Garage conversion floor level

Morning all,

I'm considering a garage conversion, but there's only about 3-4 inches between the concrete garage floor and the adjoining house and i'd like them to be at the same level post-conversion.

What are my options? Am I right in thinking that a wooden floor is out of the question because there'll be no room for ventilation? If I get a screed laid to this depth, then there'll be no room for insulation (whether required by building control or not, I'd like to include this).

So am I going to have to dig up the existing concrete floor? It will probably be tiled - does this make a difference? Also, where should the damp proof membrane go?

Cheers,

Nick

Staffs BCO's accept that it not always practical to hammer up the existing floor and will ask for a minimum of insulation or not bother ar all.

It does mean that the insulation loss via the floor means robustly insulating elsewhere i.e. the walls and roof/loft etc.

It is possible to 'float' a floor whereby you fit foam board insulation direct to the slab with t&g chipboard or ply laid on top.

Our living room used to be a garage, and it has a suspended wooden floor over the old concrete floor.

Thanks for the replies guys.

Gissle: Yep - suspended floors are fairly common for converted garages as I understand it, but usually there is more of a height differential between the garage slab and the main house which would permit a ventilation gap.

Noseall: I had someone round to quote and he suggested exactly that - thin layer of foam with chipboard or ply directly on top. I just wanted to check whether this would likely be ok or not. He seemed to know his stuff, but it never hurts to get a second opinion!

I must admit that I would like to put a decent amount of insulation under the floor as I can't stand it being cold under foot. But given that the missus wants it tiled, I'm thinking it's not worth digging up the slab.

4" = 1 inch of insulation + 3" of screed, on top of which you can tile.