Clay drainage pipe advice needed

[tonyacktar]

Hi all

I have been asked by a customer to cut a channel in an old clay drain pipe and build a brick chamber/manhole around it to create an inspection chamber.
I have had some advice from an old timer who told me to dig to the bottom of the pipe but not under it and backfill with concrete half way up then slice the top off with a grinder and diamond blade and then brick up.

Has anyone done anything similar? any dos and don'ts

I suggested just cutting the pipe and inserting a plastic chamber and base but the customer wants to be able to put a slipper in sometime in the future rather than dig to the bottom of the chamber.

 

[Alpha man]

The old timers idea seems about right!, but building regs will want it done how you suggested!

 

[joni os]

In the 70s there was a minimum size for inspection chambers, this to allow man entry access. now there is a recommended maximum size to discourage man entry access. However, ever since the advent of flexible couplings rocker pipes should be provided either side of chamber to allow for differential settlement, this because pressure from direct loading on chamber differs from that on pipe buried in ground.
Cut clay pipe, length of chamber plus 600mm, keeping cuts well clear of any collars on existing clay. Then insert 300mm plpe either side of chamber and connect to existing with neoprene couplers. Provision for future connection can be made with external backdrop capped off until required.

 

[snowhead]

Is this drain Surface or Foul and is it Shared or for sole use by this property?

If it's Foul and shared it's now belongs to the Local water company and you can't just go cutting into it anymore.

 

[joni os]

Is this drain Surface or Foul and is it Shared or for sole use by this property?

If it's Foul and shared it's now belongs to the Local water company and you can't just go cutting into it anymore.

Could you give a reference for this. I have an estate near me full of 1970s pitch fibre foul drains, serving multiple properties. Tree roots, surcharge from overburden and subsidence continue to be problem. The house owners would gladly pass on the responsibility.

 

[snowhead]

https://www.citizensadvice.org.uk/c...-responsible-for-repairing-drains-and-sewers/

 

[joni os]

https://www.citizensadvice.org.uk/c...-responsible-for-repairing-drains-and-sewers/

Thanks for link. Careful reading of it indicates that not all shared sewers are owned by water authority. Contrary to your absolute assertion in post 4. Previously sewers less than 150mm were unlikely to be adopted and I have yet to encounter a water authority inspector when connecting to 100mm foul sewer on private land, even if serving multiple properties.