Shower Tray Waste - Advice

[richo106]

Hi all

I am just sorting my bathroom wastes as they are being installed in the next couple of weeks.

 

I have an issue with my shower waste, due the depth of the waste it hits the top of the posi joist ( see attached pics)

 

I would to notch the posi joist out and batten it in between to strengthen it back up but I guessing this a big no no.

 

Is my only option the bring the shower tray forward in front of the other joist and then can you get some kind of set?

 

Any ideas or suggestions would be very welcomed as I am stuck abit on this

 

[richo106]

[Temp]

I guess you can't turn it 90 degrees because it isn't circular. The trap I mean not the tray.

 

Can you turn it 180 (so the outlet points the wrong way), then make 180 descending bend to get it lower and heading in the right direction? Use 2 large radius bends not sharp 90 degree.

 

https://www.screwfix.com/p/floplast-solvent-weld-bend-92-5-white-50mm/96439

Edited May 14, 2023 by Temp

[MikeSharp01]

How is the pozi fixed to the floor boarding, what it the pozi spacing and what else is the pozi supporting? I cannot help thinking that a structural engineer could show you how to reduce that top stronger out of the way. 

[richo106]

Thank you @temp and @MikeSharp01 definitely gave me a couple of options

 

@MikeSharp01 the joists are spaced at 400mm centres and not supporting anything else. The floorboards are nailed and glued. This would be preferable option if it’s doable. I will email my SE tomorrow, pretty sure he will say no but worth an ask!

[Conor]

See if you can get a linear waste from the same manufacturer that has an outlet on the end.

[MikeSharp01]

Perhaps as an idea offer SE to put a couple of shaped (SE to specify length) 18mm (SE to specify - might want thicker) Marine ply plates either side fixed, glue (SE to specify - might want structural adhesive) plus screw/nail/possibly bolted through  to both stringers and the end upright (SE might suggest shoulder blocks and other strengthening). The challenge will be to play out what happens at the end of the plates although wood does not have the stress point fracturing that steel, for instance, has SE will have a view AND the potential for buckling the ply plates as they deal with the compression stress in the top stringer that is no longer there, which I feel would be small but might not be. You may also be able to get some crosswise support from adjacent beams if you can get plates in. Either way it won't be a standard detail so in the SE's hands.

[richo106]

On 15/05/2023 at 05:39, Conor said:

See if you can get a linear waste from the same manufacturer that has an outlet on the end.

Unfortunately they don’t I have just spoken to them 

[Conor]

17 minutes ago, richo106 said:

Unfortunately they don’t I have just spoken to them 

You could adapt that one. Put a bung in the existing outlet, use a hole saw to cut a new outlet and use a 2" tank connector. Or as suggested, flip it 180⁰, use two 90⁰ bends to bring it back round.

[richo106]

29 minutes ago, Conor said:

You could adapt that one. Put a bung in the existing outlet, use a hole saw to cut a new outlet and use a 2" tank connector. Or as suggested, flip it 180⁰, use two 90⁰ bends to bring it back round.

Yes I will be picking up 2 90’s later in the week to have a look at 

[richo106]

Also the outlet on the waste is only 40mm, is it worth putting 50mm in to it or not? 

[TonyT]

100% worth going 50mm

 

its in the top ten of things to do right the first time to safe grief later 

[richo106]

2 hours ago, TonyT said:

100% worth going 50mm

 

its in the top ten of things to do right the first time to safe grief later 

Thank you

 

I think I am going to go the 2 x 90 route but worried about space so it might the 90’s might have to be in 40mm will that be an issue?

[Marvin]

4 hours ago, Conor said:

You could adapt that one. Put a bung in the existing outlet, use a hole saw to cut a new outlet and use a 2" tank connector. 

Now this is a man who has overcome every sort of building challenge!!!!

 

 

[Temp]

2 hours ago, richo106 said:

Thank you

 

I think I am going to go the 2 x 90 route but worried about space so it might the 90’s might have to be in 40mm will that be an issue?

 

This is what I had in mind above. The two 90 degree bends dont need to be vertical but can be rotated to preserve some of the fall for along the pipe if needed.

The bits aren't very expensive. I'd get both sizes and see it the 50mm will fit. Perhaps pick up some 45 degree as well in case this helps.

 

With solvent weld I test fit everything without adhesive then put alignment marks on all joints so I can assemble it in my hands rather than trying to do it in situ. A decent amount of adhesive  give you a bit more time before it sets up.