Shower waste...

laurel7172

I've bought a new shower tray without a waste included.

The first few that came up when I googled were described as 90mm wastes. What's the 90mm measuring, exactly? The diameter of the drainage hole, the clearance underneath??? What do I need to measure to buy the right one, please?

Also, the upstands for this tray cost £40. I built that into my bid (ebay), so I expect to have to buy them, but how feasible would it be to re-use the upstands from the old one? They're both 700mm square alcove trays-the original a 20 yo Armitage Shanks acrylic, the new one a Merlin Merlyte. Thanks!

eco-friendly_2

90mm is the depth of the trap. 40mm (1 1/4") is the size of the waste outlet on your tray. You must follow the manufacturers instructions when installing a shower tray or your warranty will be invalid. I would install the complete kit.

laurel7172

Thank you. That makes sense. It's only new to me, though, so no warranty to invalidate.

andrew-b

I disagree with you eco-friendly..90mm normally refers to the size of the hole ...90mm for a "high flow" trap. I have a 90mm diameter trap on my shower tray..usually found on shallower trays (ours is a 25mm high tray) where wastewater needs to be removed at a higher rate. 40mm is the size of the outlet from the trap and the size of the waste pipe itself. Other relevant dimension is the "depth of seal" which is basically the height of standing water in the trap (i.e. bottom of trap to bottom of outlet from trap).

Mine is the second one down here

eco-friendly_2

andrew-b

I'm not a plumber so I'm quite happy to be corrected I believed the ebay link that I put up would have suited laurel.

laurel would you put up a link for your tray.

andrew-b

i'm not a plumber either but DIYed our bathroom and had very limiting criteria on the shower trap dimensions. The usual sizes are 50mm and 90mm diameter. Very rarely are the depths quoted...much to my annoyance at the time!