100 mm upstand under shower tray - pro/con

I did this in one shower where there simply wasnt enough underfloor space to run the drains...

Plumbing is easier

The step up cant be shuffled over. You may need to raise or ramp the local floor

If it's going to be used for infirm people in future make sure that the underside of the shower base is fully supported where a shower chair may be placed. A chair may/will load the base in 4 very small points of contact.

Also provision for grab rails that are firmly screwed into the walls or screwed in to something substantial behind a plasterboard/aquaboard/tile covering.

The suction cup grab rails were not recommended by the local social services when assessing my elderly mothers needs. They can fail when someone grabs them when falling.

The plan is to include grab rails at suitable points, and also a fold down wall mounted chair with legs. This will hopefully spread the load.

Now looking at 10 years out (or more, hopefully) but now seems the best time to get it all sorted.

Cheers

Dave R

The ones you mention. I would suggest using a fairly substantial shower tray i.e. one that doesn't flex when someone gets in. This will probably add another 100mm in height. If you have the space, depending on the type of entry, it might be worth adding an external step at half the total height.

If you mount it as you are supposed to on a bed of sand and cement, it wont flex.

This will

Suction cups for the soap dish, maybe, but for grab rails!?

even soap dishes fall off. I've just had to drill holes in daughter 1's tiled bathroom wall to hold up her soap dish.

In my experience the only reason for a step up into the shower is to enable the waste to run downhill. Often in older houses the soil pipe and the bathroom wastes exited through the outside wall above (or just on) floor level. Fine for a pan and a sink and a bath but a walk in shower requires a lower exit for the waste.

So if you can't be bothered to pull up the floors, cut through joists, possibly re-engineer the local structure a bit, maybe replaster the ceiling below, make a massive new hole in the outside wall, do the filthy job of altering pipework to the soil stack, probably while up a ladder and make everything good and tidy afterwards ... ... the idea of a little step up into the shower becomes very attractive.

TW

Plenty on sale on Amazon

Yes, IME it's common. In my last house it was only a very short run from the shower to the stack so I put the base at floor level because the risk of the waste pipe blocking was negligible ... but it's still a risk. If you do this then choose a shower base with the drain near the front so you can make an access in the floor if you have to change the trap.

I haven't used one (yet) but search for "shower waste pump" for an alternative approach. I've no idea how noisy they are.

That's introducing a risk of failure for very little reduction of work compared to fixing them securely. Safety equipment needs to be reliable.

When visiting friends a few months back they were trying to unblock the shower waste from a build up of hair and soap. What they didn't realise was the centre part was removable for cleaning. It did take the use of a pair of pointed nose pliers to remove the centre basket as it gave every impression that it hadn't been removed for many years prior to them renting the property.

Yes, I have one of those. Actually I find a small Allen key better to get the trap out, it can be pulled quite hard, pliers tend to slip off.

The waste goes by a separate pipe to a drain outside the back door, and I find most shower blockages are due to leaves and hair in the grid there.

I got away with reducing height required by omitting the trap: outlet, elbow (bend is better but needs more height), push fit to give a little flexibility, out through wall slope along the wall with HepVo valve. Same with basin and sink. Rigged all the pipework to hold the joints in place and enable access to valves. Any freezing will be due to crud in the valve - happend with basin, as toothpaste, saliva etc. do build up. No problem with bath as my (head) hair is short.

I went for no upstand. As I covered the rest of the bathroom floor with

The trap is designed to be cleanable from the top and should not require access from underneath - but if it ever does, I'll go through the ceiling below (hallway) and make good with a pre-made access hatch.

There is already internal waste plumbing under the floor from the bath to the internal soil stack in the same bathroom.

As far as I can see a bath waste isn't going to be massively higher than a shower waste, but a 100ml up stand might make this easier.

So - most of the pipework should be reusable, I hope.

Cheers

Dave R

Having just done the opposite - taken out a non-upstand shower with plumbing under the floor and replaced it with a bath - I'd suggest double checking the water traps, especially if tapping into a soil waste. I think the required depth of the water trap is 50mm.

My existing installation had nothing like that - just a shallow water tray type affair from the shower. And whoever installed it had properly hacked away at the joists and managed to assemble the most tortuous route fror the shower and basin wastes imaginable. It'd block frequently and didn't smell too good.

Coming back to this as we firm up the requirements.

I finally got to visualise what a 100 mm up-stand with a 30 mm shower tray on top would look like.

This is the same as two house bricks laid flat, one on top of each other.

I set this up on the deck and looked at it, and consulted, and this does not seem like a goer.

Better to be as flush as possible. Now wondering if we should go the other way and remove the floor boards and sit the shower tray on the joists to reduce the lip,

Cheers

Dave R

If at all possible, this is the way to go; the problem then becomes how to arrange a fall from the pipe to the sewage system.

Past the trap in general the pipe is going to be at the level of the shower base. You have the width of the ceiling joists to get the fall to the nearest outfall.