Insulating Cape Cod Attic Without Soffit

Suggestions for un vented or hard to vent building roof cavities.

Insulating cape cod attic without soffit.

One of the best methods is rigid foam board with sealed joints over insulation in the knee wall. Plenty of homes have soffits without soffit vents. Rather than having to spend days or weeks in a dirty attic carefully caulking every crack and filling all the holes with cans of foam and then carefully laying out insulation you can instead just remove the old insulation and have a foam contractor come in and in a day or less your attic will be completely air sealed and insulated. Because it s hard to insulate these areas many capes leak heat at the eaves a recipe for ice dams.

I suggest you use polyisocyanurate instead of blue styrofoam xps since polyiso is more environmentally benign. Two ways to insulate attic knee walls article doesn t mention what to do with the sides of the triangular area e g. Authoritative expert building diagnostic and repair advice toxic black mold and. In an attic without soffit vents you can add insulation in the corners and the wedges between the slope of the roof and the floor of the attic which serves as the ceiling for the room below.

The ideal solution especially if the rafters are not deep enough to allow for code minimum cavity insulation is to add rigid foam above the roof deck. An attic s intake vents are most commonly installed directly in the soffit either as individual vents spaced every few feet or as one continuous perforated soffit running the entire length of. One method mentions what to do with the sloped roof and the other method mentions what to do with the floor and knee wall. Roof eave venting on roofs with no overhang or soffit how to correct improper or inadequate attic or under roof ventilation in buildings detecting and correcting attic condensation and preventing ice dam leaks in buildings how to correct improper or inadequate attic or under roof ventilation in buildings.

How to avoid condensation leaks attic mold insulation mold structural damage to roof framing when roof venting is not possible cathedral roof and knee wall insulation venting air path options in older homes hot roof designs. This is not very easy in most of the older houses we work on because the hatches and attics are too small to get rigid foam board through. Instead of adding only 3 4 inch of rigid foam add 2 inches. Since you are asking how to insulate your house here s my advice.