Combination floors

**spooner68** · 10-08-2011

Just been to see a combination floor (concrete/floorboards) and am in a bit of a quandary. The floorboards side has a distinct hump, supposedly treated woodworm and bit of movement. The concrete side is flattish but cannot be raised up as all the external and internal doors and skirts have been fitted. Clearance to the french doors is barely enough for the tiles and addy.

The builder (bless) has fitted a kitchen over both bits but decided to do nothing with the existing timber floor. His comment to the customer was that it'll just need "levelling with a bit of screed". Ha!

So here's the deal, the timber needs to come up and be replaced with ply to match the height of the concrete and the joists need to have extra timber to stop the movement. So far so good. But what to do as an overlay on the ply as the floor cannot come up very far at all. Ditra, or is there a mesh (think I saw it in TSJ a while back) that can be used? A movement joint will be bang in the middle of the floor which is a long oblong about 2m wide by 6m long.

The tiles are bought and are 30x30mm slate (rough and rubbish but there you go).

Did I mention that the kitchen has been fitted along with the American fridge?

**peteablard** · 11-08-2011

Will the movement joint fall directly above where the ply and concrete join?

**spooner68** · 11-08-2011

that would need to be the case I think.

**spooner68** · 13-08-2011

so anyway have any of you seen the mesh for laying straight onto ply/floorboards? Is it any good as the timber side cannot be over-plyed etc as the concrete side is too high. I had a look through ny back issues of TSJ and cant find the ad.

**Dave** · 13-08-2011

Plastic ply or G-mesh... both DIY gimmicks..

**kilty55** · 13-08-2011

i have some samples of g mesh,not used yet and no idea of what its like

**spooner68** · 13-08-2011

that was my worry. Any ideas? Could I use 18mm ply to replace the floorboards with 6mm backer board and then a 2mm slc to blend teh floors together and hope I can run the stone under the doors? I think its the only answer.

**Dave** · 13-08-2011

Originally Posted by spooner68

that was my worry. Any ideas? Could I use 18mm ply to replace the floorboards with 6mm backer board and then a 2mm slc to blend teh floors together and hope I can run the stone under the doors? I think its the only answer.

You could ye.. but joint at substrate break.