My bathroom floor has been tiled (mosaics) with stirling board used as the sheeting. I have told my tiler it should be marine plywood and not the former because it is more resistant against any mositure.

What would you normally use?


Ta


Marc

Surely if the board has been primed with an acrylic agent it should be fine?

Neil

stirling board is water resistant unless its a wet room you've nothing to worry about stirling board will be ok

there is a new product on the market called NO MORE PLY i use this its 6mm thick moisture resistant easy to cut and transport works out about £10 per 1200x600 board best product i have used if you need more info on it just pm me

I normally use WBP plywood or marine ply of 9mm thick minimum i use thicker if the floor hight wont be too much or if the floor isnt as sturdy as is required.

Stirling board is no good, marine plywood is too expensive, British Standards is 18mm ply but use 12mm exterior ply for the job srewed down every 300mm, that will be ok

Minimum of 6mm backerboard is ok as well.BAL recommend it's OK on chipboard,but not on T&G.On T&G it is then got to be a structural board,as Darren rightly sais,18mm BS.No need at all to board if using 2 part adhesive ( bag & bottle )

Originally Posted by tony TLC

there is a new product on the market called NO MORE PLY i use this its 6mm thick moisture resistant easy to cut and transport works out about £10 per 1200x600 board best product i have used if you need more info on it just pm me

Is that the strengthened polystyrene sheets? I have seen that around but looks a bit flimsy to me?

nae probs, use water proof adhesive, on top of any cheap muck, well screwed down , wife will want it changed in a fortnight anyway, best advice, go to the pub, from old mikey,

use no more ply "top product" components in marine ply can discolor the grout. coating both sides of the NMP with sbr will make it totaly waterproof and a 6mm sheet is as good as 18mm ply.

heres an epsert from a site on sterling board.note the piece in red.

Stirling board can be painted. Where a fine finish is required, factory sanded panels are available. With unsanded panels, the surfaces can be wire brushed to remove any loose wafers and resin deposits. Priming and top coating with oil based timber paint can give a good, although not perfect, finish. Water-based products should be avoided as they may cause some swelling of the surface wafers.

sterling board is not a suitable substrate for tiling onto as the suface is likely to delaminate when wet

sb is brilliant kit as its very stable and cheaper than ply but no good under tiles

bs on overboarding is 15mm ply min, the nearest size available in the uk is 18mm

better off overboarding with no more ply or 6mm backerboard

Originally Posted by smurf21

use no more ply "top product" components in marine ply can discolor the grout. coating both sides of the NMP with sbr will make it totaly waterproof and a 6mm sheet is as good as 18mm ply.

As yet a still unsubstantiated claim by NMP manufacturers. Asked for clarification of their tests but no one ever responded. Personally can't see how 6mm of a cement based board can claim to have the flexural strength of 18mm of ply, but I still stand to be corrected!!

Originally Posted by grumpygrouter

As yet a still unsubstantiated claim by NMP manufacturers. Asked for clarification of their tests but no one ever responded. Personally can't see how 6mm of a cement based board can claim to have the flexural strength of 18mm of ply, but I still stand to be corrected!!

i wondered about that too and went surfing for more info

apparrently its a deflection thing, under 15mm ply is flexible, which is right as we used 12mm ply to form gentle curves on the front of a counter

having seen the lovely way it followed the formers i wouldnt trust it not to follow any defects in a floor

also you cant shutter with 12mm ply as it bulges between the supports

6mm backerboard is slightly flexible too but for some reason doesnt have the same deflection as ply, i wouldnt like to try to curve it either as im sure it would break

6mm cementboard reduces deflection in a floor the same as 15 mm ply

Originally Posted by mikethetile

i wondered about that too and went surfing for more info

apparrently its a deflection thing, under 15mm ply is flexible, which is right as we used 12mm ply to form gentle curves on the front of a counter

having seen the lovely way it followed the formers i wouldnt trust it not to follow any defects in a floor

also you cant shutter with 12mm ply as it bulges between the supports

6mm backerboard is slightly flexible too but for some reason doesnt have the same deflection as ply, i wouldnt like to try to curve it either as im sure it would break

6mm cementboard reduces deflection in a floor the same as 15 mm ply

Thats very interesting Mike, can you point me to the info?

i will if i can find it again, ill have to go surfing as i didnt bookmark anything and it was in january i looked

mike

is it ok to put marine ply under tiles on a kitchen floor i will be putting a porcelain tile on top and one tiler said they will crack