New to Wedi / Jacko, advice needed on uploaded pic please - Tile Advice

[stuey72]

New to using Jackoboard and may have potentially dropped a bollock so wanted to check first.

The picture is an internal corner where a 800x800 shower enclosure is going. I have joined the boards with boardfix / wedi 610 and pulled the washers down just below the surface so they have dished inwards.

I have used Tilebacker self adhesive tape on the internal joints and the board joi.ts where they meet. I have done nothing with the washers underneath, the self adhesive tape has shaped into the washer depressions.

I have also (maybe wrongly) ran a full strip down the intermediate fixings, again not levelling of the depressions with Wedi 610 or tile adhesive. The studs are 300mm centres as the boards are 12mm.

Will this be ok as im concerned that the panels surface area is nearly a 1/3 in tape.
My concern would be if rhe butyl rubber underneath the woven cloth ever decoupled there wouldnt actually be much of a key (or I could be talking tosh!)

Thanks,

Stu

 

[Qwerty]

You should be fine with that. I have never used it myself.
In the future don't screw the washers in so much, they should be flat with the surface.

 

[stuey72]

Thanks for the reply,

So am I right that your saying the washer should sit proud of the board only by the thickness of the washer and not pulled into the board?

 

[One Day]

You'll be fine with that.
If only other wet areas were done so properly!
Good job.
Don't forget that your main weak area now is going to be your wall/floor joint.
Give that some proper care too!

 

[Qwerty]

Thanks for the reply,

So am I right that your saying the washer should sit proud of the board only by the thickness of the washer and not pulled into the board?

Yes, so only the dished underside of the washer pulls into the board

 

[One Day]

I screw them tight enough so that the whole washer countersinks - just.
I know it crushes the cement face (not a problem with Kerdi board!) but the cement face isn't waterproof anyway.
As long as you don't knacker the core by tearing it or compressing it far too much, it's fine.

 

[stuey72]

So in a non-wet area, I take it that its sufficient to tape the board joint fixings (600 board at 300 centres) with an alkali tape / tile adhesive?

What about the intermediate (centre fixings) in a non wet area?

I've seen another install where it looks like they have went mental with the Wedi adhesive and have spread it with a spatula over all the washers and created a 50mm wide strip of adhesive down the full length of the butted board joints with no sign of mesh tape whatsoever.

Will tile adhesive actually stick to that stuff?

Sorry for all the questions, just like to get me head round it.

 

[One Day]

Tile adhesive and scrim tape isn't sufficient in a wet area.
Tile adhesive isn't waterproof. Scrim tape is only to help with movement.
Ok, think in principles, rather than instructions.
You have waterproof boards, yet the gaps between them, and the holes made by fasteners can let water through.
Principle is - you stop that water getting through and you can only use waterproof materials to do that.
The manufacturer supplies 2-part waterproof adhesive, tape, and polymeric adhesive (610).
There are different thoughts on here as to what best to do with those. Personally, i tend to combine depending on the job at hand and the materials at hand.
Too much 610 all over the boards would be bad for cement adhesive to bond to, you're right. But so long as you can still get a good grab on the boards, you don't have to be ocd with where it gets.

 

[One Day]

If it helps illustrate, here's one I've done recently.
I didn't prepare this room, hence the reason i won't tile it. It's one of 24 in a hotel being refurbished. I'm just waterproofing the builder's efforts so i faced here a mixture of green plasterboard, Jacko board, impey tray.
I used Kerdi membrane onto the tray, fixed with ardex wp. Wall was tanked with ardex wp. Tape is a generic fleece tape. Corners i made myself. Board joints were scrim tape but with generous amounts of ardex wp. Screw heads simply smeared with 610.
It's not a pretty job and it contravenes everything about manufacturer's 'system approach' but I'm confident it'll never leak unless damaged and I'll guarantee it myself.

 

[stuey72]

A picture paints a thousand words, looks watertight to me!

Thanks Impish for taking the time out to advise me, it is greatly appreciated, thank you.

I've enough self adhesive waterproof tape left so that will go on all the joints around rhe bath area as the new bath has a shower head on it. The board joints in the dry areas will get adhesive and tape. Intermediate fixings in the dry areas will either get a dab of 610 or just left as they are.

The entire room is getting done out in 12mm on the walls as the tiles are 600x300x10 ceramics and the existing plaster and paramount boards were rough to say the least.

The original install had failed as the original tiler ( or hopefully homeowner) had dot and dabbed the tiles straight onto a plaster and paramount wall with no tanking whatsover.

The grout joint had failed in the shower cubicle and water had seeped through and turned the plaster to mush. Even worse the water then tracked through the internal brickwork, soaked the cavity wall insulation and eventually soaked the outside brickwork. Unbelievable.

This is why I need a belt and braces approach to rhis to reassure that they wont experience a repeat of the above!

Thanks again Impish,

Stu

 

[White Room]

The left hand board bulges a tad in the centre, don't know the size of tiles your fixing but it may cause problems.

 

[SJPurdy]

When using the washer fixing system the washer should be pulled down to the board surface with the screw, it should then be tapped with eg a rubber mallet to break the outer rim of the washer into the surface of the board and then finally the washer should be pulled flush into the board using the screw.

 

[stuey72]

The left hand board bulges a tad in the centre, don't know the size of tiles your fixing but it may cause problems.

Ha, that had me running for the spirit level! No its fine, combo of camera angle and the tape not running in parallel lines must be giving the illusion that its bulging out. Phew.

 

[stuey72]

When using the washer fixing system the washer should be pulled down to the board surface with the screw, it should then be tapped with eg a rubber mallet to break the outer rim of the washer into the surface of the board and then finally the washer should be pulled flush into the board using the screw.

Thanks, came across this last night, Marmox info if i'm correct?

Fair play to them for apparently being the only manufacturer to elaborate on the fixings in their literature.

 

[SJPurdy]

Thanks, came across this last night, Marmox info if i'm correct?

Fair play to them for apparently being the only manufacturer to elaborate on the fixings in their literature.

Wedi was my source, an old printout in my file taken from their website.