Insulate Under Bay Window

Celotex pl4050 is a thermal insulated plaster board.

Insulate under bay window.

Most people only insulate under the bay window. No vapour barrier is required and the foam blocks a considerable amount of sound transmission from the outdoors too. Side walls also need insulating if no cavity exists. I want to insulate outside under the bay but fiberglass insulation is too thick as i only have 1 1 2 between the bay ceiling to the bottom of the siding.

The rim joist under the window appears to have only the 1 8 green foam vinyl and lap siding covering it no other insulation. Buy this item from amazon uk. Bay window and floor deck cantilever insulation details. I recently found the styrofoam under the bay was only press fit in some areas no fasteners held up by a friction fit on the back side of the lap siding.

This high performance thermal insulation board has 50mm of pir insulation. Bay windows are one of the more complicated window styles to install but their impact is well worth the effort. I have a bay window in my kitchen facing south that gets very cold on the floor during the winter months. In this article i ll share a detail for new construction and also a detail for renovating existing bay window.

50 mm celotex bonded to plaster board. To be used under bay window. I ve written quite a few articles on how to insulate basement walls and floors but one more specific topic related to this subject keeps coming up and that s how to insulate a bay window floor or cantilever floor framing. Either way filling the floor cavity with spray foam delivers excellent thermal insulation while also keeping drafts out of your bay window area.

And the farther a bay window protrudes from the house the more dramatic the effect and the more it opens a room. Outside under the bay is open.