Attic conversion insulation oprions
I’ve inherited a project from a previous homeowner …. attic space to loft conversion. On both sides of the loft there is attic space. Keep in mind that the knee walls and loft ceiling were never finished. In place of an old gable vent a window was placed. There are no soffit vents or ridge vents. The house was built in the 50s and the insulation on the floor of the attic is batt. My questions concern how to insulate this new loft. I.e. the ceiling and knees walls. Is spray foam the way to go in the cathedral ceiling with no venting? Does this need to extend into the triangle space behind the knee walls? Is it possible to spray foam just the cathedral part in the loft and backside of the knee walls. If so what do I do with the triangle space in the absence of soffit and roof vents? Cut them in? I should also note that one side of the attic would be hard to reach if spray foaming it in becomes the only option.
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