Rigid Foam Sheathing Siding

Rigid foam sheathing can cause moisture to accumulate on the back of siding and cause staining buckling and damage to finish coats.

Rigid foam sheathing siding.

Insulated foam sheets are also used as an insulated sheathing underlayment for exterior siding. Many houses built today have a double wall type of insulation with fiberglass batts fastened between the studs on the inside and rigid foam board over the wall sheathing on the outside. This eliminates thermal bridging which is the energy lost through wall studs. 2 in x 4 ft x 8 ft 1 faced polystyrene garage door foam board insulation item 15357 model 2x48x96 r tech.

Current pneumatic nailers have maximum fastener lengths of 3 to 3 5 which limits insulation thicknesses to 1 5 max 3 5 fastener to siding 1 embedment 3 5 0 5 1 5 1 5 max insulation therefore for insulation greater than 1 5 direct. Moisture can get trapped between the siding and the foam leading to paint failure and causing clapboards to cup and curl. Thick narrow siding. Sheathing and penetrate framing a minimum 1 inches.

Install rigid foam over or in place of plywood osb or other wall sheathing. Use thicker siding patterns in widths of 8 203 mm or less. 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. Install continuous rigid foam insulation or insulated siding to help reduce thermal bridging through wood or metal framed exterior walls.

The cavity is stuffed with fiberglass then expanded foam sheathing followed by cedar board and batten siding. 3 benefits of rigid foam sheathing. But if you use wood clapboard siding foam sheathing can cause trouble. The following recommendations are meant to minimize potential problems when cedar sidings are applied over rigid foam sheathing.

Our house is 2x6 construction built in 1984 near milwaukee wi. Rigid foam across foundation also.