Manhole covers

[Jackthebiscuit]

Hi All,

I have a manhole cover which needs replacing, it's in a domestic garden so light duty OK. Are old size manhole covers available?

The dimentions are 20 inches x 26 inches or 51cm x 76cm. Nearest I've seen is 45cm x 60cm. I'll change the rim also but would prefer something closer to the existing size.

Also, if building an extention over an existing manhole, what are the rules? The extension will be a bedroom.

Thanx

 

[plumskull]

Hi All,

I have a manhole cover which needs replacing, it's in a domestic garden so light duty OK. Are old size manhole covers available?

The dimentions are 20 inches x 26 inches or 51cm x 76cm. Nearest I've seen is 45cm x 60cm. I'll change the rim also but would prefer something closer to the existing size.

Also, if building an extention over an existing manhole, what are the rules? The extension will be a bedroom.

Thanx

Go ahead, if your manhole is in your bedroom then all the more easier for Batman to enter, it`s a no brainer for me to be fair.

 

[Onetap]

Hi All,

I have a manhole cover which needs replacing, it's in a domestic garden so light duty OK. Are old size manhole covers available?

No, there are no standard sizes, but you may find one that fits.

Internal manholes are no longer permitted. You'll have to shift it.

 

[D_Hailsham]

Also, if building an extension over an existing manhole, what are the rules?

This may help! Building over Sewers

 

[Jackthebiscuit]

Thanks D_Hailsham

Yes, the link was very useful.

Thanks Onetap,

Any idea of a supplier of manhole covers?

 

[Jackthebiscuit]

Me again guys,

Seems I have been misinformed, as 'batman' can indeed enter a bedroom with an internal manhole as I've been informed that it is permissible.!!?

 

[namsag]

If its within the building you need an air tight one so it not just a case of replacing with any sort, have a word a local builders merchants somebody there will usually be able to explain things

 

[Jackthebiscuit]

yes namsag, this is what i thought, and on another thread they have corrected what onetap and err,,, the 'no brainer' plumskull said.

 

[Agile]

Unless the regs have changed an internal inspection cover ( they cannot be called manholes any more ) must have a double seal and be screwed down.

Contrary to what you have been told there are many which are to a standard size, perhaps 21" x 26¾" if they are the same as the ones here.

But there are also many of other odd sizes.

Tony

 

[Onetap]

yes namsag, this is what i thought, and on another thread they have corrected what onetap and err,,, the 'no brainer' plumskull said.

Thames Water (since you're in London) won't allow you to build over a manhole on a public sewer (serving houses other than your own) regardless of how many seals and holding down bolts it has. You'd have to move the manhole.

If the sewer only serves your own property, then it's my belief that it's your property and you can pretty do much as you like.

The local council's Building Inspector recently blew in to inspect works on an extension I'm involved with. He instructed the builder to move the manhole so that they would be outside, without any knowledge of what they served. They are on public sewers and were due to be moved anyway.

 

[Jackthebiscuit]

Unless the regs have changed an internal inspection cover ( they cannot be called manholes any more ) must have a double seal and be screwed down.

Contrary to what you have been told there are many which are to a standard size, perhaps 21" x 26¾" if they are the same as the ones here.

But there are also many of other odd sizes.

Tony

Yes Tony, I found one very similar in size to the existing and it has been installed.

 

[Jackthebiscuit]

yes namsag, this is what i thought, and on another thread they have corrected what onetap and err,,, the 'no brainer' plumskull said.

Thames Water (since you're in London) won't allow you to build over a manhole on a public sewer (serving houses other than your own) regardless of how many seals and holding down bolts it has. You'd have to move the manhole.

If the sewer only serves your own property, then it's my belief that it's your property and you can pretty do much as you like.

The local council's Building Inspector recently blew in to inspect works on an extension I'm involved with. He instructed the builder to move the manhole so that they would be outside, without any knowledge of what they served. They are on public sewers and were due to be moved anyway.

Hello Onetap,

Your initial reply did not distinguish between a public and a private sewer, you just said it wasn't allowed, and others have disagreed. I think the criteria as to what I can do may depend on whether the sewer is private or publicly owned. I assume that if the chamber became blocked that it would be my responsibility for it to be cleared, and if it were a public sewer then it would be the responsibility of the local authority. I'm almost certain that unblocking it would be my responsibility as though it is linked to neighbours sewers,,, it is on my land. So applying this logic I 'think' that it is private.

The houses were built in 1935 and are a fairly typical case of a sewer line running through the rear gardens, with each house having it's own manhole/inspection chamber where their waste pipes connect into the main run. In this case the sewer serves about 16 houses and is a straight run from top to bottom, and my house is midway. If I were to move my manhole and associated drains outside of the proposed extension line, then I would need permission of at least one neighbour-and perhaps both- to excavate their gardens and re-route the main sewer line. In effect I would be installing a dog-leg into what is now a straight run. Logic tells me this a worse solution than just changing the cover of the existing manhole to a double seal type for indoor use.

Others in the location have built extensions over manholes, but none recently, so do need to confirm what the latest regs permit.

 

[Jackthebiscuit]

Error

 

[Agile]

That can alter the situation as you now tell us its a shared drain.

It may also depend on the size. Individual houses are usually 4" and shared are 6" if serving more than about four houses.

I suppose the correct advice would be to ask the local water authority.

Or just go ahead and do it like the others.

BUT if it will be inspected by your local building control they may have their own views too. My limited experience though is that they are not interested in what it serves only that its correctly protected where its built over.

Depending on a few factors it may be maintainable by the water authority. If you check the size you could try asking them.

I had a solicitor for the old neighbour spend £900 digging up her drain but not solving the problem. When I was consulted, I had it relaid where it had collapsed at the cost of the water authority with the work done by the LA as their contractors.

Tony

 

[Jackthebiscuit]

That can alter the situation as you now tell us its a shared drain.

Tony

Tony,

So how many dwellings in London are not 'shared' drains!!!!?? Was it not a fair assumption given my location that others would be on the same line?

To proceed without prior knowledge of the regulations is foolhardy advise,,, and not an option.