Help Me Help with limestone - TilersForums.co.uk | Tile Forums

dahagsta · 16-09-2008

Got myself 15m2 of limestone to lay and was after some great advice before i start. I've looked around this forum and got bits of advice here and there but was after it all as advice to do the job from start to finish.

12mm tiles onto a wooden kitchen floor. Was going to lay down 5mm ply screwed 300mm centres.

What adhesive do i need, what/how do i seal the tiles i.e before i lay or after. What about cutting, does the water in the cutter stain the tile.

This is the 1st time i've layed a floor with a natural stone so i am in need of advice to do the job all the way. Sorry if i've waffled on.

TilingLogistics · 16-09-2008

You cannot use 5mm ply, BS states 15mm but you cannot get that so it has to be 18mm. Your alternative if you want to stay thinner is to use nomoreply or backer boards.

You have given us the thickness of the stone but no dimensions so in order to give you the correct advice regarding adhesive we need the measurements.

What sort of finish on the limestone, honed or polished? Do you know the name of it? All this helps regarding the best advice regarding sealer/presealers!

A bit more info and I can give you step by step help

Kev

CCTiling · 16-09-2008

Hi Mate. Firstly I would laying 18mm ply for maximum strength and the adhesive manufacturer will usually only guarentee your work if you do this. I would use Bal rapid set flexible white as the adhesive. If you don't use a rapid set it may stain the limestone. Sealing the stone is carried out before and after grouting and you can buy a limestone sealer from most tiles shops. Topps sell a limestone sealer by Fila. If you use this product it's just the matter of brushing it on or using a roller then after a few hours just buffing the tiles. Use a flexible grout. I usually go for a grout best matching the colour of the tile but that would be upto the customer and then seal again after grouting. Hope this helps. Good luck

Grace'sDad · 16-09-2008

First off - 15sqm is a reasonable area - check that there is no or very little deflection (bounce) in the floor - if there is then fix it 1st. Too much deflection will break the stone.

Don't ever ever ever ever ever ever ever ever EVER use 5mm ply (or any ply with stone - my opinion only here) 5mm ply will do stuff all to help but will do a lot to speed up ruining the floor!

If the floor is rigid enough, I would recommend fixing 10mm hardibacker boards as per the instructions - basically glued and screwed.

Adhesive - must be white to avoid staining and flexible, cement based. I use BAL rapidset flexible but you could use a single part flexible which will give you a longer bucket life. Use a proper flooring trowel. No need to seal before fixing as long as you work cleanly - keep a bucket and sponge to hand to wipe up any stray adhesive. Allow to set, clean 1st, allow to dry and then seal maybe twice as required before grouting.

As for cuts - all cuts have to be wet, unless you are a dab hand with an angle grinder?!

Word of advice - don't drag your bucket around on limestone - it can scratch easily!

Do it right - take your time - get it right and enjoy the results.
Use ply - cut corners and rush - BIG regrets!

**grumpygrouter** · 17-09-2008

I personally have got to the stage where I have decided not to lay natural stone on a wooden floor without a decoupling membrane. Don't want any uncertainty as timber floors do have potential for a lot of movement. This would be laid on top of the strengthening ply overlay.

TilingLogistics · 17-09-2008

Quote:

Originally Posted by grumpygrouter

I personally have got to the stage where I have decided not to lay natural stone on a wooden floor without a decoupling membrane. Don't want any uncertainty as timber floors do have potential for a lot of movement. This would be laid on top of the strengthening ply overlay.

I would agree with you there Grumps but it has to be sold to the customer. I used to carry a small piece of ditra with me and a house brick to demonstrate that usually sold it to them

Kev

CCTiling · 17-09-2008

Quote:

Originally Posted by grumpygrouter

I personally have got to the stage where I have decided not to lay natural stone on a wooden floor without a decoupling membrane. Don't want any uncertainty as timber floors do have potential for a lot of movement. This would be laid on top of the strengthening ply overlay.

Hey Grumps. Haven't used this method before. Would you still have to lay 18mm ply to strengthen the floor or could you go less coz of membrane?? What thickness is the membrane and where would one buy it from?? Cheers Ross

Alberta Stone · 17-09-2008

Schluter makes the polyethylene membrane, but the chlorinated polyethylene material is vastly superior.

NobleSeal® TS

Thin-set waterproofing membrane

Noble Deck

Exterior thin-bed waterproofing and crack isolation

ditra is a good product and works very well for natural stone that is fragile.

Branty · 17-09-2008

[quote=TilingLogistics;124264]I would agree with you there Grumps but it has to be sold to the customer. I used to carry a small piece of ditra with me and a house brick to demonstrate that usually sold it to them:thumbsup:

Kev[/quote]
How does that work?

TilingLogistics · 17-09-2008

Quote:

Originally Posted by Branty

How does that work?

Stuck the Ditra to the brick then a piece of tile to the ditra showed them the movement and the dovetails in the ditra and the way it worked. Had it fixed to ply first but kept losing it in the van

So did it on a brick and it doubled up as a door stop for the garage door as well and i never lost it

Kev

**grumpygrouter** · 17-09-2008

Quote:

Originally Posted by CCTiling

Hey Grumps. Haven't used this method before. Would you still have to lay 18mm ply to strengthen the floor or could you go less coz of membrane?? What thickness is the membrane and where would one buy it from?? Cheers Ross

Ditra/durabase is about 3mm thick. The 18mm ply adds strength to reduce deflection which ditra/durabase has no effect on. It is the lateral movement of the timber that may cause the problem due to changes in atmospheric conditions.

For Durabase, check out our friend Wetdecs, or for Ditra CTD if you have one in your area.

CCTiling · 17-09-2008

Thx mate. I have a CTD so it's worth mentioning to my future customers about the product.