Large Tiles - Bed thickness

[lordswood]

Would a 9mm notch be OK for fixing 450x315 ceramic wall tiles in a domestic
wetroom?
The concrete base of the wetroom has been formed to slope toward a central gulley so I'll have quite a few diagonal cuts. To give myself some leaway, would a 20mm notched bed be OK for laying the 450x450 floor tiles?

 

[wetdec]

Hi

An 6/8mm on walls and 10mm on floor should be ok.

Is it a new concrete screed ? how were you thinking of tanking the walls ?

tiler

..

 

[grumpygrouter]

Welcome to the forums Lordswood. would you be kind enough to introduce yourself in the New Members bit telling a bit about yourself. Cheers.

QUite big tiles for the walls there, I assume you are using powder adhesive? Big notch trowels are only really required on the walls if they are abit iffy, I agree with wetdecs sizing as a general rule.

20mm notch on the floor will consume so much addy you may need to mix in a concrete mixer. Again is the floor flatness a bit suspect? You may find a 10mm half round sufficient.

grumpy

 

[GazTech]

Hello Lordswood,
Welcome to the forums..........Gaz

 

[lordswood]

Thanks for that Wetdec.
Both the concrete floor (5 weeks) and plaster walls (4 weeks) are new.
I was going to prime the concrete and walls with diluted APD and then put a further undiluted coat of APD on the walls, followed by a coat of WP1 on all wet area surfaces, plus taping the wall/floor joints.
Could you recommend a good BAL floor adhesive for this task given that the tiles are on the large side? I'm not a pro, and spoilt for choice with their range of products. This wet room is a separate area in a new brick built garage and will be used infrequently.

 

[GazTech]

Thanks for that Wetdec.
Both the concrete floor (5 weeks) and plaster walls (4 weeks) are new.
I was going to prime the concrete and walls with diluted APD and then put a further undiluted coat of APD on the walls, followed by a coat of WP1 on all wet area surfaces, plus taping the wall/floor joints.
Could you recommend a good BAL floor adhesive for this task given that the tiles are on the large side? I'm not a pro, and spoilt for choice with their range of products. This wet room is a separate area in a new brick built garage and will be used infrequently.

I would highly recommend this adhesive for your project....Gaz
BAL PTB (Pourable Thick Bed) Flexible

A highly polymer modified, flexible, rapid-setting, water-resistant, frost-resistant floor tile adhesive, especially suitable for fixing tiles, including fully vitrified and porcelain tiles to low porosity backgrounds and bases. Sulphate-resistant, cement-based, pourable, thick-bed solid-bed floor tile adhesive suitable for fixing ceramic tiles, quarries, natural stone and terrazzo in interior and exterior situations. Its consistency makes it particularly suitable for fixing large tiles and those with profiled backs. Back-buttering is not necessary. Suitable for use on concrete, cement:sand screeds, ceramic/quarry tile/terrazzo/hard natural stone, plywood overlay, vinyl tiles/sheet, mastic asphalt. BS EN 12004 C2F Adhesive

Coverage: Grey - ‘Thick bed solid bed trowel’ = 5.4kg/m²
Grey - ‘Large format trowel’ = 8.3kg/m²
White- ‘Thick bed solid bed trowel’ = 4kg/m²
White - ‘Large format trowel’ = 7.3kg/m² Bed Thickness : 3-25mm Open Time: 20 mins Setting Time: 3 hours Packaging: 20kg bags Shelf Life: Grey 6 months when Stored in normal dry conditions. Protect from damp.
White 12 months when Stored in normal dry conditions. Protect from damp. Temperature Resistance: -30°C to 100°C Colour: Grey / White

The Bal 10 Year Guarantee
Click here to download Material Safety Data Sheet
Click here to download Product Data Sheet
Click here to download

 

[Perry]

Gaz PTB :lol:

 

[lordswood]

