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DOW Thermax Foil Finish Insulating Sheathing choose thickness

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Please call to schedule pick up or delivery: 1-888-223-3050
DOW 00268429
Please call to schedule pick up or delivery: 1-888-223-3050

Product Description

 DOW Thermax Foil Finish Insulating Sheathing

THERMAX™ Sheathing is a nonstructural,rigid board insulation consisting of a glass-fiber-infused polyisocyanurate foam core laminated between 1.0 mil smooth, reflective aluminum facers on both sides. The glass-fiber reinforcement contributes to improved fire performance and dimensional stability. THERMAX™ Sheathing can be installed exposed to the interior without a thermal barrier.  THERMAX™ Sheathing offers high, long-term R-value. Used in conjunction with the appropriate joint closure system for the application, THERMAX™ Sheathing with its low perm rating helps to reduce moisture condensation within and behind the insulation.

We also stock foil tape for joining seams and providing a finished look. To view this product click here.

THERMAX™ Sheathing is specially designed to have a Class A fire rating and can be used in a range of concealed and exposed applications, above and below grade, and can be used in exterior walls. Because of its improved fire performance, THERMAX™ Sheathing is especially appropriate for hourly rated assemblies.
THERMAX™ Sheathing is approved for use, per Section 2603.5 of the International Building Code, in Exterior Walls of Types I,II,III and IV construction. THERMAX™ Sheathing is designed for use as
continuous insulation in both interior and exterior applications to assist in meeting and exceeding both the
most current IECC and the ASHRAE 90.1 energy standards. Maximum length is 30 ft. (9.1 m) and maximum
thickness is 4.25" (108 mm).

The foam boards are light but very large and are most approriate for local pickup or for ordering full pallets to your job site. 

This Thermax Sheathing is available with foil finish. Use along with Dow Wall and Floor adhesive or Dow Enerfoam to adhere panels to concrete walls and to fill any voids between adjoining panels.  Thermax is a closed cell foam product and is an outstanding moisture barrier.

Above you can choose between the following sizes:

1) 4 x 8 ft sheet 1/2 inch thick foil finish R value 3.3

2) 4 x 8 ft sheet 1 inch thick foil finish R value 6.5

3) 4 x 8 ft sheet 2 inch thick foil finish R value 13

Please call us at 888-223-3050 for additional information and bulk pricing discounts.

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Product Reviews

  1. Thermax Sheathing and White finish

    Posted by Albert on 21st Nov 2013

    I bought 2 types of Thermax insulation: White Finish board and Thermax Sheathing (aluminum face).
    To my surprise, they are of pretty different quality. White Finish is much better quality, pretty much finished face board and essentially heavier. I would certainly rate them 5+ stars and highly recommend.
    Aluminum face board are pretty low quality. Foiled face is very delicate and could be easily damaged even by touch of finger. I would give it 2 stars maximum and do not recommend.
    Special thank to AWAREHOUSE for delivery. Everything was delivered in great shape with no even minor damage to any boards which was not easy task for sure taking into account delicate nature of insulation.

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