Tilling on floor boards

spindizzy

Hi,

My kitchen has a old suspended timber floor. Is it possible to lay tiles on top. I'd imagine the floor would have a bit of give that might crack the gritting in time. Would the tile adhesive stick to the wooden floor? Is it possible to do and should I make any allowances or do anything before I lay the tiles

Outkast_IRE

most people lay plywood down and screw that down it provides a more solid surface. If it was me and i wanted to be safe i would prob use 3/4 inch ply. you might get away with 1/2 inch though depends on how the floor is

Buford T Justice

Outkast_IRE wrote: »

most people lay plywood down and screw that down it provides a more solid surface. If it was me and i wanted to be safe i would prob use 3/4 inch ply. you might get away with 1/2 inch though depends on how the floor is

You'd want 18mm at least to be on the safe side. Its only for a kitchen, so you don't need marine ply, so it wouldn't be overly expensive to do.

OP, is there much of a bounce in the floor currently?

major deegan

Yeah,there's also a flexible tile adhesive for use in timber subfloor situations.

spindizzy

Fingers McGee wrote: »

OP, is there much of a bounce in the floor currently?

Floor is fairly solid, little or no bounce.

There are 2 doors opening into the room and if i use ply I will need to trim a little of each, also there will then be a little step into the room at each door. Whats the best way to deal with this/may it look good

Buford T Justice

spindizzy wrote: »

Floor is fairly solid, little or no bounce.

There are 2 doors opening into the room and if i use ply I will need to trim a little of each, also there will then be a little step into the room at each door. Whats the best way to deal with this/may it look good

Perhaps rip up the floor thats there and replace the floorboards with the ply. This will reduce the amount you are raising the floor by. You will need to make sure that its screwed down every 2 - 3 inches to be as solid as possible.

That or cut the doors as you say, but there's not much yo can do about the dip that would be there afterwards though.

Sparkpea

a well screwed down (not nailed) 6mm plywood floor is ample thickness. make sure the tiles are laid with flexible tile adhesive for timber floors, like bal 2 part fast flex, or pro fix

Edit: I mean putting 6mm down ontop of t&g wooden floor

pms7

I have done this in a bathroom, can't remember what thickness ply used. Screwed every 6 inches. Still fine after 8 years.

North West

Hi Spindizzy

Make sure the floor boards are secure. Screw 12mm WPB to floor boards leaving a slight gap at joints. Use plenty of screws. You can then tile away. I use 12mm because 18mm brought the floor to high in comparison to other adjoining floors.
North West

Buford T Justice

North West wrote: »

Hi Spindizzy

Make sure the floor boards are secure. Screw 12mm WPB to floor boards leaving a slight gap at joints. Use plenty of screws. You can then tile away. I use 12mm because 18mm brought the floor to high in comparison to other adjoining floors.
North West

True. But T&G will be around 18mm or thereabouts anyway. Ripping this up and replacing it with WBP of the same dimension will have less of an impact on the height that the floor gets raised in the end result.

spindizzy

Just wondering why is it necessary to put down the ply, what's the reason. What does it do that the floor boards cant?

Buford T Justice

spindizzy wrote: »

Just wondering why is it necessary to put down the ply, what's the reason. What does it do that the floor boards cant?

You will have movement between each individual board that is linked to the other, this will also be the case for the natural expansion between the boards.
The idea of the ply is that its a single sheet so to speak, and if its screwed down well, there will be little to no movement on the floor.

If you tile directly down over the boards, you run the risk of the tiles either cracking or coming loose.

PS, Flex adhesive and grout is a must.

North West

Hi spindizzy

Floor boards alone will contract and expand. Waterproof ply ( WBP) will have minimal movement. Like fingers has pointed out with the movement in boards alone could crack, loosen tiles.

North West

Joey the lips

Seen as we are all contributing...

18mm ply...marine ply is really no harm..

Screw the ply down with brass screws `(screw to be the thickness of the ply and what ever the thickness of the floor is...no worry of clipping cables....

Screw the ply every 50mm/2" yes thats a lot of screws but its worth it..

Prime the ply....

Buford T Justice

If it was a bathroom, I would say that Marine is a must, but if its a kitchen then WBP would be a safe enough bet, but definitely go with the PVA primer.

Not arguing here, just my own opinion since Marine is ridiculously expensive and if its not essential, if you get my gist........

Sparkpea

when u boys says 18mm are u talking about removing the current floor or putting that ontop of? I say 6mm because its ontop of the standard t&g floor..

Buford T Justice

Sparkpea wrote: »

when u boys says 18mm are u talking about removing the current floor or putting that ontop of? I say 6mm because its ontop of the standard t&g floor..

Removing the current and putting this down instead, well my opinion anyway. T&G would be around 18mm, and you would add another 6 to that before you get to the tiles & adhesive. If raising the height of the floor was a concern then this way would reduce the amount of height gained.

Though 6 would be fine on top of the T&G

Joey the lips

Sparkpea wrote: »

when u boys says 18mm are u talking about removing the current floor or putting that ontop of? I say 6mm because its ontop of the standard t&g floor..

Nope... 18mm on top of a standard floor is what i done but depending on the floor and the toilet position i would use 6mm sometimes.

For example... if the toilet went out through the back wall 18mm would be an awful height to come up.

Having said that if your using a heavy time all the support you can give it in board thickness will help the adhesive..

Buford T Justice

Joey the lips wrote: »

Nope... 18mm on top of a standard floor is what i done but depending on the floor and the toilet position i would use 6mm sometimes.

For example... if the toilet went out through the back wall 18mm would be an awful height to come up.

Having said that if your using a heavy time all the support you can give it in board thickness will help the adhesive..

Its for a kitchen, which is why I suggested the WBP instead of the Marine. I would also have thought that 18mm is thick enough, but just my opinion