A question about bath drains

VoucherMan

Apologies for any bad descriptions. Hopefully it makes sense.

I've recently noticed a leak from the bath. On inspection of the plumbing, I found one of the joins had worked loose (where the grey pipe fits into the white)

3 images attached. The first shows the pipe coming out of the bath, into the trap, and then along a convoluted collection of elbow joints. The second shows the pipe where it goes below the floorboards, and the third, under the boards.

I'm puzzled as to why he would have done it like this. Also the pipe drops almost down to the plasterboard below, before rising back up where it's clipped on further along..

I could just repair the leaking connection and leave it, but I'd much prefer to have a 'decent' set of joints. 

The two simplest options, for ease of fitting, are either to slightly extend the downpipe from the bath, then connect the trap directly to the long drain pipe, or to use a bigger trap, such as https://www.screwfix.com/p/mcalpine-adjustable-inlet-tubular-p-trap-white-40mm/46577 , which I could then connect to the drain pipe. I intend to add a pipe clip or 2 to raise the pipe back to just below the floorboards.

My slight concern is that the McAlpine trap is not included in the bath section. I don't know if this is just missed by Screwfix, or if regulations mean it's unsuitable.

Before I start making a mistake I'll regret, I hoped someone knowledgable could suggest a suitable solution.

To have the existing trap connect to the long pipe, I'd need to extend the pipe down from the bath by about 6 inches. The McAlpine trap, assuming it's suitable, would hopefully have enough adjustment to fit without any additional joints.

BUFF

I imagine he did it that way because that is what he had in the van that did the job at lowest cost ...
Looks like the ideal place to use a flexible connector to me ...

Gavin83

There’s a lot wrong with that plumbing and the leak is just the start of the problems. Hoping a professional didn’t do that. Do you not get quite bad noise from the bath when running the taps?

Really the whole lot needs supporting. Waste pipes need to flow downhill and given how old this plumbing looks I’m surprised you haven’t had issues with the water pipes either.

Have you punched a hole through the ceiling below?

VoucherMan

Gavin83 said:

There’s a lot wrong with that plumbing and the leak is just the start of the problems. Hoping a professional didn’t do that. Do you not get quite bad noise from the bath when running the taps?

Really the whole lot needs supporting. Waste pipes need to flow downhill and given how old this plumbing looks I’m surprised you haven’t had issues with the water pipes either.

Have you punched a hole through the ceiling below?

Allegedly he was a professional. At least, he had a showroom locally. The closer I look at some of the 'out of sight' work, the more my doubts grow though.

 The 2 long pipes along side the drain only supply the wash basin, as far as I know. I've found an old photo from when the work was starting. One of the comments I remember making was to ask him to ensure the drain pipe was supported, as it sagged in the middle, especially when warm water was passing through. Now I see that rather than supporting the middle, he's just lowered the pipe at the plughole end. As for the elbow joints. He's just added to existing connectors instead of using new.

As for the ceiling below. Yes, when I first noticed the leak I thought it may be connected to the drain, and decided it would be easier to patch the kitchen ceiling rather than start trying to remove tiles from the side of the bath.  Unfortunately the water was coming from above floorboard level, so I had to start in the bathroom anyway.

BUFF said:

Looks like the ideal place to use a flexible connector to me ...

A useful suggestion, thanks. It almost makes the job look simple & idiot proof enough for me to happily tackle.

Section62

VoucherMan said:

Before I start making a mistake I'll regret, I hoped someone knowledgable could suggest a suitable solution.

To have the existing trap connect to the long pipe, I'd need to extend the pipe down from the bath by about 6 inches. The McAlpine trap, assuming it's suitable, would hopefully have enough adjustment to fit without any additional joints.

If there's enough clearance under the bath then my preference would be to run the waste pipe under the bath but above the floorboards, until it gets to the far end of the bath, and then drop down below floorboard level.

That way makes it easier to get a uniform fall along the near-horizontal run, and would give access for maintenance (and checking for leaks).  There's no sense putting pipes under floorboards under the bath if you don't need to.  They will be hidden by the bath side panel, so don't need hiding away under the floorboards.

The bath doesn't appear to be stood on bearers, so you could be lucky and have enough space to get the pipe through.

danrv

Section62 said:

If there's enough clearance under the bath then my preference would be to run the waste pipe under the bath but above the floorboards, until it gets to the far end of the bath, and then drop down below floorboard level.