Hi Grumpy,
I've filled in the necessary for new recruits.
I was going to use BAL Single Part Flex (White) for the walls. What advantage does powder have over ready mixed? Is the tubbed stuff weaker?
Thanks for your response on trowels and I'll get myself a 10mm half round.
The floor is not large (6' x 5') and it won't need many tiles at 18" sq but bearing in mind the size of each tile, and the concrete base has been 'fashioned' by the builder to include slopes towards the central drainhole, I may need a thicker bed in places as well as the diagonal cuts.
----
<P>Hi Gaz,</P>
<P>Thanks </P>
----
<P>Hi Gaz,</P>
<P>Cheers&nbsp;for the welcome and thanks for the PTB recommendation. Much obliged.<IMG alt=0 src="http://www.tilersforums.com/images/smilies/thumbsup.gif" border=0 smilieid="334">&nbsp;&nbsp;</P>
----
Gaz,
Haing

 

[lordswood]

Gaz,
IF PTB is pourable will it still notch like wall adhesives? I've never tiled a floor before (as this question has probably proved!)

 

[GatesheadCol]

Dave will be along any second with the techy bit :8: but for large format tiles the tubbed gear is not strong enough to hold the weight of the tile. is that right Dave.?

PLus it sets faster of course which means you canb groiut quicker too.

But i belive the main reason is the weight of the tile is too great for tubbed adhesive to hold while it dries, remembering that it takes ages to fully cure
----
Oh and nearly forgot Lordwood dont forget to put the drain slope into the tiles too if you get what I mean. Im sure one of the moderators will provide a link to a very good diagram showing how to cut the tiles and lay then so they slope towards the gulley/drain

 

[lordswood]

Cheers Col......understood. I've mapped out the cuts needed for the trap and the corner-to-corner diagonals for sloping the adjacent tiles. It looks good............on paper!

 

[GatesheadCol]

It'll be fine mate

 

[Burnsy]

Tubbed adhesive goes of by air. So when you have a large tile, like you are using the air is trapped in the middle of the big tile and has no where to go and therefore will take an age to go off. A cement based adhesive cures by a chemical reaction - the cement / polymers & water crystallising with the plaster (at microscopic level - read that somewhere):yes: .

I would recommend a standard setting adhesive for the walls - Gaz from BAL will recommend one. BAL Technical state that any tile over (300 by 300 - Large format) a cement based adhesive should be used. Depending on the colour of the tile and grout will dictate what colour adhesive you should use. Bagged aghesive is also better for walls as it is easier to trowell. Also if you are using a tubbed on walls that arn't even, and you need to pack out a tile with adhesive (cheating, i know), the adhesive behind the tile will never really go off, whereas if you use a cement based this will set like a rock. Much better product overall

I would also use a 20mm notched trowell for the floor with tiles that size - you will get about 3m sq per 20kg bag.

good luck

 

[grumpygrouter]

Tubbed adhesive goes of by air. So when you have a large tile, like you are using the air is trapped in the middle of the big tile and has no where to go and therefore will take an age to go off. A cement based adhesive cures by a chemical reaction - the cement / polymers & water crystallising with the plaster (at microscopic level - read that somewhere):yes: .

I would recommend a standard setting adhesive for the walls - Gaz from BAL will recommend one. BAL Technical state that any tile over (300 by 300 - Large format) a cement based adhesive should be used. Depending on the colour of the tile and grout will dictate what colour adhesive you should use. Bagged aghesive is also better for walls as it is easier to trowell. Also if you are using a tubbed on walls that arn't even, and you need to pack out a tile with adhesive (cheating, i know), the adhesive behind the tile will never really go off, whereas if you use a cement based this will set like a rock. Much better product overall

I would also use a 20mm notched trowell for the floor with tiles that size - you will get about 3m sq per 20kg bag.

good luck

Hi burnsy, we talking about the same size trowel here? my 10mm half round is the same as your 20mm? i.e 20mm dia, but only 10mm deep?

Grumpy

 

[Burnsy]

My 20mm nothced trowel - large format trowell. Think there different mate.

i've got a 10mm round notched trowel - used for tiles 300mm by 300mm. Anything bigger i use my large format 20mm nothced trowel.

The large format trowel is 20mm deep - gives a huge bed of adhesive.

I also use Platinum trowells now, there a mint bit of kit - great coverage