SMART Timberframes | Enclosure Systems: Roof

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Enlosure Systems: Roof

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Since roof insulation is one of the most important components of a high performance timberframe home, we put a lot of emphasis on that aspect of the enclose system.

The most popular and efficient method of insulating a timberframe roof is through the use of foam panels. When selecting foam panels, you have 2 options: Polyurethane panels and Expanded Polystyrene panels. The main differences between both panels are as follows.

Expanded Polystyrene Panels:	- R Value of 3.5 - 4.0 per inch - Moisture resistant - Competitively priced alternative to conventional insulating methods while offering superior R Values
Polyurethane Panels:	- R Value of 3.5 - 4.0 per inch - R Value of 7.0 - 7.5 per inch, highest rated insulation per square inch available on the market - Better moisture and adhesive resistance - Better fire resistance - Most expensive option

At SMART Timberframes, we've developed a method of insulating timberframe roofs that is energy efficient and more cost effective than prefabricated panels. Our roof system is comprised of 4 elements:

1. 2" X 6" Tongue and groove pine decking is fastened directly to your rafters or purlins.This creates a base for the foam sheets to rest on and a beautiful finished ceiling. The decking is sprayed with a non-toxic, water based coating to protect it from moisture.

2. When the decking is in place, we apply a product from GRACE Construction Products called Ice and Water shield, which is the most efficient vapor barrier available on the market. This product offers superior protection against leakage.

3. Once a perimeter box is constructed and attached to the pine decking, we apply foam panels to the roof. You have the option to use Polyurethane foam or EPS foam. Your budget and preference will dictate the best option for your project. You also have the option to select foam panels varying from 5 1/2" - 9 1/2" in thickness (R Value of 28-40). Once all of the foam sheets are in place all the seams are filled with construction grade expansion foam to ensure that we have an optimal seal.

4. The last step is the application of 2"x4" strapping over the foam. This not only secures the foam firmly to the timberframe but it also enables the roof to breath and provides a solid assembly for the roofing material (metal or shingles).