Insulation Between Osb And Siding

3 benefits of rigid foam sheathing.

Insulation between osb and siding.

Plywood has an r value of 1 25 and fiberglass batts have an r value of 3 14. In addition to providing high performance and continuous insulation it helps to increase the structural rigidity of the building. How to install rigid foam under siding. And a material cost of 100 for 500sq ft for a total of 590 professionally installed or 100 for a diy installation.

It can be installed at a rate of roughly 75sq ft. This graph helps explain why. Installing foam board insulation under vinyl siding today more than ever before homes are being built with foam board insulation installed on the outside of the sheathing and under the siding. An hour by a skilled contractor for an installation cost of roughly 490 for 500sq ft.

Oriented strand board cost osb costs roughly 6 a sheet of 4 x 8 sheathing. By adding a layer of contoured foam insulation that completely fills the gap between the siding and the wall the impact of the panel significantly improved. Plywood passes moisture better than osb redistributes moisture better than osb and dries much faster when it gets wet. Isobrace osb combines the insulation performance of an expanded polystyrene panel with the rigidity of a 7 16 oriented strand board osb.

Hot sun can overheat wood siding causing it to dry excessively and crack. More effective insulation with r values ranging from 3 6 to 8 0 rigid foam sheathing has much better insulation per inch than other materials i e. Wood siding needs an air space between its backside and the face of foam sheathing. Notice the difference between the wet cup and dry cup tests.

And the huge difference at the end of the scale when things are really wet. This detail is used with both new construction and also with renovation work. Foam is less permeable to water vapor and the back of the siding stays wet as the face of the siding dries. As a result the siding cups cracks and sheds paint.