Installing oak flooring over uneven tiled floor

[kevingill]

I am trying to work out the best way to install T&G solid oak flooring over an uneven kitchen floor.

The kitchen was extended by the previous occupants. The original part is flat and level (6ftx5ft), the newer part (10ftx6ft) slopes off (but is flat) from where it meets the old part. The drop is about 2 inches over 10ft. I tiled over this about 6 years ago and have smoothed out the ridge somewhat, but the transition from level to slope still remains. I will be installing the new flooring so that it runs lengthways with the ridge so the joints will take some of the curve.

The guy in the "orange" floorshop recommended laying down 6mm ply first to try and smooth out the ridge, but I would like second opinion on this matter. Also, should I glue down the ply to the tiles or screw? In addition, do I need any damp-proof membrane?

 

[WoodYouLike]

Depedning on what type of floor you are installing, solid boards and standard wood-engineered boards can 'handle' a sloop of 2mm per meter. Don't expect this from thin wood-veneer or melamine laminate.

Installing plywood is a good alternative, but screw it down, the adhesive will have problems bonding properly with the tiles.

 

[kevingill]

Thanks for replying.

The flooring is solid oak at 18mm thickness, i.e. it's not the engineered stuff.
In particular, there is a chamfer on each edge - I thought this might help to hide any gap that might appear as the flooring covers the hump/sloop.

I will screw down some 6mm ply first - I guess a damp-proof membrane is not required underneath the ply?
Should I then install as a floating floor with thin foam unerlay on top of the ply? (I don't want the new floor to be too thick).