shower tray waste issue

[Jim K..]

Looking forward to the photos already ;-)

[ss]

I havent ordered tray yet. Ideally I want a 1200 x 800 tray. Unfortunately the waste connection would be directly above a joist. A longer 1300 tray all appear to have the waste in the middle of the tray and would need to attempt access to connect from the adjoining room so trying to avoid that. I am trying to achieve a sort of walk-in so a shorter tray I am trying to avoid.

Any thoughts on how to solve this I am reasonable at DIY, plumber will make connections though. See image.

[Fredxx]

I think you have to continue your hunt for one with the outflow in the right place? I would have thought a waste 1/2 way along the long dimension would be available from somewhere!

[Fredxx]

A cheap one?

There are others

[GB]

Is that sketch accurate? Not much overlap where the joists are joined. or is there a support underneath?

A very large tray with the drain in the middle is not a great idea. They can snap in the middle, because that is the thinnest point and that's also the most stressed point.

Mira do a 1400 x 800 with the waste at one end. Too long for you?

I thought you were going to raise everything up a bit, so does it matter where the joist is?

[ss]

yes I can get them but trying to avoid as the plumber would prefer to get the waste as near to the stack as possible and avoid going through several joists and at that point I will have laid the overboarding so the access to connect would have to be from the adjoining room.

[ss]

........I believe it maybe a support wall underneath, it is not to scale.

...........I will check that out.

..No, I wanted low profile and the plumber has had a look and can accommodate the waste a bit lower down in the stack. I think he is going to add an additional piece in to the waste stack but a bit lower than the current one.

[ss]

I dont want the waste half way along the length as that creates more issues.

[tabbypurr]

An option not yet mentioned is to add crosspieces between joists each side of the cut so the joist you cut gets supported by its neighbours.

NT

[Steve Walker]

When I put in our shower, there was a joist partly in the way. I used a shallow waste, with an elbow mounted straight onto it, dropping down the side of the joist and notched the joist (and the floorboard above from underneath to clear the elbow). The notch in the joist was only a few mm more than already used elsewhere by 3/4" pipes installed from new and the joist was no longer having to support a full bath, so a little loss of strength did not concern me.

SteveW

[ss]

Unfortunately this waste would be bang right in the middle of the joist so would need to take approx half the depth of the joist away.

I am now thinking about a narrow shelf (maybe 3 inches) at the opposite end to the waste pipe end so I could slide the tray down towards the waste by the required amount. I just wonder if I could seal the `shelf` properly to make it watertight.

[ss]

I will google that for further info, thanks Tabby..

[tabbypurr]

same method as used for loft floor openings

NT

[Tricky Dicky]

+1

Richard

[John Rumm]

The term usually used for these is "stringers"

[John Rumm]

So what solution are you looking for exactly?

(I have a catalogue here with hundreds of trays of all shapes and sizes, and quite a variety of water outlet positions, I can look for a (slightly) different size if you want?).

[ss]

The plumber is coming back out tomorrow to look at options for me, will see how that goes first.

[Clive Arthur]

Or, as you don't need to use the full depth of the joist, cut away what you need to, and use galvanised steel heavy duty restraint straps bolted either side of the joists at the bottom to strengthen what's left. Pre-drilled 5mm thick by 30mm wide seems commonly available.

Cheers

[Rob Morley]

You could custom make to your own requirements in concrete and/or GRP.

[tabbypurr]

You could. I wouldn't like to.

NT