Wall preparation in new bathroom

[Matt K]

Hi there,

I'm renovating a room in my house (Victorian terrace in London) that I'd like to turn into a bathroom. I'm going top-down and I've pretty much finished building the roof - which wasn't in good shape, I'm now ready to start preparing the walls.

At some point in the past, the interior brick walls of the room have been covered with a layer of 20mm - 30mm of what I think is concrete, over most of the walls (up to about 2.5 meters high). That has then been painted and wallpapered over the years. I have a few questions before I start work, I'd really appreciate any advice as I'm learning as I go with all of this! I've attached some pictures below for reference.

1. Although the wallpaper/paint is quite well adhered (I do need a heat-gun to loosen it before scraping)... am I right in thinking that I should really remove the paint and paper before tiling? If possible I'd like to do all of the prep work myself before getting someone in to do the tiling, is there anything else I need to do before? Or can they mastic straight onto concrete? I've seen that people install a water proof boarding system such as wedi board, should I do this around all of the bathroom or just where the shower is going to go?

2. Do I need to worry about damp/moisture? Considering it's old style brick with lime mortar and the room will be a bathroom, is there any reason that it'd be better to take the concrete off the walls? Is wedi board on-top of concrete good or bad for any reason?

3. Should I use concrete to cover-up the rest of the brick in a similar way, would that make tiling easier? Just wondering what I use to even up the covering at the top in the pics.

4. Is there a sensible list/plan of things to do in a bathroom when building it from scratch (which I'm pretty much doing) anyone has a link to? I'm trying to work out if I put the VCL in before I put cabling in for electrics etc (shower and downlighting will be from ceiling).

Any help/pointers/general advice/things to consider would be really appreciated!

Cheers, Matt

Some pics of the room, walls and paint/paper covering the concrete:
www.matt-k.com/downloads/house/bathroom/20170917_151641.jpg
www.matt-k.com/downloads/house/bathroom/20170917_151542.jpg
www.matt-k.com/downloads/house/bathroom/20170917_151440.jpg
www.matt-k.com/downloads/house/bathroom/20170917_151429.jpg
www.matt-k.com/downloads/house/bathroom/20170917_151416.jpg
www.matt-k.com/downloads/house/bathroom/20170917_151415.jpg
www.matt-k.com/downloads/house/bathroom/20170917_151412.jpg
www.matt-k.com/downloads/house/bathroom/20170917_135840.jpg
www.matt-k.com/downloads/house/bathroom/20170917_135830.jpg
www.matt-k.com/downloads/house/bathroom/20170917_135824.jpg
www.matt-k.com/downloads/house/bathroom/20170917_135810.jpg










Sans Serif

 

[chappers]

pictures would be useful so we can see what condition the walls are in. Get the paint and paper off and then lets go from there

 

[Matt K]

Hi Chappers,

Sure, I've added some pics to my original post. DIYNot has a filesize limit so I've provided a link to them, you should be able to just click on the links.

Any help/advice really appreciated!

Cheers

 

[Adam182]

Im currently in a similar situation, I whipped the render off my walls and took it back to brick, literally took half hour if that with an SDS drill.

I have since battened the wall with 2x2 and I plan to insulate between then foam and foil tape the gaps.

The shower area will be Hardie backer and the rest MR plasterboard, all tanked to double down on water resistance. Final finish will be tiled wall to ceiling.

 

[Matt K]

Thanks for the info Adam182, I think yours is a pretty comprehensive approach. I may well need to repoint the brickwork if I take off the concrete render, but that might not actually be a bad thing as the masonry is a little loose in places! (Definitely needs sorting before I redo the floor which will be attached to the same wall albeit a little lower down).

Is there a way of doing what you're doing whilst saving some of the space (thinking the 2x2 plus the board, mastic and tiles is taking up a bit of width) in the room?

How did you make the Hardie backer matchup to the same level as the rest of the wall?

How did you double tank it? Part of what I'm doing is a big wetroom area at the one end of the room so very keen to understand a good approach to doing it.

Cheers for the info so far, Matt

 

[Adam182]

To save space you could just take the render off and then dot and dab straight onto the wall, this would save the space taken up by the 2x2. The reason behind the 2x2 for me was so I could get some insulation against the cold exterior wall, I could have however dot and dabbed insulated PB instead and not bothered with the battens this would have saved a few mm overall.

That's as far as I have got so far as its an ongoing project. The difference between the Hardie and the Plasterboard is only 0.5mm so that will be taken up with the tile adhesive.

Apologies for not being clear, I am not double tanking, ill just be tanking once but in theory as I'm using Hardie on the shower area and MR Plasterboard elsewhere + Tiled throughout I could get away with not tanking at all. The tanking will just be a second barrier of moisture resistance.

From what I've gathered on these forums as you are doing a wetroom it would definitely be beneficial if not essential to use both Hardie (or similar) and also tanking.