3 Inch Clay Pipe to 110mm underground Drainage and Other Qs

[GoodDIYjob]

Thanks - more options - feel confident based on all the response it can be joined.

Did a bit more today, chipped a decent section of concrete off the clay pipe ready the cut. There were more cracks, I had to get past and not sure if I did that or that's why the 3" of concrete is on top of it...

Bought a floplast bottle gully and cleared out space below the downpipe beside house wall. I cleared down as far as I could, to what I believe is footings 300mm below dampproof course. But bottle gully much too high sitting well above DPC.

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• GoodDIYjob
• 1 Sep 2014
• 1

Thinking now the low back p trap and being able to adjust upstand height, as Ree suggested, is probably the go.

 

[GoodDIYjob]

Ok. Seems that flexseal ac4000 is actually for 4" internal dia clay pipe and dc115 just about works but is just a fraction sloppy on this 98mm od clay. May have worked... The best match I could find was Ac1221 which is only supposed to go to 95mm but slid over 98mm ok. Just thought I'd clarify in case others read posts in future.

Anyone needs a ac4000 or dc115 I have them spare now!!

Have mocked up the pipe run and gully trap - see attached.

I can't get the low back p trap any lower as the back feet are on the house footings and only about 300mm down.

This dismissed the bottle gully and also the rain interceptor with the low back p trap which seemed a good idea to stop splash as pipe could have gone straight in. See photo 1.

Advice please.

1) if I got a 15 or 30 degree angle socket connector to fit to the p trap outlet and then into the 90degree adjustable would that step down the pipe 1.5" or so, as it could do with sitting lower in the ground. It's all very close to surface at the start and the adjustment knurls on the 90 adj bend stick up even further??

2) any opinion on how far to space gully grid out from porch and rear wall?

3) I was thinking of seeing if I could find a specific shoe or otherwise just use the angled plastic connector as I've used in the mock up recycled from what was originally there and angle out at either 90 from wall or maybe 45 to avoid porch bricks as well. The top layer of porch bricks seems to half straddle the dpc line.

Won't mention where our elec supply turned up. Let's just say very, very proximate to the clay pipe and the grinder I used the cut through the clay ware.

As you can see even with the grid and low back p trap I'm not going to get 150mm below dpc but I'll monitor and I guess install flashing if it soaks.

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• GoodDIYjob
• 3 Sep 2014
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• GoodDIYjob
• 3 Sep 2014
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• GoodDIYjob
• 3 Sep 2014
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• GoodDIYjob
• 3 Sep 2014
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• GoodDIYjob
• 3 Sep 2014
• 1

Thanks v much

 

[Hugh Jaleak]

Builder often laid the drains on a raft of concrete, then haunched over with yet more concrete in that era, nothing unusual, just a complete PITA when you want to alter the drains 100 years on...... (When the run was complete the drainage inspector used to roll a ball through. If it came out the far end the run was passed!)

As to your questions: 1. I'd even look at a 45 ° bend to get that pipe as deep as possible as quickly as possible. I would also haunch some concrete around the base of the P trap/gulley to hold it in position, and also haunch over the shallow pipework for protection.

2. Gulley can be set tight against the house wall, although maybe wise to set a slate behind at against the house wall to act as a DPC.

3. Use a shoe or bend as required on the bottom of the downpipe, I'd also look at fitting a gulley surround to finish the job off and prevent gravel from the driveway been kicked/swept into the gulley.

 

[GoodDIYjob]

Thanks Hugh. Appreciate the specific advice.

I got a 30 degree and the main run is now bottomed out so think that is as good as it gets with further excavation. And that wouldn't work either due to the elec and gas supply lines running along either side!

I have set the trap in with concrete. haven't done slate but think I could do retro if it seems to get wet. The Grid and holder pull out completely so you can get pretty good access against the wall.

Gully surround sounds like a good finish idea. Where would I get such a thing or or you just mean bed some bricks or concrete edging....

 

[Hugh Jaleak]

A gulley surround is a 3 sided concrete edging, examples here: http://www.builderdepot.co.uk/9-x-9-concrete-gulley-surround-230mm-x-230mm.html Any good builders merchants should have various sizes available.

Choose appropriate size to fit your gulley, bed on and haunch it into place with concrete, then bench (make good) the internal space between surround and edge of gulley with a strong, (2-3 parts sand to 1 part cement), semi dry, mortar mix.

 

[GoodDIYjob]

It's finished.

Tried 3 merchants but none seemed to carry anything other than a 9" square gully surround here in guildford.

So I improvised and cut the end of the edging I had removed and used that to blank off the bed from the gully. Should help contain levels lower against side of house too.

Thanks for the help on here.

Photos below.

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• GoodDIYjob
• 6 Sep 2014
• 1

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• GoodDIYjob
• 6 Sep 2014
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• GoodDIYjob
• 6 Sep 2014
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• GoodDIYjob
• 6 Sep 2014
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[Hugh Jaleak]

Good job done. It's nice when people show the result of their efforts too.