Substrate weight ratio / bonding - Tile Advice

[James De]

hi all,

So from my notes plaster can only take 20kg per m2 (including adhesive/grout).

I’m just about to tile a wet room and my issue is this:

I’ve had the room skimmed (it’s mostly a stud wall room with plasterboards, part of one wall is block). This same part block/ part stud wall had to be brought into line with bonding to square it up. On the thickest side the bonding is around 1 inch thick, on the thinnest side it’s about a 3mm skim.

Now the customer has just changed her tiles and wants 1200x600 porcelain tiles put up around the shower area (they’re 35.5kg per 1.44m2), one of the walls being the bonded wall. The rest of the walls are 10mm 150x400 ceramics.

Am I best fixing backer boards on all walls? My next issue is I have no idea where the studs are to fix the boards to.

Any help and advice would be great!!!!!

 

[The Tiler]

overboard the lot, can't fix onto bonding anyway.
find the studs first, drill holes to locate them and level up and mark. Screw and raw plugs into solid wall. Washers maybe needed for backer boards depending on the type used.
tank room or joints depending on the boards.

 

[James De]

overboard the lot, can't fix onto bonding anyway.
find the studs first, drill holes to locate them and level up and mark. Screw and raw plugs into solid wall. Washers maybe needed for backer boards depending on the type used.
tank room or joints depending on the boards.

Cheers mate.. out of three of us that I’ve kept in contact with after doing the course, I’m the only fecker getting these challenging jobs ‍♂️

 

[The Tiler]

the challenging jobs are the best ones, gets very boring, imho, if they are all easy.

 

[James De]

the challenging jobs are the best ones, gets very boring, imho, if they are all easy.

Lol this is only my 3rd job and none have been easy.. I’d kill for a straight forward one haha but I k ow what you’re saying.. better off in the deep end from the get go.. can’t get worse than what I’ve had so far

 

[James De]

Out of curiosity, does the weight ratio of plasterboard get affected if it's skimmed? I can't find the answer any where, they just quote unskimmed p'board.

 

[The Tiler]

yes it does
plasterboards are 32kg m2
plaster is 20kg m2
I think

 

[Boggs]

yes it does
plasterboards are 32kg m2
plaster is 20kg m2
I think

It can also be affected by the tanking system you use.
Check with the manufacturer beforehand.

 

[Waluigi]

Tilemaster tanking doesn’t reduce the weight limit.

It’s one of the easiest systems on the market and one of the best paint on system IMHO

 

[Boggs]

Tilemaster tanking doesn’t reduce the weight limit.

It’s one of the easiest systems on the market and one of the best paint on system IMHO

I agree, by far the best I have used.

 

[James De]

yes it does
plasterboards are 32kg m2
plaster is 20kg m2
I think

I know p’boards are 32kg, but if it’s skimmed what does it become?

 

[James De]

Tilemaster tanking doesn’t reduce the weight limit.

It’s one of the easiest systems on the market and one of the best paint on system IMHO

ill have to have a look at that one, I use Ardex I think. Can’t remember seeing Tilemaster in CTD

 

[Waluigi]

To be honest, Ardex is a very good kit too.

I prefer TM for speed though.

 

[Boggs]

I know p’boards are 32kg, but if it’s skimmed what does it become?

20kg

 

[acaciaguy]

I don't skim plasterboard before tiling