Hardiebacker onto terracotta hollow tile wall

[Waluigi]

Hi all,

I hadn’t heard of Orbrey before but if anyone who isn’t the sole supplier of the suggested product weigh in on this please? Would Hardiebacker work in the same way; dot and dab, with fixings into the mortar? Is Orbrey actually any better?

Two very different boards. Personally and completely irrelevant to the forum sponsor being on this thread, I’d still opt for Orbrey. It’s far easier to work with, to manoeuvre and to cut plus the actual board itself is waterproof so would only require tanking at the joints, screw holes and abutments. Hardiebacker is not waterproof, it requires fully tanking and despite what I have heard the reps say, it allows moisture to pass through it. Hardiebacker on a floor area is very good but on walls less so.

There are however some disadvantages with Orbrey and in fact all lightweight foam boards- they require a tighter spacing between timber studs on stud partition walls, mainly on boards 12mm. The thicker boards less so.

In terms of using Plasterboard, it’s absolutoey fine. I’ve been using it in wet areas for a very long time with either a paint on or sheet tanking membrane on top within wet areas. No need to tank in areas outside of the shower/bathing areas.

Just to add- bare plaster in a Bathroom is absolutely fine. Prime the wall with a primer or watered down paint.

 

[adibell]

Great, thanks for more replies. So with regards to using plasterboard, would I face difficulties if my tiles on their own are 20kg/m2? Why would anyone pay a fortune for tile backer boards over the MR plasterboard? Should I still use mechanical fixing with the MR plasterboards?

Additionally, because I hate the void behind plasterboard when using dot and dab, I taught myself to plaster, and use Hardwall plus skim. Would I be better just to use bonding (seeing as the clay tiles will be low suction?) and tank it, then tile onto that? For the plaster only areas, I won’t be dot-dabbing, so should I just brown the whole room? Should I also skim before tiling if that’s the case, or is the basecoat plaster ok to tile onto. I’ve gotten myself confused with so many options now!

 

[WetSaw]

Wedi board or similar foam cored boards are lighter and only need sealing on the seams and screws. Plasterboard is a lot cheaper!

 

[Waluigi]

Are you tiling the bare plaster walls? I assumed these were being painted.

I would always try to tile onto a board rather than plaster, With the exception of smaller, lighter tiles.

 

[adibell]

So I’m tiling up to a waistline all the way around the room, then full height above the shower bath, like the attached image (the bare painted plaster bit in white obviously).

So I’d have to plasterboard/tile backer board most of the room, but then I’ll do browning plaster for the bare plaster bit. I’ve looked at Fischer plugs and would be happy using these as mechanical fixings in the hollow clay bricks, now I just need to decide whether I use tile backer boards, or WR plasterboard...plasterboard is cheaper, but additionally, I lose 12.5mm+ dotdabs, which I can’t then actually fit between the ends of the bath and the end walls....the bath is 1700mm, and the opposing walls are 1720 apart!

 

[Waluigi]

The single only reason I would ever use MR plasterboard in a Bathroom is if I was using TE boards and filling the joints.

For all areas outside of the shower area I would tile directly on to bare standard plasterboard.

Keep in mind that if you do skim MR Board, you’d need to use Thistle bond it. MR board isn’t designed to be skimmed bare. It has a coating.

 

[adibell]

Using the MR plasterboard in the wet areas and tanking, would there be a difficulty tiling onto the surface of them because of the coating? Does a tanking system offer a good adhesion surface, or would I also want to use something like Gripcoat to give a mechanically grippy surface? Would I also potentially see an issue tiling onto the standard plasterboard with the weight of my tiles (20kg/m2)?

I feel like plasterboard is the best option cost-wise, I’m just concerned the bath won’t fit if I add 2x 12.5mm + the dabs at each end of the bath. But I guess I’ll find out when I strip the plaster off later today.

 

[Waluigi]

Get everything stripped out and see what you have.

The depth of a dot and dabbed plasterboard might be governed by how Plumb your wall is either side of the Bath.

As a general rule- tanking doesn’t reduce the weight you can hang off PB but each tanking products is different. You would never usually need to prep the tanking before tiling.

 

[adibell]

But would the surface coating that prevents you from skimming onto MR plasterboard also mean that your tiling adhesion isn’t great?

 

[Waluigi]

..... it’s absolutely fine to tile direct on to MR plasterboard.