help needed on porclin tiles

[terry the tiler]

hi ! ive got my first porclin floor job in around 3 weeks time, the tiles are 600 by 300 , is a bathroom floor in a victorian house , the bathroom is upstairs and i was wondering wot mm ply you thinks best ? it has chip board on which is in ok condition but could be taken up if needed. customer also wants a 2mm/3mm grout line ! was thnking of over boarding with 6mm ply but no sure? ive used that cement based water proof boards before instead of 6mm ply but found it was a nitemare to screw down , i hade to pre drill every hole and use a countersinker before screwing it down so dont fancy using that stuff again !! any advice ? also iam tiling up to the skirtings so would i need to leave a 5mm gap between skirting and tiles for expantion?

[smurf21]

6mm ply a definate no no use NO more Ply backer board its glued down with mega adhesive and screwed 8 screws per board using NMP self tapping screws


you use the backer board in place of 18mm ply

[Sir Ramic]

And dont put the screws too near the edges as it will crack the boards. No need to pre-drill but you can if you really want. Why not predrill all the boards at once by laying them on top of each other. The screws when used with No More Ply are not used for primary fastening but to act as a clamp when using their Polyurethene adhesive.

Oh and backer boards are not there to add strength, the existing floor needs to be strong enough before laying backer boards.

[diamondtiling]

If the chipboard floor is just "ok" why not take it up and use 18/22 mm boarding instead, this will give you a far superior start, no more ply boards should not give you those sort of problems, you stick and glue it down, bond the edges before you fix them, can you remove the skirts? if so you will get your cuts in much faster and give a better finish, re-fit the skirts and cork the tops and corners for a nice finish, if you cant do this then you will need to allow a gap, use flexible grout/adhesive, bond everywhere with acrylic bond, if the porcelain has rectified edges then a small grout line is better although there is a BS minimum spec, I should remember but cant, someone will say what it is

[terry the tiler]

6mm ply a definate no no use NO more Ply backer board its glued down with mega adhesive and screwed 8 screws per board using NMP self tapping screws


you use the backer board in place of 18mm ply

thanks ! so i guess no one uses 6mm ply anymore then ?
can i get the backer board in 6mm if i was to over board the chip board ?

[brian c]

yes 6mm cement board.

[terry the tiler]

If the chipboard floor is just "ok" why not take it up and use 18/22 mm boarding instead, this will give you a far superior start, no more ply boards should not give you those sort of problems, you stick and glue it down, bond the edges before you fix them, can you remove the skirts? if so you will get your cuts in much faster and give a better finish, re-fit the skirts and cork the tops and corners for a nice finish, if you cant do this then you will need to allow a gap, use flexible grout/adhesive, bond everywhere with acrylic bond, if the porcelain has rectified edges then a small grout line is better although there is a BS minimum spec, I should remember but cant, someone will say what it is

so if i took up the chip boad and replaced with say 22mm no more ply boards would it be the same strenth as the chip board i took up ? and would it handle 15mts of porclin ?

[terry the tiler]

do u think my rubi ts60 will cut the straight cuts on porclin?

[diamondtiling]

you cant get no more ply that thick terry, there would cost £1,000,000 per board matey

[diamondtiling]

I only use sigma terry, I couldn't answer that one for you friend but loads use rubi on here, you will have your answer in 10, 9, 8, 7, 6,........

[smurf21]

terry check it ou t

NoMorePly, The Ultimate Tile backer Board

[terry the tiler]

you cant get no more ply that thick terry, there would cost £1,000,000 per board matey

ha ha !! ive just been on there website and iam well impressed with no more ply ! it looks like its the one 4 me ! iam gona over board the chip board with no more ply 6mm !! carnt wait to get started ! i might ring the customer up now and ask him if i can do it tonight !! ha ha ! thanks for the info everyone

[stevee]

hey lads ,that no more ply does look good ,no 8x4 sheets, why would anyone bother with ply? please enlighten me in my quest for knowledge,steve

[365drills]

hey lads ,that no more ply does look good ,no 8x4 sheets, why would anyone bother with ply? please enlighten me in my quest for knowledge,steve

Take a look at this Job.



In the picture above you can see the builder laid down a sheet of 9mm ply onto the existing floor joists then tiled on top.

This particular builder is trying to make the most money from the job, to do it quickly and wants to move on. Doing it this way saves him money as well as time and petrol.

[brian c]

Richard that looks as if the ply is laid on the floor boards m8.If he laid 9mm ply on the joists then this would not be strong enough as you would have deflection issues.If you mean he has plyed out on top of the floor boards then yes that is fine so long as the boards are fixed solid and the ply screwed at 250mm intervals and primed according to manufacturers spec then thats fine...this is what i do.

[LM Ceramics]

as mentioned 6mm backer board or at least 12mm plywood but id go for the 6mm backer board would work out cheaper

[doug boardley]

thanks ! so i guess no one uses 6mm ply anymore then ?
can i get the backer board in 6mm if i was to over board the chip board ?

yes, hardiebacker 250, its dimensions are 1500 x 900 x 6mm, the way forward imo

[smurf21]

I dont know where you guys are getting your info from but a minimum of 15mm plywood is recommended for overboarding timber floors ,you cant get 15mm so the next best is 18mm( not 9mm or 12mm) or use a suitable tile backer board 6mm thick.

[terry the tiler]

just been to c that porclin floor job i was on about , i was informed by the customer it was chipboard under the lino and it was in ok condition, so i took the lino up and its floor boards not chipboard and there not level so iam woried that if i fix 6mm no more ply it will end up all uneven ? it would be ideal to over board it with 18mm marine ply but 18mm ply on top of floor boards plus the thickness of porclin looks about 15mm plus addy would b to much of a bulid up for door! any advice ?

[smurf21]

just make sure the floorboards are screwed down well and go with the NMP any slight unevenness you find after you will be able to take out in your addy bed