Rated 4.8 out of 5Â by 4
Rated 5 out of 5Â by BvilleBound Excellent insulation solution for interior and exterior -- with some installation tips
We are working on a deep remodel of a home along the shore in Massachusetts. Built as a summer cottage in 1950, most of the walls had no insulation. To bring the home up to current code (required with a major remodel) and save money on heating and cooling, we used Owens Corning Formular to insulate the inside and outside. Here are a few tips:
> Inside: All of the walls were open to the studs. Due to the project schedule, spray foam and packed cellulose were not options. So we filled the stud bays with Formular board using the "cut and cobble" method. Large pieces are easy to form by scoring with a knife and breaking the sheet across a sharp edge; small pieces and shapes were cut with a serrated blade. We sealed the gaps and edges with Great Stuff foam. (An important step -- don't skip it!) To nearly fill the 2 x 4 stud bays, we used two layers: 2" and 1". A couple of photos are attached. Verdict: this takes more time than spray foam or packed cellulose, but is a great solution for remodels and do-it-yourself projects.
> Exterior: To eliminate the risk of condensation on the sheathing in winter, and boost insulation efficiency, we wrapped the entire house with 2" of Formular 250 board. New house wrap went on first, then the foam board. We used corrosion resistant Spax "washer head" screws to attach the foam board. The joints, gaps and holes were sealed with Great Stuff foam. (As noted above, this is an important step!) 1" x 3" pressure treated firring strips were added last (for the siding and trim) and attached to the sheathing with long corrosion resistant Deckmate screws. A photo is attached. Verdict: Formular foam board is a great exterior insulation and air-barrier solution for remodels and new construction, including walls and roofs. This thickness also blocks water vapor, to prevent rot.
Note: Windows and doors in a remodel will be installed against the sheathing, and need to be trimmed out with external "extension jambs" -- to compensate for the thickness of the foam board on the outside. This is easy and almost unnoticeable. We used Azek / Veranda PVC trim board, which never rots and never needs to be painted. (If your trim color is white!)
All of the products noted above are available at Home Depot.
The result: 2" of foam board outside and 3" inside, all sealed with Great Stuff to prevent air leaks. The layer on the outside also eliminated most of the "thermal bridging" between the framing and the outside air. (Wood is a surprisingly good conductor.) The total R value is roughly 25. We installed all of this during the winter, and immediately noticed a major impact on heating costs -- even though the roof has not been insulated yet!
I hope all of this detail is helpful!
June 13, 2014
Rated 5 out of 5Â by Terrie beautiful stuff good product
I used the 1 1/2 thickness between studs in basement and directly against the brick basement wall as is used in corningwares more elaborate basement lockin system which was out of my price league.. beautiful stuff.. easy to work with. basement is tight as a drum and warm with raised wood floor as well. I intend to use the stuff as mentioned in youtube video of Cleveland's Dr. energy saver to help upper floors be cooler as well. it's so hot up there, but I think it will be easier to work with and the job will go quickly with awesome results and family will sleep more comfortably.
July 1, 2013
Rated 4 out of 5 Very good product, R-Value
For anyone who is looking to buy this product, its R-Value is R5 per 1 inch of thickness. That is so far the best I have seen.
August 6, 2013
Rated 5 out of 5Â by Drucifer Great features and easy to install.
I feel this product is a must have for anybody. If your a Pro. or a d.i.y. weekender like me, this product will help you get the job done fast and easy. I've noticed a huge different in my cooling bill for my shop. light weight and easy to work with... clean up was a breeze.
May 19, 2012