Tiling from old floor to new floor

davlor

Hi - I am in the process of extending my kitchen by means of a new build. I aim to tile the entire area myself. Somebody mentioned to me that when doing this you need to tile on to a thin sheet of plywood in case the level of the floor in the new build drops when settling, hence causing the tiles to crack. Is there any truth in this?, or is there anything to worry about? Thanks for your comments.

Joey the lips

Tbh my experience is there is always settleing. I would actually suggest you consider lino for the first year however i am sure this is not in your thoughts.

The reaon you use ply is it acts as a floating floor and provided the whole settlement is only slight it should not crack however I always find it cracks along the join of the old and new. I would suggest you use an expansion bar here.This does not apeal to most which is why I suggest lino the first year.

davlor

Thanks Joey. You are right in that Lino wasnt exactly what i was thinking about....

My issue with the ply, is that the tile is quite thick, probably 15mm, so that on top of ply will lbring my floor level higher than i wanted !!!

I was thinking that i could start the tile "strategically" at the point between old and new, then if there is a shift, it may only affect the grout, not the tile.

Joey the lips

davlor wrote: »

Thanks Joey. You are right in that Lino wasnt exactly what i was thinking about....

My issue with the ply, is that the tile is quite thick, probably 15mm, so that on top of ply will lbring my floor level higher than i wanted !!!

I was thinking that i could start the tile "strategically" at the point between old and new, then if there is a shift, it may only affect the grout, not the tile.

Or else you could buy a couple of extra boxes of tiles and if they crack you will have replacements. They can be stored under the kickboards out of harm.

items

davlor wrote: »

Hi - I am in the process of extending my kitchen by means of a new build. I aim to tile the entire area myself. Somebody mentioned to me that when doing this you need to tile on to a thin sheet of plywood in case the level of the floor in the new build drops when settling, hence causing the tiles to crack. Is there any truth in this?, or is there anything to worry about? Thanks for your comments.

If floor is not solid, ie poured concrete then marine ply is used. The idea behind marine ply is to stiffen up a sheathed / boarded floor, sheaths of marine ply are laid in opposite direction of boarded floor then fixed every 3" minimum with screws. This will stiffen up floor reducing chances of movement / tiles cracking, flexible adhesive should be used when laying tile. Marine ply comes in different thickness, 6mm and 3mm is mostly used, 6mm for large area rooms like kitchens etc, 3mm for bathrooms / ensuites.

If you've got a solid floor then all you have to do is pour out some self leveling compound before tiling, when set tile straight onto floor using standard adhesive or flexi.

Either is a safe bet, success depends on person laying tile so if you've any doubts pay a tiler especially if you've a sheeted / boarded floor.

If your only building extension no reason why you cant be facilitated in a way to allow use of ply, all you have to do is - thickness of ply off finished sub floor / board level. If your pouring floors then you've nothing to worry about.

GreeBo

I think if your new floor sinks then cracked tiles/grout are the least of your worries

I'd give the new slab plenty of time to settle and dry out and then level the entire area with some self leveling mix.

WBP isnt going to stop a concrete slab from moving at all, but it does help to level out the movement on a wooden sub floor (but I always use 9mm as 3mm or 6mm is too flexible IMO and defeats the point)

+1 on buying extra boxes of tiles.

Joey the lips

Ment to say as above Powdered flex adhesive all the way. One that is polymer based. Larsen do a brilliant one in an Orange bag with a blue stripe.