Shower tray fix

[Dee]

I've read conflicting advice on bedding a tray onto cement or tile adhesive.....which should I trust. Its going onto 18mm ply, onto old joists

Thanks 

[Pocster]

28 minutes ago, Dee said:

I've read conflicting advice on bedding a tray onto cement or tile adhesive.....which should I trust. Its going onto 18mm ply, onto old joists

Thanks 

I used flexible tile adhesive. I would think that bit of flexibility would help . Assume it’s a solid e.g stone tray ?

[Pocster]

1 hour ago, Pocster said:

I used flexible tile adhesive. I would think that bit of flexibility would help . Assume it’s a solid e.g stone tray ?

I see you got a similar response in your other thread I.e use tile adhesive to bed the tray . Not sure what you are confused about …. ?

[Dee]

Hi, I've watched a number of YouTube threads about this question and one plumber spent 20 minutes extolling the virtues of sand and cement rather than adhesive. Some say one others say the other hence my confusion....or maybe its confidence. I have to get this right, I can't pay for a pro to do this so I'm reaching out to understand better before I try to do this myself. I'll re read the thread. Thanks for your input. It's a great forum 

[Pocster]

I’d say tile adhesive as it gives you more ‘play’ . A sand /cement mix will depend on your mix .

I think it’s one of those things where either method would work tbh . Understand you want to be confident before you commit !

[saveasteading]

Once it is plonked down, any prising up to get levels perfect would lift it away from sand and cement, but tile adhesive will cling and there won't be voids.

[joe90]

39 minutes ago, Pocster said:

I’d say tile adhesive as it gives you more ‘play’ . A sand /cement mix will depend on your mix .

I think it’s one of those things where either method would work tbh . Understand you want to be confident before you commit !

I agree, sand and cement is very solid and especially on any timber, which will move a little. It’s a bit why I don’t like mortared ridge tiles .

[Dee]

Thank chaps. I'll give with tile adhesive.

[Dee]

My next question....sorry.....is the waste pipe run.

The shower pipe will have to run parallel to the joist and T into the sink. Is this OK?

How much fall is dictated by the depth of the joists for both sink and shower to get under. I estimate total run from shower to sink to loo appropriately 4m.

The sink will run as per my sketch to the loo. Should I only use 90⁰ bends or can I use 45⁰ ? (The dotted line is an alternative route).

Thanks for your patience 

[saveasteading]

45° will always run more smoothly if you can. A pair of 45s will also allow more tweaking. It's probably more to do with your geometry.

90s are easier though.

[Pocster]

57 minutes ago, Dee said:

Thank chaps. I'll give with tile adhesive.

I’d make sure you have a rubber mallet and spirit level handy . Then you can gently tap it level … 👍

[Temp]

Check the instructions.

 

Some/most trays need support over the whole base area so for those tile adhesive and a notched trowel is what I used. Allows some levelling like you would a tile.

 

Other trays are strong enough that several large dabs of mortar can be used and that's slightly easier to level the tray.

Edited October 11, 2023 by Temp

[saveasteading]

1 minute ago, Temp said:

strong enough that several large dabs

But if the bottom is flat, then why not lay it as one big tile?

[Dee]

The tray has a solid base. 800 x 800 so not massive.

I've just  levelled the joists with noggins and now the ply is absolutely level, no rocking or anything.!

Do I now screw down the ply, add tile adhesive, set tray down and then put trap in?

I've got a McAlpine trap so should I use silicon on both rubber seals A,B and C or none??

The small pipe that comes out of the trap, is it just hand tightened onto the trap or some sort of glue used as once it's in its very tight accsess so I have one shot at it.

Thankyou for being so patient and helpful everyone!

[Pocster]

I personally would not use any silicone on the trap . It should work “ as is “ . Also if it needs to be removed later it will be far easier . Pipe off trap is just hand tighten yes - no glue .

[Pocster]

You got this @Dee .

What I did to boost my confidence is once the tray had set the next day I put some temp pipework off the trap into a bucket . Then gently tipped water into the trap from above . If no leaks it’s a good start ! 👍

[Temp]

9 hours ago, saveasteading said:

But if the bottom is flat, then why not lay it as one big tile?

 

Yes you can do that and groove the mortar with the point of a trowel. A totally flat solid layer of mortar can make it harder to level the tray.

[Dee]

HELP! The corner where the shower will sit isn't square! Which wall should I square it too??? It's out by 20mm bottom right! Average it out or square to the back wall? I plan on having just a door, so if you look at the sketch I did for the pipe run then the l will build the left wall off the back wall, (the back wall is stud work) and the right wall is brick.

 

As there is a void under the floor of about 20" should I put insulation down? The kitchen is below.

How tight should I screw the trap? baring in mind I don't have the same grip strength as a man? is it possible to over tighten the trap ect and knacker it?  Would you recommend PTFE tape on every thread joint as belt and brace?? Once the floor is down that's it!!

Edited October 12, 2023 by Dee