Insulating Low Pitch Attic

Stage 2 of insulating a low slope roof.

Insulating low pitch attic.

There are lots of ways to insulate a low slope roof and most of them are wrong. Gaps in the framing need to be sealed any holes from electrical wiring must be filled and so on. Eric dymond lives in a 1920s baltimore row house that needs a new roof. To create a warm pitched roof insulation such as kingspan kooltherm k7 pitched roof board should be fitted between and over the rafters.

Currently the built up asphalt roof is installed over homasote or something similar and a roof deck made of wood planks. In warm climates zones 1 through 4 low density open cell spray foam insulation is the typical choice since it is vapor permeable and will allow drying of the exterior sheathing and roof framing if they happen to get wet via diffusion into the interior of the building. As this requires fitting insulation above the rafters the roof covering will have to be removed in order to fit the insulation. Insulate the walls carefully and effectively so that you don t wind up with further problems down the road.

In older buildings the usual method is to install fiberglass batts or cellulose on top of the leaky ceiling with a gap of a few inches or sometimes a few feet between the top of the insulation and the roof sheathing. Plan to pull up the flooring and layer new insulation on top of the old. Rigid board insulation is the most common type of insulation used in low slope commercial roofing. He plans on replacing the low slope built up roof with an epdm membrane and the question is how to insulate it correctly.

You want to keep condensation from forming anywhere in your attic. Because the simplest and cheapest way to insulate an attic is to add material to the floor. But if the floor is covered in plywood you can t stuff enough insulation beneath it to do the job sufficiently not even in warm climates. It is made from cellular plastic or fibrous materials and pressed into boards.