Workshop
Ask a question

The Bunnings Workshop community can help with your home improvement projects.

How to build a waterproof false wall and shelf behind toilet?

richard-sydney
Getting Established

How to build a waterproof false wall and shelf behind toilet?

Hello helpful folks!

We are replacing an existing toilet with a Caroma Profile 5 with integrated washbasin.

The existing outlet position means the Caroma will have to be 40mm out from the existing wall.

So I'd like to support it with a 40mm deep false wall, about as high as the toilet, topped with a narrow shelf level with the washbasin.

 

Because of the washbasin, everything will have to be waterproof.

I'm thinking of wet area VJ board, but not committed to that idea.

I imagine it looking a bit like this project.

 

The dimensions are 40 deep, 900 wide, ~935 high (the approximate height of the toilet).

 

Any suggestions? :smile:

 

EricL
Bunnings Team Member
Bunnings Team Member

Re: How to build a waterproof false wall and shelf behind toilet?

Hello @richard-sydney 

 

Thanks for sharing your question about building a false wall behind your toilet. Using a false wall to keep the basin offset from the wall is an excellent idea. To keep everything as waterproof as much as possible, I suggest using Wall Tiles to cover the entire front of the false wall including the top and perhaps a small splashback to keep everything tidy.

 

For example, if you were to use a 450mm x 450mm tile you would need 4pcs and a bit to matchup with the height of the toilet. The top can then be covered with tiles along with the splashback. It does not have to be very high perhaps 150mm just to prevent splashes from going onto the painted wall of the bathroom. In theory you would need six tiles to cover that false wall. If done correctly and in coordination with the bathroom colour and flooring it will look fantastic!

 

However, if you are keen on using EasyVJ panels, I would still recommend using tiles for the top surface of the false wall. In this manner, even if it gets wet it will provide a very good barrier against the water. Just keep in mind that using bigger tiles means that there will be less grout lines.  

 

Let me call on our experienced members @redbournreno @Peggers and @prettyliving for their recommendations.

 

If you have any other questions we can help with, please let us know.

 

Eric

 

See something interesting? Give it the thumbs up!
MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: How to build a waterproof false wall and shelf behind toilet?

Hi @richard-sydney,

 

I thought I'd add a little more info on how you could create the false wall. If you were to use 66 x 30mm 2.4m F7 H3 Treated Pine Primed LOSP for the frame as per my rendering below and 9mm VJ panelling, that would bring you to 39mm, which should be about perfect for your needs. 

 

Since this isn't an actual wall of the bathroom, I don't believe it falls under the requirements of needing to be waterproofed. However, it would be in your best interests to use waterproof materials for longevity's sake. You can attach the treated framing timber to the existing wall and then clad over it with your wet area panel. Any screw fixings will need to be filled over, and then the panel primed and painted.

 

If you wanted to keep the project similar to your inspiration then a timber top could be added; just make sure to coat it well with a product similar to Cabot's Cabothane.

 

Please let me know if you have any questions.

 

Mitchell

 

 Wall.png

See something interesting? Give it the thumbs up!

Re: How to build a waterproof false wall and shelf behind toilet?

Wow that is a super detailed answer!  Love the diagram.

I'll see if I can get that 30mm timber, though I note it's a special order only now.  "no longer available to buy online or in-store"

 

We are actually getting a tiler to do the floor while the toilet is out, and will have a few tiles left over.

So I guess tiling the false wall is an option.

What material is best for tiling over in a wet area?  No point using VJ board as it won't be visible.

 

Thanks again all!

 

Re: How to build a waterproof false wall and shelf behind toilet?

Hi @richard-sydney,

 

If you could work with a 45mm offset from the wall, you could use 70 x 35mm timber

 

Tiling certainly is an option, as per @EricL's advice. My suggestion of using the VJ panel was only if you were to leave it exposed as per your inspiration project. For tiling purposes, you'd just use Villaboard, which is 6mm thick. That would work out well with the 35mm thick frame.

 

Mitchell

 

See something interesting? Give it the thumbs up!

Re: How to build a waterproof false wall and shelf behind toilet?

Hi folks,

Just to follow up on this - the project has been complete for a while now.

 

Here are the "before" photos of the original "outdoor dunny" which was likely original with the house.  The painted brick walls and concrete floor are in less than stellar condition.

 

20231018_105559 Large.jpeg20231018_105717 Large.jpeg

 

Here are the "after" photos.  When the old toilet was removed we sat the new one in position "freestanding", and I realised that a small gap behind the cistern is really not noticeable in practice.  In the end I decided to tile up the existing wall without building a false wall, and I'm glad of the effort saved.  I also decided we could afford to use a straight collar rather than a 40mm offset collar, to avoid any risk of blockage.  The result is that the cistern is about 45mm off the tiles, supported behind by 2 timber battens attached to the underside of the shelf.

 

The shelf is 90mm wide, I made a notch in it using my favourite woodworking tool (100mm grinding disc) which exactly matches the curves of the basin, then painted white and 3 coats of Cabothane as per @MitchellMc's advice.  The shelf is perfectly level with the rim of the basin, so bottles etc are stable, and it simply lifts off if we ever need to get inside the cistern.

 

We got professionals for the tiling and plumbing, but did all the painting, prep, fixtures and decorating ourselves.  We're really pleased with the result, and it's brilliant being able to handwash in the same room.  My only gripe is that, now the spiders and cobwebs are gone, I've had to start sharing this room with other family members!

 

20231204_095556 Large.jpeg20231204_095635 Large.jpeg20231204_095803 Large.jpeg

Akanksha
Retired Team Member
Retired Team Member

Re: How to build a waterproof false wall and shelf behind toilet?

Wow, that transformation is stunning, @richard-sydney! You've done an absolutely terrific job on transforming your toilet. 

 

Many thanks for sharing those updates. I'm sure our members will find your project inspiring. 

 

Look forward to seeing what you tackle next.

 

Akanksha

 

See something interesting? Give it the thumbs up!

Why join the Bunnings Workshop community?

Workshop is a friendly place to learn, get ideas and find inspiration for your home improvement projects