General questions from a diyer...

[andrewt]

Hi all.

I’ve tiled previously (ceramic tiles on walls only), with what I would deem as success. However, the more you read up on the subject, the more you find out there is to learn and so I want to do my current bathroom properly.



I’m about to tile above my bath, where there will be a mains/combi-fed shower. I will be tanking the walls with BAL WP1, then BAL single-part flexi for 8mmx20cmx50cm ceramic tiles, then BAL microflex grout. The walls are skim plaster on both plasterboard & solid wall.



As you are all very helpful, I’d like to ask a few specific questions if I may:



1)How would I prime the plaster for tanking? Do I dilute? How many coats?

2)If I run out of the actual waterproof material (as the side of the bath is 1700mm and the wall goes on beyond that), can I just feather it out to “nothing” the further away I get from the actual shower? I suppose that would mean I’d need to prime undiluted with two coats, as bagged adhesive would then touch the primer.

3)You get tape with the tanking kit. I’ll use it in the inside corner, but do I need to use it anywhere else?

4)Solid bed thin bed trowel??? Does this equate more or less to a standard notched trowel (ie 6mm’ish)?

5)When using the notched side of the trowel on the adhesive, do you scrape it back to the wall or do you have to leave a film of adhesive all over the wall?

6)Holes for the shower pipes. What is the usual method to make them waterproof?

7)Can I really mix up single-part flexi and it remain useable for hours when in a bucket???!!!

8)Lastly(!), when it comes to edging strips, I never know whether they are meant to sit flush with the tiles or just sit proud of them. Sitting proud would hide any cut ends of tiles, but it stands out a bit.


Many thanks for your help with these beginner’s questions and sorry there are so many!

 

[Andy Allen]

prime with bal apd primer, then tank walls after 15-30 mins, one coat on the walls, 2 coats over the tape, should have enough to do round the bath, use tape round corners and pipes, i would go 8mm notched trowel, adhesive will stay fresh in the bucket you mix it in as per instructions,and flush trim looks best imo..

 

[andrewt]

cheers for your reply mate, much appreciated.

 

[andrewt]

Hi, just a question - what about laying the adhesive on the walls. Do I scrape back to wall with the trowel so there's only ridges, or do you leave a mm or two on the wall in all places?

 

[beanz]

45 degrees, hard to the wall, or you'll end up with different depths.

 

[andrewt]

Will do, thanks. But will this mean the trowel scraping off adhesive where it touches the wall, leaving only the notches / ridges of adhesive?

I'm sure I read somewhere that coverage should be 100% for wet areas, but maybe this happens when you compress the tile onto the ridges?

And lastly, square-edged or round notches?

So many questions in my head!

Many thanks for replying.

 

[Andy Allen]

when you bed the tile on the wall give it a little twist, this will make sure the ridges squash and take up the space the notch makes, if you know what i mean, you can spread some adhesive on the back of the tile too, using the flat side of the trowel, this is called back buttering..

 

[bugs183]

Hiya Andrew.
Andy said it all there perfectly!
Round notch seem to spread slightly better, but it will be subjective at that depth.
As Andy says trowel the adhesive firmly with the notched trowel onto the wall, the notches then give the adhesive a good mechanical key due to the scratching action.
This is why putting adhesive onto the tile and putting this to a wall with no adhesive on is not recommended.

 

[andrewt]

Cheers both.

I'm with you now. Lay on, notch up (with the notches standing proud (!) and the hollows more or less back to the wall. When the tile goes on, the notches squash down to fill the voids left by the hollows. Hey presto, no voids left.

Thanks again.