1. Visiting from the US? Why not try DIYnot.US instead? Click here to continue to DIYnot.US.
    Dismiss Notice

Help/Advice for small rear extension (drain issues). inc pics...

Discussion in 'Building' started by pb2012, 17 Mar 2018.

  1. pb2012

    pb2012

    Joined:
    24 Feb 2012
    Messages:
    62
    Thanks Received:
    1
    Country:
    United Kingdom
    Hi all,

    I'm looking to buy a new property and it hinges, to a fair degree, on the ability to create a little more living space.

    I've attached 4 images to this post.

    basement-floorplan-options.jpg:
    basement-floorplan-options.jpg
    What I'd like to achieve. option is 1) is a fallback, Option 2) is preferred, and option 3) would be no extension at all (not so much of an option!).

    back1.jpg:

    back1.jpg
    Full view of the rear.

    back2.jpg:
    back2.jpg
    Isolation of manhole/drain cover.

    back3.jpg:
    back3.jpg
    Illustration of planned extension in relation to pipes etc.

    My questions are:

    1) How much of an issue would you think that the manhole is? I'm happy to not move or build over it, but I need to at least go right up to it. I'm hoping no unexpected extraneous work would be needed with this.

    2) Can you see any issues with re-routing the central drain pipe, and current internal sink pipe? Can I just run these off in to a relocated drain further down the garden?

    3) Could the manhole to the left be used when re-configuring the current drain pipes?

    4) are there any other issues I should be aware of that would kill or limit the extension plan?


    If anything is likely to create a lot of complicated work and extra cost that would be an issue.

    Thanks in advance for any help!
     
    Last edited: 17 Mar 2018
  2. ^woody^

    ^woody^

    Joined:
    3 Sep 2006
    Messages:
    26,271
    Thanks Received:
    3,238
    Location:
    West Mids
    Country:
    United Kingdom
    It's all probably. Don't buy a house based on some random forum opinion - even if its quite good opinion.

    Get it surveyed and instruct the surveyor to comment on the viability of whatever you want to do with the place.
     
  3. pb2012

    pb2012

    Joined:
    24 Feb 2012
    Messages:
    62
    Thanks Received:
    1
    Country:
    United Kingdom

    Fair enough. I think if it turned out that an extension was simply impossible for any reason I'd still go for it. It would just be a bit less ideal.

    I think that forum opinion and comment is still valid. Perhaps I can get some ideas I'd not thought about, and be better informed when it comes to having conversations with builders and planners.
     
  4. Notch7

    Notch7

    Joined:
    15 Sep 2017
    Messages:
    11,581
    Thanks Received:
    951
    Location:
    Sussex
    Country:
    United Kingdom
    rainwater downpipe is no issue.

    Kitchen gully no problem

    Manhole -problem!
    if its a sewer run joining other properties -very common on terraced houses, you will need a build over agreement from your local water authority (which is not guaranteed). Build over should really be called build near to -as agreements are required if you build within 3 metres (from memory). If you build to miss the manhole, you prob need to be 500mm away.

    foundations need to be 150mm below invert level -so you need to know how deep the pipe is.

    You will be building within 3 metres of the neighbours foundation so may need a party wall notice.

    Hopefully you dont have bats, newts, roman remains, knotweed, TPO trees or anything else requiring an expensive report :D
     
  5. pb2012

    pb2012

    Joined:
    24 Feb 2012
    Messages:
    62
    Thanks Received:
    1
    Country:
    United Kingdom
    Yea, damn that manhole! I think a 500mm clearance would just about be an issue. I'd ideally like to build just beyond the back door which would be pushing it.

    I suppose I need to get the cover up and see what's going on under there.

    If it is of any consequence, the main sewers and their access seem to run at the front of the property. There are lots of standard manholes along the pavement and in the middle of the road.

    I have a suspicion there is a sewer run under that back-garden cover and this house is at the end of it, then leading under the property to the main sewer.
     
  6. ^woody^

    ^woody^

    Joined:
    3 Sep 2006
    Messages:
    26,271
    Thanks Received:
    3,238
    Location:
    West Mids
    Country:
    United Kingdom
    Of that age, all the drains are likely to be public sewers (maybe combined?) so you are in the hands of the water authority as to what they will allow.

    If there are other similar extensions then its possible you could have one too.

    Otherwise you are into a load of guesswork on here about what may and may not be possible. Looking at it, its a straightforward extension with the usual technical solutions. But what they may be and at what cost you wont get here.
     
  7. Ian H

    Ian H

    Joined:
    14 Sep 2010
    Messages:
    5,632
    Thanks Received:
    613
    Location:
    Rochdale
    Country:
    United Kingdom
    If the drain starts at your kitchen gully then goes left into the neighbours it would be much easier. You need to lift the lid.
     
  8. pb2012

    pb2012

    Joined:
    24 Feb 2012
    Messages:
    62
    Thanks Received:
    1
    Country:
    United Kingdom
    I have a bit of an update on this.

    I got a sewer map for the property and area. As you see below, the manhole/drain isn't recognised on the properties plot (No.47). We can also see that the property is at the start of the run, not the end (which must be a good thing):

    sewer-map.jpg

    It leaves a question regarding a build-over agreement. Would my proposed extension go within 3 meters of a public sewer?

    Looking at the 2011 sewer transfer regs, it seems the drain/sewer on no.47's plot is not public sewer, and the run through to next door is also not public, but 'lateral':

    public-sewer-diagram2.jpg

    I 'think' this puts me in the clear, but would need confirming. Does anyone know who I'd need to get out and confirm it? Would it be someone from the Water Company themselves, or just a planning officer from the local building regs department?
     
  9. Ian H

    Ian H

    Joined:
    14 Sep 2010
    Messages:
    5,632
    Thanks Received:
    613
    Location:
    Rochdale
    Country:
    United Kingdom
    I'd just crack on if I were you.
     
  10. DIYnot Local

    DIYnot Local

    Joined:
    3 Sep 2019
    Country:
    United Kingdom

    If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

    Select the supplier or trade you require, enter your location to begin your search.


    Are you a trade or supplier? You can create your listing free at DIYnot Local

     
Loading...

Share This Page