Replacing clay pipe main sewer

[Donk]

We have a new build coming up and the sewer is bang through the middle.

It's 150mm clay pipe, we need to divert it but am told that normal 150mm plastic pipe cant be used for 'main sewers' it needs to be ribbed plastic.

Anyone have a spec or link to the regs on this ?

Also can we use plastic 450mm chamber where we joint into it or does this have to be concrete rings type affair ?

Lastly, the side of the plot where the sewer exits downhill, we have 900mm space between building and the boundry to make the new manhole. Will this be enough if we cant use 450 chambers ?

Lastly I guess would be to dogleg the sewer under a corner of the building to make room in the front garden for the manhole but that means build over (we need build over anyway due to 3m rule).

All advise appreciated!!

thanks!

[jwill]

I think you will need method statement and all that jazz also will be overseen by bco. Talk to building control once your drawings are approved by them then go from there. They would prob want replacing with clay

[seanandruby]

Have a read of sewers for adpotion and also building regs' part h. As said by will talk to your building control to see what they say

[Tony McC]

Sewers for Adoption 7th ed. Essential reading for exactly this sort of scenario.....

[Donk]

thanks all for the replies, as no one seems to know the answer I'll report back when I found out for future ref.

[seanandruby]

To answer your question. I personaly have only ever done industrial units. On my jobs we normally place a shutter and concrete a base with a metal sealed unit bedded in situ. We build the base in such a way so that there is a 100ml kicker. This kicker has a 20ml rebate all around in the centre of ( if used ) rebar starter bars. When the concrete has gone off next day, the rebate is removed and a strip of hydrotite joint is placed in the rebated joint, it has to have a primer painted on first to help adhesion. The hydrotite is normally placed prior to concreting to keep it dry. It expands once exposed to wet concrete. The manhole is usually formed with either wet concrete, or brick depending on spec'. It is a awkeard comlicated job if it is needed, not a task for the diyer. A double seal cover should be used. As said..." it depends on your building control officer."

[Dave_L]

This work will normally need to be carried out by an accredited contractor, many water campanies have their own approved contractors. Have you been in contact with them?

[Donk]

just to follow up on this in case anyone needs for future, the correct pipe is this ribbed type:

http://www.polypipe.com/civils-....e-pipes

[rxbren]

450mm manholes can be used to depth of about 1m
if you cant use a 450mm chamber and the concrete sections are too large you can build a manhole out of 9" brickwork
should have inspection chambers on all change of directions with max 45 degree bends in and out although if its only foul for that property depending on who is signing it off you could possibly put a rodding eye in

[seanandruby]

...450 is an I C, not a manhole. A manhole can be entered with full cofined space regs' if needed, an I C can't be entered, it is for remote inspection, cleaning and testing only. The universal I C is good up to 1200 only, adoption, or unadoption. Anything deeper requires the special design I C which has a single 3 metre raising piece and is a lot stronger to take the loading of the fill material etc: other than that would require brick, concrete etc: especially in roads.