What is this item called - drainage

[Harry Bloomfield]

It is made from pot, its top sits level with the ground, it has a 5"x

5" plastic grid sat on top of it, a wash basin drain enters it somehow [1], but not via the plastic grid and it has a water trap, it then discharges into the drain. [1] The drain seems to enter along side the square part - all buried presently under concrete and I'm reluctant to start digging it out, until I can find a replacement. It was installed about 25 years ago, during a refurb.

The problem was that wet concrete got into it some years ago and set up partially blocking it. I am now looking to dig it up and replace it - if only I knew what it was called to search for a replacement.

[Andy Burns]

Gully trap, gully drain, or similar terms on a picture search should get you there ...

[Harry Bloomfield]

Brilliant, thanks!

[Adrian C]

One of these?

Hepworth Supersleve Housedrain P Trap Square Gully 100mm

[Harry Bloomfield]

Same sort of idea, apart from the lack of a separate entry for the wash basin drain. From what I can see by lifting the plastic cover, it seems to slope across towards the basin waste pipe, the deeper it goes down.

[Tim Lamb]

In message , Harry Bloomfield writes

er.. isn't this likely to be a *back inlet gulley*?

regards

>

[Andrew Gabriel]

I have a plastic one with an inlet for the bath. I think it's been used because if the bath drained into the top of it, there would be no fall on the pipe. This plastic one has a piece of plastic you can pull off which gets you to the other side of the gulley P-trap, for rodding, although I've never needed to try removing it.

[Harry Bloomfield]

Andrew Gabriel was thinking very hard :

This one is clay and there is no rodding access.

[Harry Bloomfield]

Tim Lamb formulated the question :

If you stand facing the house wall, the square plastic cover is on the left tight against the wall, the basin waste enters to the right of that square, with no obvious connection to the gulley.

If you remove the lid and look in, the left and right hand walls of the gulley slope in from top to bottom towards the waste pipe on the right.

The outlet obviously goes to a manhole which is behind you when facing the wall.

I may be able to get the SDS out tomorrow and dig down for a better look.

[Hugo Nebula]

Back inlet gully:

years ago, probably Hepworths. For some reason I can't post a URL, so google it yourself.

[John Rumm]

Its a "gully" - there are several different types depending on exact requirements.

[Stephen]

As other replies have said, it will be a gully. I don't think today's designs will necessarily look identical to your old one, but they will do the same job. I would think that plastic would be easier to work with than clay.

The gullies sold by Toolstation, like this:

have one outlet.

Screwfix sell back-inlet gullies, like this:

only a couple of pounds more. As you can see, the difference is that there is an extra 110mm connection on the back that can be used to connect your sink waste, for example.

However, it sounds as though the one you have is not a back-inlet gully and that the sink outlet joins the hopper, rather than lower down in the gully.

Like this:

difference being that the inlet on a back inlet gully is 110mm, whereas the inlet on this hopper will be 40mm.

If you bought the hopper, you could connect it to a trap, such as:

gully is just a hopper and trap all in one unit (AFAIK).

I had a blocked clay drain caused by some sort of cement setting in the bottom but I tapped the deposit with a piece of scrap wood. I was lucky that I was able to break the cement up without breaking the pipe. Then I removed the broken up pieces by hand. Perhaps you might be as lucky and would not need to change anything?

HTH Stephen.

[Stephen]

Is your bathroom on the ground floor?

[newshound]

Also, brick acid (hydrochloric acid) should dissolve cement or concrete slowly, without attacking glazed ceramic. But your geometry may not be favourable and you may need a lot of it.

[Harry Bloomfield]

Stephen brought next idea :

> Just have one outlet.

> The difference being that the inlet on a back inlet gully is 110mm,

or

> A gully is just a hopper and trap all in one unit (AFAIK).

All sorted now and thanks for the help and ideas.

Once I had dug down to it, it turned out to be a double gulley with a separate trap. They gulley was like a Y shape (two entries side by side), discharging into a separate trap. I only had to dig out the gulley part, which then gave me enough access to the much deeper trap. The mid part of the Y and the depth was restricting my access. I actually managed to clear out the what had once been concrete blocking the trap and all is flowing smoothly again.

I scooped out quarter of a bucket of gravel from the trap.

[Harry Bloomfield]

I tried brick acid several years ago, leaving it to soak unused for a month and it seemed not to shift it at the time. I think that after all it may have dissolved it, but left the trap still blocked with the aggregate. The depth of the trap and the gulley was such, that it made it not easy to properly check. I could only just touch the bottom with my finger tips.

An aqua-vac pushed into the trap sucked lots of gravel out, after which it ran free.