. There are no claims on the part of Reflectix, Inc. that these building assemblies are finite standards or meet building code requirements (as they can vary by region).
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 the “Additional Resources” tab. The documents are also available by e-mail at firstname.lastname@example.org or call (800) 879-3645.
Pictured: 1. Single Reflective Insulation