green chipboard floor help

[andypar]

Hi, i have a green chipboard 22mm floor that is on joist, that are screwed to concrete and are really solid, and am going to put down 40m2 of quartz tiles. The problem i have is i don't have room to overboard or if i did maximum would be 3mm, what is the best adhesive to use please. I have sanded a test area and moisture will penetrate this area a lot better than where i have not sanded.
Thanks, Andy

[jwatson]

if you tile straight onto them boards you will have problems! 3mm ply will be useless. a sheet of paper would be more use. the minimum over boarding you will be able to use will be 6mm tile backing boards and I am sure a de-coupling membrane would also be a very useful addition to your fixing method. BAL, mappei and weber are all good adhesives each have there own names for the adhesive you require for these tiles.
your end result will only be as good as your prep work, cut corners at your peril.

[andypar]

thanks for quick reply, i was worried this might be the answer, has anyone used nicobond plastic ply as this is only 3mm thick,
thanks again jwatson

[jwatson]

i have never used that product but there is tilers on here that have a bit of debate about this product really.
here is a link to one of the pages with this product being discussed Plastic ply

[Dave]

You can use Ditra or Dural Ci+ Stuck down with an S2 adhesive, then tile with a suitable adhesive for resin bonded tiles.. I'e.. Mapei Granirapid or Elastorapid..are 2 good ones..

[Rich]

I would over board with 6mm tile backer board myself, if this is not an option then a decoupling membrane is a good route but you MUST make sure that the floor is 100% deflection free. Any bounce will cause the tiles to crack and lift.

[andypar]

thanks for all the advice, 6mm overboard is too thick i'm afraid, i can only get away with 3mm, the floor is really solid , think Daves way may be the best option, the tiles cost a packet so i dont want to bodge it
thanks again , Andy

[Rich]

You can say thank you to the members by clicking on their little "Thanks" button at the bottom left hand side of each post.

Let us know how you get on and be sure to come on here and get all the advice you need through out the project

[andypar]

hi , does anyone know what would be the overall thickness using durabase ci matting to fix the quartz tiles , thanks, Andy

[Rich]

I believe its 3mm but I could be wrong.

[Phil Hobson]

Hi Andy, how thick is the quartz? CI matting is 3mm laid with 3mm/4mm notched trowel so if you allow 1mm/ 2mm under the mat, and 3mm on top for tile bed, plus the tile thickness. I must add to the above comments chip-board is bad news for tile installations sorry

[andypar]

thanks Rich, i was wondering if it would have been more with fixing the matting and then the tiles, 3mm or even 5mm in total would be great so sounds ideal, thanks Andy

[andypar]

thanks Phil , thats great, the tiles are 12mm , i have 20mm under the bi fold doors to the seal so will work out ideal, all the best, Andy

[andypar]

the grey fella in Phils post looked like me when i looked at the price of the matting

[Phil Hobson]

Andy we have Dural as sponsers on the forum, they may be able to cut a deal. Price tends to go off volume, if you have 40m2 to do a 30m2 roll and a 10m2 roll. Give them a call. Better to get it right at the begining imo, good luck

[doug boardley]

I'd be thinking of removing the chipboard and tiling onto the concrete, maybe using something like weber floor flex to build up the concrete to desired height.

[andypar]

thanks doug , but unfortunatly i have 90mm insulation with 90mm x45 joist screwed down to the concrete ,

[Rich]

Is there any chance of replacing the chipboard with ply?

[andypar]

not really rich , i think i will sand the chipboard a bit and make a key and seal it ,then try a test area, use the matting and hope, now it is whether to tile under the kitchen units or not hmm, i was going to, but now am wondering if that would be such a good idea.

[Gall.B]

i think i will sand the chipboard a bit and make a key and seal it

Remember Andy no PVA, a good primer

[andypar]

thanks gall, i was thinking of mapei prim t ,unless there is another that anyone can recommend or would mapei primer G be better, thanks, Andy

[Gall.B]

I like to stick to the same brand as the addy, Either Weber, Mapei, Bal or Ardex.

What is the meterage of the floor Andy?

[andypar]

40m2 gall,thanks

[Bathfix Bob]

I take it the height issue is due to UPVC french windows or something, eg that cannot be planned?

UPVC bi-fold door??

[andypar]

yes Bob, and a low threshold door which opens inwards, if only the mrs would settle for linol

[Gall.B]

You will need expansion joints if the floor runs anymore than 4m in any direction Andy.

[impish]

You can use Ditra or Dural Ci+ Stuck down with an S2 adhesive, then tile with a suitable adhesive for resin bonded tiles.. I'e.. Mapei Granirapid or Elastorapid..are 2 good ones..

Advice is good Dave and certainly something I would do, but I reckon you'll find Schluter would say no to using Ditra on P5 boards.
They also say use of an S2 adhesive to bond the Ditra cancels out the effect of the membrane. Should always be an S1. Bizarre I know - but true.

A good non flexible addy with a flexible admix will replace approx 50% of the water used in the mix. Resin bonded tiles are susceptible to twisting with too much water.

[andypar]

thanks gall, yes it runs 8.6m so i would have to put 2 in or would i get away with one

[andypar]

thanks impish, i have a bit of thinking on what to do now

[Rich]

You should only have to install an expansion joint every 4 or so M if the tiles are fixed over under floor heating, usually around every 7-10M. Not that it would do any harm to add more.