That’s how I’ve done my bath installation.
Enough fall on the pipe using a low profile McAlpine trap.
Problem for the OP would be getting the waste pipe up above the floorboards with the bath in place.
Maybe the compromise would be a longer trap from Screwfix as shown. Then try and prop up the pipe enough under the boards for sufficient slope.

Section62

danrv said:

Section62 said:

If there's enough clearance under the bath then my preference would be to run the waste pipe under the bath but above the floorboards, until it gets to the far end of the bath, and then drop down below floorboard level.

That’s how I’ve done my bath installation.

Problem for the OP would be getting the waste pipe up above the floorboards with the bath in place.

Yours is almost exactly what I had in mind.

Personally I'd abandon the existing pipe where it is (having drained the water out) and just buy a new length of pipe... at about £3.50 to £4 for a 3m length it isn't worth the effort to extract the pipe for reuse.  The new pipe should be flexible enough to carefully bend it into the space, or failing that cut into two shorter lengths and use a coupler.

VoucherMan

danrv said:

Section62 said:

If there's enough clearance under the bath then my preference would be to run the waste pipe under the bath but above the floorboards, until it gets to the far end of the bath, and then drop down below floorboard level.

Problem for the OP would be getting the waste pipe up above the floorboards with the bath in place.
Maybe the compromise would be a longer trap from Screwfix as shown. Then try and prop up the pipe enough under the boards for sufficient slope.

This pipe is going to cause problems! You can just about see most of the pipe in the photo on the OP, and it's clipped horizontally as far as I can see, which from the bath plug to the end wall is about 8 feet with no drop! My hope is that as the water has managed to drain, albeit slowly, with the slight uphill slope, it will be a lot better once I clip the rest of the pipe up.

The problem for me with any pipework is access. I'm reluctant to try and remove any more tiles from the side of the bath unless I need to, and equally hesitant about any further destruction of the kitchen ceiling. The latter would certainly give better access to the pipe.

For now I think I'll get one of the flexible connectors BUFF suggested. It should hopefully be a simple fit. Then I can decide if I'm happy to live with it, or try some of the other ideas.

Section62

VoucherMan said:

The problem for me with any pipework is access. I'm reluctant to try and remove any more tiles from the side of the bath unless I need to, and equally hesitant about any further destruction of the kitchen ceiling. The latter would certainly give better access to the pipe.

I would bite the bullet and remove the side panel, aiming to replace it with a panel which can be removed (by undoing a few screws) for future maintenance.  Being in a situation where you need to make holes in the the kitchen ceiling to be able to do a basic maintenance task is poor practice.

Do the job properly, and do it once.

BTW, to answer one of your earlier questions, the type of McAlpine trap linked to wouldn't normally be used for a bath because of restricted space, but also because the volume of water in the bend is larger, and harder to drain out for maintenance, hence there being a higher risk of spillage.  A shallow bath trap contains less water, and typically can be almost completely drained before removing it from the waste pipe.  A deeper trap like the linked one used on a sink or urinal will usually have more space underneath to place a container to catch spills.

danrv

The waste pipe should have fall all the way to the soil stack but not sure if that’s the case here. 
My bathroom was badly done with horizontal or upward sloping waste pipes. Would be worth trying to get at the end of the eight ft pipe to modify it.
Bearing in mind that there may be a sludge build up in the pipe.

Connect an angle adapter and have the pipe protruding up through the floorboard.
Fit a new length as suggested above the floor.
I used solvent weld connections when I did mine.

Bendy_House

VoucherMan said:

 I've found an old photo from when the work was starting. One of the comments I remember making was to ask him to ensure the drain pipe was supported, as it sagged in the middle, especially when warm water was passing through.

Is that the original photo?

Apart from looking as tho' it's sagging (presumably under the unsupported weight of the long pipe), that's what I was going to suggest, along with adding a few supports along the pipe itself. But S62's idea is far better, and nicely modelled by Dan; that should guarantee the required continuous fall, make it far easier to add these supports, and keep it all nicely visible for checking apart from the far end, but that should be a simple double-elbow arrangement.

The double-elbow cranked bit might be best done with solvent-weld fittings, with a compression just where it joins whatever is at the far end. The whole caboodle can then still be removed afterwards if ever needed, in one piece.