Levelling where extension concrete floor meets existing timber floor

[jimtg_90]

We're having an extension built - knocking through the existing kitchen to make a kitchen diner and the builders will soon be laying the insulation and screeding. The existing kitchen floor is currently tiled.

Should I ask the builders to bring the screed level to the existing timber floor? (i.e. after removing the tiles + any subfloor that is under the tiles?

The problem I can see with this is that I will need to lay 6mm ply over the wooden floor area before laying the new floor but I assume I wouldn't do this over the concrete extension floor - so the existing kitchen floor level will then be 6mm higher than the extension.

The new floor wil either be LVT or ceramic tiles - haven't decided yet.

If I do as above - would I then need to use self levelling compound over the extension concrete floor to bring it up 6mm?

Alternatively should I lay the 6mm ply before they screed and ask them to bring the screed up to the level of the ply?

Thanks in advance

 

[foxhole]

6mm cement boards.

 

[jimtg_90]

Thanks @foxhole - I assume you mean lay the 6mm cement boards over both the concrete extension and the wooden floor? What sort of adhesive do you use to attach them to the concrete/screed?

 

[dazlight]

Alternatively should I lay the 6mm ply before they screed and ask them to bring the screed up to the level of the ply?

Thanks in advance[/QUOTE]

Yes do this. Then you can do a 5mm coat of a fibre smoothing compound over the lot ready for Lvt or ceramics

you will prob need a moisture suppressant on top of the new screed