Salt Glazed Sewer Pipes

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I've just excavated around the existing manhole, which is to eventually be moved, in my garden and have found it to be salt glazed socketed pipe work. I have measured the outer diameter of the pipes, which is difficult enough to get accurate, and have measured it to 200mm or so.

My question is, what would you guys suggest would be the imperial sizing of this pipe? 6" or 8"? Do they work with inner or outer diameter? When I replace the pipe I'll be using vitrified clay I think. So the next question is what would be the current sizing I would need to replace the existing pipe?

edit : To add, the pipe work is almost certainly thick wall.
 
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What waste is the pipe carrying is it just from your house or shared with other properties
 
It's shared.

edit : Was in a rush so here is some more info.

I got consent a while back for build over and moving the inspection chamber about 1m from its current position, in line with the existing main shared run. The pipe is 200mm or so OD and is salt glaze clay. I need to add a new piece of pipe in that needs to be clay too.

My concern is what size pipe do I use to connect to the old stuff after cutting it. I have a question about the inspection chamber too but I'm in a rush at work.
 
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Need the same size internal diameter, (under no circumstances reduce the size of the pipe!) Drainage starts at 4" (100mm), then goes 6" (150mm), 9" (225mm), 12" (300mm), 15" (375mm), 18" (450mm), 21" (525mm), 24" (600mm), and so on.

200mm external diameter salt glazed is going to be a 6" pipe. You'll need a couple of appropriately sized 'Fernco' couplers to join it to a section of 'Supersleve'. Chamfer all cut ends before joining.
 
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The internal diameter of the pipe (look inside any access chambers) will confirm the size, although it sounds likely that you have (expensive) 150mm sewers.
Fernco in particular make the best rubber jubilee fastened type adaptors unlike some of the universal adaptors that end up a little bit baggy and allow some annoying distortion of the union.

We often 'bite the bullet' in these situations and go all out, armed with a digger, plastic pre-formed manhole chamber bottom - risers - lid and frame, Fernco connectors, an angle grinder and a period of time that is not during the early morning bums rush hour! It is a lot simpler these days to graft in a new chamber than it ever was in the bad ole days of brick chambers and clay channels etc.
 
It is a lot simpler these days to graft in a new chamber than it ever was in the bad ole days of brick chambers and clay channels etc.

Glad you mentioned that. The build over was only agreed to after I accepted using brick or concrete. That could have been because the designer who submitted the drawings specced a 1200 x 750 monster for some reason. The existing IC is around 650 x 450.

I was going to seek advice about doing that kind of installation.
 
If you're working to a build over agreement you may be held to ransom on the spec. If that's what the Water Co want, that's what they must have. If you're looking at a chamber of that size, you'll need mechanical lifting to get the sections off the lorry and into the excavation.

Does seem rather large, how deep is the sewer?
 
1.1m to invert. The designer has screwed up I think.

I've emailed the water company to discuss the situation. Hoping to get them to agree to a change, even if I have to pay extra to get it amended.

The building regs specify that plastic is good enough. I understand I need one that will comply with the regs for adoptable sewers too so hopefully they'll play ball once they realise the plans are inaccurate and it's an inspection chamber not a manhole. I may even have to resubmit completely.
 
Last time we moved a 6" inspection chamber, which was probably 10 years ago mind we used all plastic and BC signed it off.
 
Edit! Larger diameter plastic chambers are available, if they will allow these to be used. The domestic 450mm diameter chambers are only suitable to depths of 900mm maximum I think.

Issue arises with getting rods or a larger diameter jetting hose into the pipe if the chamber is deep and narrow. The 3/4" jetting hose on a combination jetting unit doesn't bend that easily!
 
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JD and Wavin produce 600mm plastic chambers that are suitable for adoptable sewers to give a wider opening.

I'm open to using a suitable plastic base and concrete sections if required. The installation of the base will be an order of magnitude easier then trying to form my own chamber whilst the sewer is live.

Edit: https://www.drainagesuperstore.co.u...chamber-600mm-diameter-swept-cross-160mm.html

As you can see they aren't cheap though.
 
Don't think you'll find concrete sections any cheaper, and at least with plastic, you may be able to move them yourself and not need a crane!
 
Plastic sections are more than suitable for this application. I am currently in the process of a self build and despite carrying out rigorous utility checks, when we opened the ground for footings we discovered a 160mm (internal diameter) salt glaze pipe some 100 years old running across the entire footprint of the planned house. The pipe was a main line which served 4 existing properties, with a final invert depth of 1.4m where it entered the sewer run beneath the public road.

We cut the existing pipe, attached a flexible coupler to connect in a 160mm plastic pipe, and diverted the drain around the new property using 3 change of direction 350mm wide plastic inspection chambers and around 15m of linear 160mm plastic pipe. There are some regs about using a 'non-man entry' inspection chamber if the depth is below 1.2m which we had to adhere to (reducing the opening width), but this wouldn't apply in your case. We connected the new plastic pipework back up to the clay where it exited the boundary with another flexible coupler.

Building control signed it all off before we closed up the trenches.

I would appeal to the Water Operators before shelling out on concrete, using fit for purpose plastic will cost significantly less from both a materials and labour perspective!

Any queries give me a shout.
 
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