Underfloor insulation - can I do this?

[b9jobber]

I've got a 1930s semi with groundfloor suspended wooden floors.

I've taken up the carpets to expose the tong n groove floorboards - downside is the boards are cold in winter.

Just a thought - could I inject cavity wall insulation under floorbards to keep out draughts? The cavity is about 18" deep to soil.

I don't fancy pulling up each board to insulate under them - it'll cost an arm and a leg to replace split/damaged boards.

What do you think?

[welsh brickie]

you could tack 3mm ply and tape the joints on the floor then relay the carpet.
It would cost a fortune to inject cavity wall insulation under the floor.And the gap under the joists is there for a reason it should be kept clear.

[b9jobber]

you could tack 3mm ply and tape the joints on the floor then relay the carpet.
It would cost a fortune to inject cavity wall insulation under the floor.And the gap under the joists is there for a reason it should be kept clear.

cheers mate, but we like the exposed boards. Spose will have to suffer the cold..........