Clay drain hopper/ trap replacement

[geebs]

Hi everyone,

I’m trying to work out if this job is worth taking on myself or if I should get someone in.

I have a clay trap in my garage that feeds into the combined sewer. An extension was added by the previous owner but the drainage wasn’t changed. Now I have half a dozen things feeding into this trap and no drainage in the garden. It’s pretty shoddy, the guttering for the rear of the house feeds back inside to this trap.

I want to change this clay trap for a plastic hopper and extend the run 2m to allow me to tidy it all up and provide various other options.

I’m pretty capable at DIY and have an SDS drill with some chisels, so breaking up the floor isn’t an issue. How hard would replacing the trap be?

I need to figure out a way to be able to work on it and also keep things connected as much as possible to minimise disruption

I figure I’d dig out the trench for the new pipe first then tackle the trap last before connecting it all up and testing? is that the best way?

 

[Hugh Jaleak]

The hardest part would be connecting to the existing drain. Worse case scenario is the original Builders have encased the clay pipe in concrete, which makes cutting it and getting a connection somewhat more difficult, but not impossible. I'd (carefully) break out the surrounding concrete and expose the gulley and outgoing pipework to see what you have before doing any more.

If you can expose the outlet pipework, then simply cut through it with an angle grinder and stone disc, chamfer the edges, and use a Fernco type coupling to take you to 110mm plastic and you're away. New Bottle Gulley can be fitted to take existing wastes, and if you want to extend the pipework to take the rainwater, look for one with a Back Inlet.

 

[geebs]

Thanks Hugh!

I’ll start poking around to try to find the pipe work. Hopefully it’s not all encased!

 

[Hugh Jaleak]

Think you can see the outlet from the pot in one of the pics, if not feel around (with a stick or something), should be able to feel the outlet, that'll tell you which way it goes.

 

[geebs]

I had a look for the pipe today. Thankfully it’s not encased. It’s got a big shoulder on it that’s almost touching the concrete. Might be able to drill around the shoulder and remove the concrete without causing any damage.

hoping that I’ll be able to do this drainage work myself now

 

[Hugh Jaleak]

Remove as much of the concrete as you can/need to. You may find the gulley comes loose and is easily separated from the pipework at that joint, if not (and the joint was made properly), I'd carefully cut through the pipe just behind the collar. (Make sure pipework is supported before cutting in case the gulley is holding it up!) Once the gulley is disconnected, you can fit a coupling to the cut end, change to 110mm plastic and carry on from there.

 

[geebs]

Thanks Hugh.

I uncovered some more of it. I’ll pick up some bits from screwfix this week and I’ll be able to get going properly with this now.

lucky I’m replacing it because I think it’s got a leak at the mortar joint.

I’m planning on putting in a bottle trap for the sink etc, then another one at the end of the run that will be outside for the roof gutters. As this is a combined sewer run should put in a p-trap where I cut the pipe to stop any smells coming up?

 

[Hugh Jaleak]

If you're using a bottle gulley, then that includes an integral trap. Personally I'd use one of these, FloPlast D530 Back-Inlet Bottle Gully | Underground Pipe Fittings | Screwfix.com to replace the existing gulley, and accept the wastes. It would then allow you to run a section of 110mm pipe from the back inlet to take the gutter downpipe, removing the need for another trap. Centre section of the gulley also removes for easy cleaning/unblocking should the need ever arise.

Alternatively, you could put a junction in and have 2 gullies, but connected to a combined system, both would need to be trapped.

 

[geebs]

Had to delay the work until this week. But I’ve made some good progress. Managed to get a clay pipe cutter very cheaply on eBay but it was one link too short so I extended it on the fly and it cut the salt glazed pipe like a dream.

While digging out I encountered an unexpected water pipe that seems to span across the garage which has stolen an inch of depth, not sure why that pipe would be there because there is already a sink in the garage and it’s not connected to it. But don’t really want to mess with it if I can avoid it

 

[Hugh Jaleak]

Given the age of the property, that water pipe could have fed a former outside WC, tap or even a neighbouring property. If it's Lead, I'd leave well alone!

 

[geebs]

Haha, yeah the last thing I wanted to do was mess about it with that pipe! I managed to use a spare fernco adapter to reduce the fall slightly make up for it, there was plenty of room for manoeuvre.

Got a D530 bottle gully to fit and then I can move on to the land drain part when it’s a bit drier.

I’ve been looking around for a 4 way gully so I can have some mini french drains running along the back wall of my house but I can’t find anything suitable. I don’t think a 320mm dia 3 inlet inspection chamber will work as well, but if that’s the only option I’ll have to go that route

 

[Hugh Jaleak]

Have you looked at the Osma Bottle Gulley? They are more expensive, but it has 3 bosses that can be opened for connections. Might be what you need. OsmaDrain Bottle Gully 87.5° 110mm (closed bosses) 4D900 | Travis Perkins

 

[geebs]

Now that would be exactly what I’m after! Perfect!

 

[Ian H]

Have you looked at the Osma Bottle Gulley? They are more expensive, but it has 3 bosses that can be opened for connections. Might be what you need. OsmaDrain Bottle Gully 87.5° 110mm (closed bosses) 4D900 | Travis Perkins

The Rolls Royce of gullys

 

[JohnD]

I'm thrilled to see you have a clay gully that is not broken.