Why would anyone build their own shower riser?

[Stefan]

I need to raise my shower tray (800mm quad) by ~160mm. The tray instructions recommend either building a riser from 2x4 and bedding in cement on marine ply, or using an easy-plumb riser kit.

The riser kit is about £50. It's only 100mm high, so I'd need to add some height with 2x4, but that's simple. I'd then need to replace the PVC sides with some standard sofit.

Building a platform from 2x4 (1 on edge, 1 on side to give 150mm) and marine ply seems straightforward, but the cost of the marine ply is prohibitive - £78 (non-trade) for a sheet of ply.

So it seems to be a simple choice - the riser kit is cheaper and less effort. But lots of people recommend building your own...it seems so obvious that I'm worried I must have missed something!?

What do the pros do?

Thanks!

[Brinkley]

i think you might be getting ripped off on the ply

[Ceramico tiling]

off cutt 18mm ply £5

[pjc]

Why ply?
Is it titanic ?
Is it going to float ?

[Stefan]

i think you might be getting ripped off on the ply

Could well be...TP price for an 8' x 4' sheet, only size they do. Internet search suggests I could get it a bit cheaper, but probably not a 1/3 of the price, which is what it needs to be...

off cutt 18mm ply £5

Fair enough, I'll look out for one.

Why ply?
Is it titanic ?
Is it going to float ?

I'm hoping my plumbing isn't that bad, so no to the floating. But the manufacturer recommends marine ply, and after the damage done by the leaking of the last shower (new build plumbing ), I'm taking no chances!

So it seems the conclusion from the pros is - don't worry about the manufacturer's instructions, and/or get ply cheap if you know where to look!

[Bri]

I was in Wickes the other day and even their exterior grade ply is only £24 per sheet

[timeless john]

I'd consider using Wedi board or similar - smaller sheets available, fully waterpoof and easy to fix/seal.

[Stefan]

Been doing some more digging, it seems that actual marine ply is overkill, and what I really need is something like WBP. Seems like there's a lot of confusion over what marine ply is, i.e. people referring to WBP and other plys as "marine"...certainly confused me!.

So will look again at this option - it's more work, but it feels like it will result in a more stable tray in the end.

Thanks all!

[Mike]

why do you have to raise it? for the trap? can you not sink the trap below the floor boards?

[easyt]

Is it on a solid floor? 160mm seems a big step with the shower lip as well.
I raised a base for mine using thermalite blocks on the concrete floor and screwed ply down on top.

[Riker007]

Well it is pointless in getting the riser kit if it only lets you get 100mm in height, then you have to add another 60mm for the remainder. You may as well ditch the riser kit (assuming you don't need the front panel that comes with it), and just build a platform from scratch, it isn't hard, just get it level, thats very important.
Sand the bottom off the shower tray (I assume cast stone or similar) to remove any bumps of cement from manufacture, there almost always is some bump or other. A bump of course is a no no, any bump or grit or whatever under your tray could cause a weakness.
You don't want to raise the legs right to the point of being on their last bit of thread, that isn't clever either considering the weight going on top. Even if you did get the riser kit, a few plastic legs is not enough support, so you would need to add wooden supports underneath the fixing board as well, so the purpose of the leg kit though a little handy in terms of levelling, still needs almost as much work as without it.

The fixing board you are going to put the tray on, its debatable which wood to use, there is no right or wrong answer. It should be at least 20mm thick (upto maybe 25mm if you wish) and cover right up to the edges of tray underside, not just the main tray area, but all the side bits too. If the tray is sealed properly, then the wood underneath should not get wet at all, so marine ply or similar isn't needed. The choice is yours, (not mdf) and if you are worried about dampness, which there shouldn't be in that area, you could varnish or paint it to protect it.

Cementing trays is very old hat, and can go wrong very easily, and crack up in time. As long as tray is dead level, in all directions when placed down on the fixing board, then expandable foam is preferable as this will fill any little gaps (usually a few minor ones somewhere). Or you can buy cement fixing compound, which is basically the same as gripfill but it is manufactured with this task in mind.

Plumber

[pjc]

Could well be...TP price for an 8' x 4' sheet, only size they do. Internet search suggests I could get it a bit cheaper, but probably not a 1/3 of the price, which is what it needs to be...



Fair enough, I'll look out for one.



I'm hoping my plumbing isn't that bad, so no to the floating. But the manufacturer recommends marine ply, and after the damage done by the leaking of the last shower (new build plumbing ), I'm taking no chances!

So it seems the conclusion from the pros is - don't worry about the manufacturer's instructions, and/or get ply cheap if you know where to look!

lol if it leaks you have a problem dont mater if its ply or porridge make sure it dont leak then you can use porridge insted of ply