Basic question - flooring prep

[edwardk]

Hi guys,
Got a kitchen to tile - about (some pics here and layout http://www.tilersforums.com/tiling-forum/45729-tile-orientation-600-x-400-way.html#post470936)

I still haven't started (busy with work again) but am keen to get started.

I was wondering if I needed to do any floor prep?

It's a screed floor and looks pretty flat to me. What is the best way of working out any bumps/dips?

What kind of dip is acceptable ?
Do you just add more adhesive or is it advisable to get it as flat as possible with SLC?

I've got Ardex X77W and was planning on mixing up a small amount and just working slowly with 3mm tile spacers (applestone limestone) and doing the cuts as I go along.

Then covering it with plastic overnight until it's finished (muddy cats etc).
Once tiles are down I was going to seal with LTP Mattstone then grout then seal again.

Got some ducts with ply covering them.
What is the best way of making sure I don't have any movement cracks?
Just make sure it's all level and solid or go lower and then backfill with SLC ?

Alot of questions - thanks for any help.

Ed

 

[White Room]

To find if it's flat lay a 6ft level on the floor and check for any lumps or dips under the level but check the whole floor, if it dips with about 5mm I'd use slc...

I would use dural C1 decoupling membrane for the limestone and even seal atleast 1 coat before laying, limestone can mark very easily and use a white adhesive

 

[Daz]

Applestone limestone is very light in colour and does mark easily so deffo seal at least once prior to fixing. I'm pretty sure that Ardex X77W is a standard set adhesive so just mix up a decent sized bucket and don't tread on your tiles until the next day (just read the instructions on the bag).

Good luck,

Daz

 

[White Room]

I would use a fast set

 

[Daz]

I would use a fast set

Me too, but Edward states that he already has the X77W.

 

[White Room]

Change the addy mate:smilewinkgrin:

 

[Stewart]

Fast set for me too........

 

[edwardk]

Thanks for the advice - can't change the X77W but not too bothered as have moved the kitchen to another room. I'm a slow worker too and haven't tiled before so I think I should be ok with it.

I guess my main question now is whether to use a decoupling membrane or not.

Just looked at some youtube vids on schluter ditra and dural ci matting.



So if I didn't have any plywood ducts then it would be a simple case of self leveling compound in the dips and then adhesive+tiles.

Am I right in thinking that due to the ducts I have to use a decoupling membrane?

The schluter dita is £12.95 locally and the Dural CI matting is £9.95.

Are they both pretty much the same ?

What is the correct adhesive for putting the decoupling down with?

I guess if I don't put the decoupling down then I'll get cracks in the corridor and kitchen threshold. I guess a couple of hundred extra pounds is worth it for no cracks in my own house

Any thoughts?
Ed

 

[Diamond Pool Finishers]

yes ED use Dural they are a site sponsor and they are cheaper!! i just used a load and i used a fast setting addy to stick the matting down ,make sure you lay it the right way up IE the netting/holes-up side and the fleece down this is very important then as you UN-roll it into the wet-addy have a clean trowel to iron out on the top/clean side any air/or voids between the matting and the addy for a great bedding/fixing to the floor then you are ready to Carrie on tiling mate straight-away

 

[edwardk]

The local shop sold me Ardex P51 primer and then Ardex X7R for bonding down the matting.
Still waiting for the matting as they sell 30 m2 of Dural CI for £300 and I've seen places online for about £170.

Do I water down the P51 then paint it on the screed and let it all dry - THEN mix up small amounts of X7R and lay the matting in strips?

Thanks
Getting there...

 

[Daz]

Okay, I've only skimmed this thread to remind myself so apologies if I've missed certain details..

Apply P51 undiluted to wooden substrates. It is suggested that you mix it 1 part primer to 3 parts water for sand cement screeds.

The X7R will present a challenge for you (I'm not trying to scare you, just prepare you). I find that it goes off really quick so deffo only mix up small quantities.

Lay out your decoupler, cutting the strips to fit your rooms before mixing any adhesive. I usually draw a line down the edge of the individual strips so that I know what area to trowel the adhesive into for each section. I would suggest mixing the X7R slightly "wetter" than recommended on the bag and only use a mosaic (4mm) trowel for spreading the adhesive, making sure that you remove all air pockets and achieve a solid bond.

I think that covers it, good luck,

Daz

 

[edwardk]

Thanks Daz - do I let the P51 dry ? (leave overnight?)

Thanks for the heads up on the adhesive open time - they told me in the shop to be careful but wasn't sure about a 4mm trowel...

 

[Daz]

The P51 will be dry in about an hour Edward.

Good luck and don't forget to post some pictures for us.

 

[edwardk]

Top marks for these guys :

Good prices and nice service - seemed to get some high prices from others - here's a quick breakdown for those interested:

30 sq metres ditra mat : £
10 litres LTP Mattstone : £
shipping : £
total : £

Locally they wanted £ for 30m2 of CI Matting....and £ for 10 litres of Lithofin MN stainstop... total : £....

So pretty damn happy about saving a bit
Ed

 

[nybor62]

hi edwardk imo the ardex x77w is not the best choice for laying lime stone tiles, the ardex you have got is for tiles with a low porosity,
cant you swap for a rapid set addy, which eliminates the chance of moisture staining the stone