Fine Home Building Insulating Knee Walls Roof

In tight attics or odd shaped wall conditions i e.

Fine home building insulating knee walls roof.

In finished attic rooms with or without dormer insulate 2a between the studs of knee walls 2b between the studs and rafters of exterior walls and roof 2c and ceilings with cold spaces above. 2d extend insulation into joist space to reduce air flows. Although kneewalls can help turn attics into living space they often present insulation challenges most builders install fiberglass batts between the studs and some type of blown insulation between the floor joists. An unvented assembly can perform well but it s important to get the details right to avoid sheathing rot.

Enough of each tie remained exposed to anchor the stone facing to the concrete wall. Rake walls it s easier to handle than plywood or thermo ply and still gives you an r 19 r121 assembly. Added bonus the floor of this knee wall leaked too so there is a line of foam just above the floor joist. Thick rigid foam insulation onto the metal ties.

There are several common types of rigid foam insulation each with different pros and cons. There are many ways to build an insulated sloped roof. We prefer cellulose but we use fiberglass sometimes too. Air permeable insulation such as fiberglass batts dense packed cellulose or blown in fiberglass can t be used alone for an unvented assembly since these types of insulation can allow moist indoor air to reach the cold roof sheathing leading to condensation or moisture accumulation.

Another alternative for knee walls conditions is to remove and reinstall the batt insulation to qii standards. Blown insulation in the knee wall and top attics. Few building materials have been embraced by so many builders as rigid foam insulation certainly there are builders who avoid it but rigid foam can be used everywhere from beneath a basement slab to the rooftop and that versatility gets it into a lot of residential projects. Then cover that same area with an r 8 fsk affixing it using cap nails.

We reduced the air leakage nearly 50 on this house in shaker heights without insulating the walls. Insulating the knee wall with rigid foam keeps stone and cement which are poor insulators from conducting cold and dampness into the greenhouse.