Can I extend over a manhole?

Herzlos

I suspect the answer to this is no, but I thought I'd check before spending ££££'s on surveys and plans, etc.


I've got a fairly standard house with a driveway down the side and a garage at the end, and a small gate between garage and house, like this:

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[FONT=Courier New]       |               |[/FONT]
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[FONT=Courier New]   O   |    House      |[/FONT]
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On the driveway, there's a manhole (I've never opened it to see where it leads, and it's under a few tons of gravel). Going by the house it's either just an access for something, or a tunnel that leads under the garage/gate. It's unlikely anyone remembers it's there.


I was wanting to extend the house over the driveway, something like this:

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[FONT=Courier New]|      |               |[/FONT]
[FONT=Courier New]|------|               |[/FONT]
[FONT=Courier New]|  O   |    House      |[/FONT]
[FONT=Courier New]|      |               |[/FONT]
[FONT=Courier New]--    -|               |[/FONT]
[FONT=Courier New]       -----------------[/FONT]

Where the bottom of the extension is a garage, and the top/back is a utility room. Thus the manhole would be in/under the garage floor (likely poured concrete around the cover, and then I'd line it with something like laminate/lino, so it'd still be accessible should anyone ever need it (and probably with less effort than lifting the gravel).



Am I going to be completely screwed at the planning permission stage from an access point of view?
Will I be able to lay any foundations if it's likely to disturb whatever is accessed or if the ground isn't solid?

Gloomendoom

I'm not sure planning would be bothered. Building control might be though.

That said, I have a manhole inside my house.

Doozergirl

It all depends on what is going through the inspection chamber. If it is shared, then it requires a build over agreement from the water company. If it's purely yours then you don't need a build over agreement.

But it would require re-siting as building regulations won't allow an internal manhole anymore, for good reason.

-taff

If you're a semi, it's likely to be shared.

Herzlos

Thanks all, so I'd be on the hook for getting the water company (or whoever owns it) to move the hole out of the way? That sounds like a nightmare.

FreeBear

Herzlos wrote: »

Thanks all, so I'd be on the hook for getting the water company (or whoever owns it) to move the hole out of the way? That sounds like a nightmare.

If the manhole only serves your property, then moving it is an option. But the only way you will know for certain is to lift the lid and look to see where the pipes go. burying it under a tonne of gravel was not a good idea, neither is laying a slab of concrete over the top.

Davesnave

To be fair, the OP didn't suggest pouring concrete over the top, but they didn't do themselves any favours covering up the chamber lid with gravel. Also, the least they could have done before coming here was look inside, because that would give some clues about visible/ probable pipe runs.

OP, it's as Doozergirl says: if drainage from a neighbour passes through this chamber, it's the responsibility of the water authority and their decision what you can do. If it's your effluent only that's passing through, you can move it, so long as that doesn't then interfere with any shared drainage.

The rules are also a little more complex than that, because digging foundations etc within 3m of any shared drainage pipes also needs permission, so you really need a map of the drainage runs in your immediate area.

Apodemus

If it is a rodding access for your sewer pipes at a 90 degree bend, then moving the access might make sorting any future blockages more tricky.

...but I am still concerned with your statement that you would be putting Lino or laminate over it...in your garage? Which suggests to me that your real intention is to use this space for something else?

Herzlos

Davesnave wrote: »

To be fair, the OP didn't suggest pouring concrete over the top, but they didn't do themselves any favours covering up the chamber lid with gravel. Also, the least they could have done before coming here was look inside, because that would give some clues about visible/ probable pipe runs

It was under gravel when I moved in, all I did was replace the gravel. The intention was to put a concrete floor in the garage, leaving the access intact.

...but I am still concerned with your statement that you would be putting Lino or laminate over it...in your garage? Which suggests to me that your real intention is to use this space for something else?

It likely won't be able to fit a car in (like most modern garages) so would be more for trailer/bikes/tools. I've done this with the current garage with foam gym tiles for insulation, where I can still get a car onto it. Something like this