Floor rennovations

[daved2424]

I am currently taking my floor up in the living room and kitchen. I plan to fit Celotex between the joists. In the living room there is a hearth beneath where an old chimney used to be. In the kitchen there is a raised concrete area finished with tiles. Should these both be removed and joists put in if I am going to insulate to prevent thermal bridging and possible dampness, or will it be ok?

If that is fine, I am going to remove the tiles on top of the concrete slab, lay a membrane on top of the concrete, and then cover the whole floor with chipboard and tiles. Is this the right way to go about it?

Any help will be much appreciated.

 

[ree]

Lifting your floor is not a good idea. Plus there's no particular large benefits for insulation to be retrofitted between joists.

The other questions have been dealt with extensively in recent posts. Follow my back posts, for instance, or use the search facility.

 

[daved2424]

Why is it not a good idea?

There might not be many large benefits for fitting underfloor insulation in California, but there certainly is in London - the house is bloody freezing.

 

[dazlight]

What floor coving you putting down mate ?

 

[daved2424]

Tiles in kitchen, carpet elsewhere.

 

[geraldthehamster]

I am currently taking my floor up in the living room and kitchen. I plan to fit Celotex between the joists. In the living room there is a hearth beneath where an old chimney used to be. In the kitchen there is a raised concrete area finished with tiles. Should these both be removed and joists put in if I am going to insulate to prevent thermal bridging and possible dampness, or will it be ok?

If that is fine, I am going to remove the tiles on top of the concrete slab, lay a membrane on top of the concrete, and then cover the whole floor with chipboard and tiles. Is this the right way to go about it?

Any help will be much appreciated.

I took my ground floor up, as you are doing, and insulated with Celotex, and it makes an appreciable difference. Search the forum for "suspended floor insulation" for methods and opinions on the best way to do this.

I wouldn't worry about removing the existing concrete. When you say "cover with chipboard and tiles", I assume you mean chipboard in one place (where you are carpeting) and tiles in another? I wouldn't tile onto chipboard.

Cheers
Richard

 

[daved2424]

I assume you mean chipboard in one place (where you are carpeting) and tiles in another? I wouldn't tile onto chipboard.

Cheers
Richard

Thanks Richard, things are becoming a bit clearer now.

In the kitchen I have a mixture of floorboards and a concrete section (which I guess originally had the boiler, cooker and sink on) - see attached. If I put marine ply across both surfaces and tile on top of that, that should be ok? The concrete section might be a blessing as that is where most of the appliances are going including the washing machine...

Untitled

• daved2424
• 26 Feb 2015
• 1

 

[geraldthehamster]

Ply, securely fixed and at least 18mm, is an acceptable substrate for tiling.

Cheers
Richard

 

[daved2424]

Thanks Richard, really appreciated!

Just one more quick question... I should also put a membrane down beneath the ply and above the concrete, correct?

 

[geraldthehamster]

I should also put a membrane down beneath the ply and above the concrete, correct?

Wouldn't hurt. Where is the top of the concrete slab in relation to the top of the joists, and how are you intending to fix the ply to it?

Cheers
Richard

 

[daved2424]

There are quarry tiles on top of the slab and this is roughly flush to the boards. I was going to knock off the tiles and use a self-levelling compound to make it perfectly level between the two areas and then ply on top of that.

 

[geraldthehamster]

There are quarry tiles on top of the slab and this is roughly flush to the boards. I was going to knock off the tiles and use a self-levelling compound to make it perfectly level between the two areas and then ply on top of that.

That sounds reasonable. How big is the concrete slab?

Cheers
Richard

 

[daved2424]

If you look at it like an L-shape, on the long sides it is about 2/3 meters and about 0.7m deep.

 

[geraldthehamster]

If you look at it like an L-shape, on the long sides it is about 2/3 meters and about 0.7m deep.

If it's that large, I'd be inclined to screw and plug the plywood onto it, but I've not actually done that, so you'd be better taking advice from someone who has. Again, try searching the forum.

Cheers
Richard