Dot and dab to brickwork

[rj1884]

Good afternoon.
Just started a bathroom which has resulted in the plaster/sand and cement falling away from the brickwork on the external wall in the walk in shower area as we removed the existing tiles. We've striped the wall back to the brickwork as the wall was so bad. We intend to dot and dab using a backerboard. My question is is there a specific adhesive I should be using to stick the boards or would any cement based adhesive do. Also would you guys mechanically fix the boards as well for extra security.
Thanks in advance

 

[CJ]

Not ideal hardi backer. You can dot/dab marmox and then screw when dot have dried.

 

[rj1884]

Sorry should have mentioned. We're using dukka board as oppose hardie. Would thickness would you use.

 

[diamondtiling]

You using hardi? if so driwall adhesive plus mechanical fittings, seal up the joins and internals and away you go. Knauf aqua panels say on the label not to fix using dot and dab system (used to anyway)

Here is one I did..

 

[rj1884]

Very nice mate. I've spoken to dukka board technical and they've mentioned you can dot and dab there boards but they're to be mechanically fixed as well.

 

[CJ]

They recommend 20mm if wall is rough.

[DLMURL]http://www.dukkaboard.com/pdf/Dukkaboard_06_solid_walls.pdf[/DLMURL]

 

[diamondtiling]

Used Dukka board a lot in commercial shower areas because its so quick to install, 100mm boards to use on the floor create instant falls to full length drains. 20mm on the walls as CJ says using the screws and washers that come with the boards.

 

[rj1884]

Thank you for your quick responses.

 

[rj1884]

What thickness would you use on a stud wall.

 

[diamondtiling]

I cant remember all the sizes but its incredibly strong material, 20 mm sounds right but if they do 12/15 mm these should be fine with plenty of timber behind them to eliminate bounce.

 

[CJ]

Min 12mm.

 

[IHB]

Fixing instructions etc in their [DLMURL="http://www.dukkaboard.com/Catalogue.php"]Dukkaboard[/DLMURL]

 

[thompsonbrown]

Used Dukka board a lot in commercial shower areas because its so quick to install, 100mm boards to use on the floor create instant falls to full length drains. 20mm on the walls as CJ says using the screws and washers that come with the boards.

Is that tile safe membrane on the walls? When I did my impey training we were taught to do it that way. Then the company sent out a letters asking us not to.

 

[diamondtiling]

Is that tile safe membrane on the walls? When I did my impey training we were taught to do it that way. Then the company sent out a letters asking us not to.

How else could you do it? It is a great product (expensive) but it did the job. When I fitted it I had reservations because after 3 hours I could still peel it back, the next day though it was stuck and was not coming off at all.
What were the reasons not to fit it this way?

 

[rj1884]

What would you recommend for priming the brick work.

 

[diamondtiling]

I use acrylic primer mate

 

[rj1884]

Cheers mate. Was thinking doing it that way. Much appreciated.

 

[thompsonbrown]

How else could you do it? It is a great product (expensive) but it did the job. When I fitted it I had reservations because after 3 hours I could still peel it back, the next day though it was stuck and was not coming off at all.
What were the reasons not to fit it this way?

I done the Impey training about 15yrs ago when I sub-contracted for dolphin bathrooms.
6 months later Dolphin sent out a letter to all there fitters from Impey advising not to use the tile safe membrane on the walls due to several failures. I thought that was still there Reccommended advice. I did about 10 wetrooms with the membrane on the walls and never had a problem. Think theres a Impey Sponser on this site might be worth asking the question.

 

[diamondtiling]

Well that may be true but they still advise the same fixing methods. I was unhappy with their tray fixing advice and changed it to suit the installation. No problems yet.

 

[thompsonbrown]

Well that may be true but they still advise the same fixing methods. I was unhappy with their tray fixing advice and changed it to suit the installation. No problems yet.
View attachment 57456 View attachment 57457

Nice job by the way. Is that true ? do they say tile safe the walls.

 

[thompsonbrown]

Nice job by the way. Is that true ? do they say tile safe the walls.

found this on the forum from 2008
If it wasn't for that letter I recieved I would never have found out.

Impey UKGuest [h=2]

Impey Tilesafe Membrane[/h]

Hello all, as you can see this is our first post on this site. After scouting through various posts one thing seems apparent and that is confusion surrounding how, where and to what height the Impey Tilesafe tanking membrane should be installed.

To set the story straight - at Impey we "recommend" tanking the entire floor of the wetroom, although as a minimum requirement you must tank into and at least 1m beyond the wet area of the shower zone.

Although in our opinion Tilesafe is the ultimate wetroom tanking membrane for wetroom floor applications, it is not suitable for tanking the walls in areas where the vertical tile loading is likely to exceed 20kg/m2 - which rules out most natural stone/travertine/marble etc.

The Tilesafe tanking kits we provide are supplied with a roll of 150mm wide jointing tape - this should be folded along it's length to create a 75mm overlap onto the floor and 75mm upstand at the wall. This is sufficient for the Tilesafe application. For the tanking of wetroom walls we recommend you use an alternative liquid or fleece tanking system or a waterproof backer board.

The Impey Tilesafe membrane remains stable up to 32 degrees C. And for this reason we only recommend the use of the 100 watt Devimat under tile heating system when using Tilesafe. There is no need to apply a self levelling compound to 'protect' the membrane from going soft (as it's a rubberised bitumen based sheet).

The membrane is applied directly to the floor/wetroom floor former and then the UFH is applied directly to the top of the membrane. Then you can tile straight over the top as there is no curing time.

I hope that helps to clear things up a bit ​

 

[diamondtiling]

From 2008? The instructions they sent me stated to fix the membrane directly to the walls after fitting the corner pieces. A 2mm gap was allowed for so there is no overlap, this is filled with a waterproof sealer that they supply.
I spoke with Impey and their technical dept talked me through my queries as I was unsure if it would hold the tiles (1000mm Porcelain)
Its still up 12 months later and to be honest I cannot see any problems, it stuck like the proverbial to a blanket.