Insulating Under Bay Window Forum

I have removed the plasterboard and there is a 75mm airspace then roofing felt and the back of the external render.

Insulating under bay window forum.

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. Celotex pl4050 is a thermal insulated plaster board. Most people only insulate under the bay window. Buy this item from amazon uk.

I have a bay window in my kitchen facing south that gets very cold on the floor during the winter months. 50 mm celotex bonded to plaster board. New construction bay window floor overhang insulation detail. The sketch above shows one method for insulating the deck overhang at a bay window or cantilever that encloses a bump out.

5 replies 7 4k views dander forumite. In process of renovating and trying to do some of the work myself. Quite often the insulation in this area is dealt with long after the framing is finished and results in a very cold drafty spot in the house. Side walls also need insulating if no cavity exists.

I have only just found this forum so have already done quite a bit but want to check i have done it right before i finish the job. My first post here. Outside under the bay is open. The plaster was loose underneath the bay window in my 1940s semi.

I would like the underside of the bay to look nice. The area in the basement is finished but i can access the subfloor from inside the basement and i also am able to remove the soffit from the outside. No vapour barrier is required and the foam blocks a considerable amount of sound transmission from the outdoors too. Found that my bay window is completely uninsulated so want to get this sorted whilst i have all the plaster off.

So was thinking to use foam board to insulate the bottom but no idea what to use to clad it with. Either way filling the floor cavity with spray foam delivers excellent thermal insulation while also keeping drafts out of your bay window area. To be used under bay window. Basically the bottom of the bay window is un insulated and is causing condensation to form on the wood as its warm inside and cold outside.

So once i d ripped out the lath and plaster i wanted to the opportunity to insulate the bay before it is replastered. 6 march 2010 at 9 35am edited 30 november 1 at 1 00am in in my home includes diy moneysaving. So it would be great to get some advice on how to do this. Always remember anyone can post on the mse forums so it can be very different from our opinion.

Insulating cantilever floor in a bump out bay window i bay window bump out with a 2 foot exterior cantilever subfloor extending over the basement foundation wall.