Flooring Question

bugbyte_2

Hi,
I wonder if there is someone who can answer this question - I'm having an extension built and as part of the plans I am having the existing kitchen tiled. The existing floor is floorboards over joists. The floor has a slight spring to it but nothing unusual. Our tiler has said that he will use 6mm board under the tiles.

Is this thick enough or is he scrimping?

Thanks in advance,

Bugbyte.

dinofabio

I have used 6mm ply in the past but most tilers will tell you 12mm min or even 18mm.

The problem is that you don't want to raise the floor level too much.

eg

12mm ply
tile thickness 10mm
adhesive 5mm

floor level has been raised by over an inch.


Personally, I would go for at least 9mm ply.

Start by screwing down all existing boards to the joists.

overboard with min 9mm ply. min of a screw every 150 mm.

This should create a stable enough floor to tile on.

Use quality flex grout and adhesives eg Bal

Like I say, go for a min 9mm ply, but use a thicker ply if you can get away with it

dinofabio

Remember, if you floor has movement, your tiles will have to come up! and you'll end up doing it again

bugbyte_2

Thanks for the reply - I will ask my project manager about it tomorrow. I agree - at least 9mm as I don't want to do this again!

dinofabio

If you are worried about the floor levels, I have found using an extra wide strip between rooms solves the problem (lessens the angle)

dinofabio

meant to say if any of your existing floor boards stick up (standing 'proud' of the others) after screwing down, use an electric plane to level off as best as you can - you don't want to create a void underneath as that can cause movement when you walk on it.

27col

It might be more to the point if the floor was fixed so that it did not "spring". Until this is done anything else is likely to be a bit of a lash-up.