DIY Home Improvement Forum banner

Suspended floor insulation

832 Views 7 Replies 2 Participants Last post by  Windows on Wash
We're going to be renovating our 1930s house. As part of this I would like to insulate the floor. It is a suspended timber floor, with the floor about 40cms above the ground.

We can't use spray foam insulation as the gap is too small.

What suggestions for floor insulation that won't raise the floor much or cost the earth?

Sent from my ONE A2003 using Tapatalk
1 - 8 of 8 Posts
Is the floor covered with a vapor barrier? Where is the home?
The house is in South West London. No vapour barrier yes, all there is at the moment is an underlay and a carpet, but as part of the renovation we will replace the carpet with an engineered floor.

Sent from my ONE A2003 using Tapatalk
I am confused. Is there a dirt floor directly beneath the framing or is this floor over a basement or crawl?
Yes, there is dirt floor below the joists. Quite surprising, but this is common for houses in the area!

Sent from my ONE A2003 using Tapatalk
No idea on moisture. The surveyor's report concluded there weren't enough air bricks, but we've not had any issues with damp. The ground is very clay like and totally waterlogged in winter.

Unfortunately because the space is too small to allow safe access we can't use spray foam insulation.

Sent from my ONE A2003 using Tapatalk
If you insulated the topside of the floor, you will make the joists colder and more likely to form condensation.

If the subfloor is going to be off, you can scab in some rigid foam and shoot it with spray foam if you want.
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.