Shower Plinth

[DazJWood]

I am about to build a shower plinth for my quadrant shower. I have WBP 18mm ply for the top surface and have bought 4 by 2 interior construction wood for the supports. I have a number of questions that I'm stuck on:

1) Should I treat either variety of wood before I put my shower tray on top? And if so what with?

2) I have a stone resin tray. I see that there are differing methods for fixing the tray to a ply surface. Some say sand and cement others say silicone sealant. Is this just personal preference or is one solution more robust than another?

3) Also, I have currently not got any backer board up for the partition wall as yet, (where the tray will go up against). Should I put the backer board up and butt the tray and plinth up against this or would it be better to fit the shower base and plinth up to the beams of the partition wall and fit the back board so it overlaps the rim of the tray?

Thanks in advance,

Daz

 

[Rico99]

Hi there,

1) Seal bottom and edges of ply.

2) Follow the MI's at very least use powdered floor tile addy.

3) Fit boards, then tray, seal round with silicon, fit tiles seal round again.

Rico

 

[DazJWood]

Thanks for the reply but to clarify:

1) Seal bottom and edges of ply.

With what? (PVA, wood and tile adhesive don't go together generally)

2) Follow the MI's at very least use powdered floor tile addy.

What's an MI? Is tile adhesive really the most ideal to use to attach and bed a shower tray down on to plywood?

3) Fit boards, then tray, seal round with silicon, fit tiles seal round again.

Is it best to screw down the plinth to the floor and also fix in the tray edges to the wall with silicone or something too?

Thanks,

Daz

 

[Rico99]

Hi there,

1) Something more like BAL SBR

2) MI= Manufactures Instructions

3) Screw legs to floor, screw plinth to legs, yes silicon seal round the edges of the tray prior to tiling, and then again after tiling.

Rico

 

[DazJWood]

As an update to this post (back in January). I am slowly progressing, but got side tracked on a couple of other jobs!

I have built my plinth now. The 18mm plywood that I am using for the plinth I have secured off a friend. It was previously used as a custom built internal door in a business unit. The wood itself is in good condition but has a layer of white paint on it.

The shower tray I am using states to fix the base down on to the ply with a cement mix. This probably is a daft question I'm sure, but do I need to remove the paint (sand it back) and treat it again (with SBR or PVA) or is it fine to just put the cement on top as it is (and then the shower tray). I guess what I'm asking is whether the paint on the ply will interfere in any way with the adherence of the cement to the painted board.

Thanks in advance,

Daz

 

[DazJWood]

Anyone?

 

[seco services]

i would remove it.

 

[DazJWood]

Why?

 

[Richard C]

How do you know your 2nd hand lump of ply is WBP? If it isn’t, it won’t like having wet mortar dumped on top of it! If your intent on recycling the door, I would be inclined to take the paint off but, personally, I wouldn’t use it. I think it’s a false economy to use 2nd hand materials in such a critical location; you may save 15-20 quid but if it goes wrong, it’s going to cost you far more than that to put right.

Assuming it’s a stone resin tray, the weak mix mortar is used to provide a fully supported base rather than stick the try to the floor; no need to prime with anything.

 

[DazJWood]

Thanks for the reply.

I have an amount of Hardie Cement Backer board (6mm floor backer board). Would using this over the top of the ply be a better idea? Then the mortar mix would be in contact with this only.

Thanks,

Daz

 

[Richard C]

Already said what I would do .
I don’t see the point of using the Hardibacker over ply, too many layers & that stuff is even more expensive than WBP! What do you currently have as a floor, bare joists or are you laying the ply over an existing flooring of some sort? If so what is it? You should be OK to sit the tray directly onto the Hardibacker if it’s supported by an existing floor but I’ve never personally done it like that & I would advise you check Hardibacker suitability further unless Tictic, Lance or any of the other tillers care to comment

 

[DazJWood]

The ply isn't going over the floor. It's for the top of the plinth as described in the first post.

I have built the plinth using 4 by 2 battens and then was going to use the ply over the top.

If the recommendation is to use new ply then I'll have to go and bite the bullet and spend another £20 and get some more. As you say for the cost it's not worth getting it wrong and having to rectify it afterwards.

Thanks,

Daz

 

[Richard C]

The ply isn't going over the floor. It's for the top of the plinth as described in the first post.

So it’s a raised plinth off the floor; sorry for my total ignorance but that wasn’t immediately obvious to me from your 1st post

I have built the plinth using 4 by 2 battens and then was going to use the ply over the top.

Fine; if you'd mentioned that in your 1st post it would have been obvious!

If the recommendation is to use new ply then I'll have to go and bite the bullet and spend another £20 and get some more. As you say for the cost it's not worth getting it wrong and having to rectify it afterwards.

IMO it’s not worth the risk & for 20 quid you can get a full 8 x 4 sheet of 18mm WBP. Consider it’s still F/A cost in the scheme of things if it goes wrong; you need to get your priorities right my friend

 

[DazJWood]

The ply isn't going over the floor. It's for the top of the plinth as described in the first post.

So it’s a raised plinth off the floor; sorry for my total ignorance but that wasn’t immediately obvious to me from your 1st post

I'm not sure how I could have described it better but yes it's a raised plinth.

I have built the plinth using 4 by 2 battens and then was going to use the ply over the top.

Fine; if you'd mentioned that in your 1st post it would have been obvious!

Erm it should have been obvious because I did mention it in my first post:

I am about to build a shower plinth for my quadrant shower. I have WBP 18mm ply for the top surface and have bought 4 by 2 interior construction wood for the supports.

If the recommendation is to use new ply then I'll have to go and bite the bullet and spend another £20 and get some more. As you say for the cost it's not worth getting it wrong and having to rectify it afterwards.

IMO it’s not worth the risk & for 20 quid you can get a full 8 x 4 sheet of 18mm WBP. Consider it’s still F/A cost in the scheme of things if it goes wrong; you need to get your priorities right my friend

Thanks for the advice I will purchase a new sheet and go from there.

 

[Richard C]

Thanks I'll remember that next time