Basic advice needed - Tile Advice

[DIY Rich]

Hi,
I have read several threads, but am still unsure of what to do with my bathroom.
I have 400mm x 400mm X 9mm porcelain tiles to use on my bathroom walls. The walls are bare brick, but uneven so I am going to batten them and screw boards onto this.
I haven't bought the boards yet, and was thinking of buying moisture resistant boards for this (they seem a lot cheaper than backing boards) but am undecided.
If I use these boards, I can't decide whether or not I need to prime them prior to tiling from the forums because it seems that opinions differ???
I have bought mapei flexible tile adhesive for the job which looks like good stuff at £30 for 20kg bag in B&Q.
I don't know what size notched trowel I should use for these tiles, bearing in mind that the boards will be nice and flat???
I am now wondering about the drying issues talked about on the forums with such a big tile, and whether this will be an issue for me?
I think that the differing forums have confused me a bit, so am hoping for some good comprehensive advice if possible.
Many thanks,
Rich

 

[Martyn Leeds]

I'd be dot and dabbing the walls if they're back to brick.

8 or 10mm trowel for me, & drying time shouldn't be of any issue unless its -5 in your bathroom

 

[Qwerty]

As above. Dry lining the room would be so much easier. Use standard 12.5mm square edge plasterboard.

A 10mm trowel will be fine for your requirements.

If the adhesive you have is rapid setting, I would look to exchange for a standard setting polymer modified adhesive instead. Flexible adhesive isn't essential for your requirements.

 

[WetSaw]

Beat me to it regarding "Dot and dab" being a method to attach the plasterboard not the tiles!!

If you're tiling a wet area then you'll need tank the plasterboard before tiling ( ideally..)

 

[DIY Rich]

Thanks for the replies.
I was planning on putting batons on the wall rather than dot and dab because I read with this weight of tile the board should be attached mechanically.
I think it was on this forum.
Do you guys not agree?
The adhesive is Mapei Super Flexible Adhesive and isn't rapid set. I bought this because our local B&Q is closing down so there was 40% off (3 of the bags cost me £1 each because they had small holes in the bags) they had sold most of the other stuff and this looked pretty good.
I guess I need to buy another trowel then as mine is 6mm.

 

[WetSaw]

You can mechanically fix through the dabs once its set. If your walls are that uneven it's much quicker and easier to d&d rather than trying to get battens straight and level before boarding.

 

[widler]

If you prep the wall (if its old block or brick) pva it 1st , then dott and dabb the walls , they will hold a elephant up .
If you screw battons on the wall and screw the boards on the battons its only the srews holding the boards up .
Trust me dry wall addy stuck is like 2 week old baby poo stuck to a blanket

 

[MTiler]

Board with waterproof backerboard and you wont need to to tank them, just tape the joints.

 

[Old Mod]

On the point of your adhesive with the holes in the bag, make sure you mix it exactly as instructed, and if it won't mix in to a smooth consistency, bin it, esp if it's near it's expiration date.
And if you do use the waterproof backer boards as Sharon suggests, make sure you tank over the mechanical fixings as well as the board joints.
It is an easier method for home DIY.

 

[White Room]

If you buy moisture resistant boards they only come in 8x4's, personally I'd use standard plasterboard 6x3x12.5mm because there going to be a lot easier to handle and then tank.