Sewer and extension

L1011

I lifted the inspection hatch on what I had thought might be storm drains, and it appears to be the full sewer - soil stack drains in to it and it runs from the house(s)s next door and down through the house(s) the other side - house is in the middle of a block of five.

The drain is about one metre from the rear wall of the house. Its not marked on the folio map, but I've not checked any pre-folio paperwork (built 1972, first folio entry is 1998).

Does this completely prevent building an extension without diverting the sewer line, if that's even possible?

rayjdav

If it is shallow you might not be able to divert it. You will need to allow minimum falls for the waste to disappear.
What I have seen is leaving the route in place, just replace the length of pipe when your at it, but provide an aj just before the extension and just after.
(Remember to cap the sewer on the inlet side 1st :D:D)

Penn

L1011 wrote: »

I lifted the inspection hatch on what I had thought might be storm drains, and it appears to be the full sewer - soil stack drains in to it and it runs from the house(s)s next door and down through the house(s) the other side - house is in the middle of a block of five.

The drain is about one metre from the rear wall of the house. Its not marked on the folio map, but I've not checked any pre-folio paperwork (built 1972, first folio entry is 1998).

Does this completely prevent building an extension without diverting the sewer line, if that's even possible?

Doesn't completely prevent it, no. There are standard construction details for building over sewer pipes. It's mostly going to depend on the depth of the pipe to determine any restrictions on depth of floor construction over it.

Though as rayjdav said, it's also best if you provide a new AJ on the line at the side of the extension to allow for periodic rodding and inspection.

You can also call the council and ask for the water services maps (particularly drainage) for the site. It may have them shown on it, as well as invert levels of the pipe at each end.

sydthebeat

Also be aware that of you are building over a shared sewer... you need permission... regardless if the sizes etc come under the exempted development regs

L1011

Its pretty shallow - had to lift two hatches to get to it, one in the newer patio and one at the original concrete level below, but it wasn't deep under that. Access to the side(s) would significantly limit the width of a potential extension to a terraced house to something in the middle (bit like a Victorian return!).

Permission is unlikely to be an issue in terms of objections but obviously a further cost.

Just considering whether to move, extend, or cope with restrictions of the house really, may actually spend some cash on getting a professional to come up with suggestions!

L1011

Council have provided me with the water and waste maps and there is absolutely nothing recorded for waste for my entire estate except a single line across the back of one row of houses, and a spur for an infill house.

At least I know the water supply lines are PVC not lead now!

Gumbo

You either reroute or design the extension around the manhole.

The Continental Op

Can you block it for a few hours so you can see what comes along?

An chance its just a drain for rainwater?

Gumbo

The Continental Op wrote: »

Can you block it for a few hours so you can see what comes along?

An chance its just a drain for rainwater?

Doesn’t matter whether it’s foul or surface, the access still needs to be maintained or alternative access and rodding points provided as per the building regs. Part H.

L1011

The Continental Op wrote: »

Can you block it for a few hours so you can see what comes along?

An chance its just a drain for rainwater?

I've verified with my own inputs in (running taps) to it that its foul.

If I could move it a few metres upstream it'd allow for a half-width extension to one side which would be sufficient and is common enough in the entire estate - very few people have full width extensions at all.