Blocked drain following extension work

[Northernlad22]

We have lived in our house for 15 years and never had a problem with drainage. We are having an extension to the side which has involved drainage works. The week after our upstairs toilet blocked in the pipe work outside, which will apparently require some work to fix it. Could the drainage extension works have affected the toilet? It has never blocked before ever and seems a bit coincidental to block now.
Thanks for any advice.

 

[freddiemercurystwin]

Could be linked or a coincidence, can't answer without knowing what's connected to what/the drainage layout showing existing/new etc. Who said it needs what work to fix it. More info required.

 

[JohnD]

have a look down the manhole.

sometimes people wash their tools down drains, including buckets of plaster, grout, mortar and concrete mix

sometimes diggers break drains

sometimes people flush inappropriate objects down toilets

 

[Hugh Jaleak]

Does seem rather a coincidence, (it's amazing how much stuff 'accidentally' finds it's way into drains during Building work...) Cannot say for certain without being there, and will depend on what blocked it, where and how it got there.

 

[Northernlad22]

have a look down the manhole.

sometimes people wash their tools down drains, including buckets of plaster, grout, mortar and concrete mix

sometimes diggers break drains

sometimes people flush inappropriate objects down toilets

Thank you for your ideas. I don’t think they’ve washed tools down there as it’s blocked upstairs round the back and the workmen have been on the front/side only.
The digger has been in the front so not near the drain that’s blocked.
The builders haven’t used our toilet and our household don’t flush anything other than loo paper.
The blockage is just past the soil pipe and backed up into the soil pipe. The manhole downstream by about 3-4 metres was clear with a rod up towards the soil pipe except for a couple of feet after the soil pipe if that makes sense.

 

[Northernlad22]

Does seem rather a coincidence, (it's amazing how much stuff 'accidentally' finds it's way into drains during Building work...) Cannot say for certain without being there, and will depend on what blocked it, where and how it got there.

It is just blocked beyond the upstairs toilet, ie soil pipe backed up and a couple of feet beyond that. To be fair the workmen haven’t been anywhere near that area. I was just curious whether anything they’d done downstream could’ve affected it. One bathroom is still draining through their new manhole fine, it’s just the other toilet soil pipe that blocked and all seemed a bit coincidental after 15 years never having a blockage.

 

[Northernlad22]

Could be linked or a coincidence, can't answer without knowing what's connected to what/the drainage layout showing existing/new etc. Who said it needs what work to fix it. More info required.

Thank you. I don’t entirely understand but will try to answer. The upstairs toilet feeds into the drain down the side of the house which runs to the front where the builders have attached some new pipes for the extension and moved the manhole downstream. I asked the builder if his works could’ve blocked the drain, he said not and that we need another manhole cover putting in where the second toilet is upstairs. He said there should be one by every soil pipe.
The original fixed price job has had several other jobs added on already so I just want to check I’m not being taken for a ride.