Rising main

[geraldthehamster]

I asked this on the tag end of another thread, but here is my question in all its glory.

When I redo my kitchen (again), I'm going to need to bring the mains water in at a different point, from the outside. Obviously I'm keen not to have to go under the foundations. Is there an approved way to bring the mains above ground outside the house, and through the wall, using insulation, and are there bits of kit made specifically for this purpose? A desultory Google has brought nothing up.

Cheers Richard

[geraldthehamster]

I asked this on the tag end of another thread, but here is my question in all its glory.

When I redo my kitchen (again), I'm going to need to bring the mains water in at a different point, from the outside. Obviously I'm keen not to have to go under the foundations. Is there an approved way to bring the mains above ground outside the house, and through the wall, using insulation, and are there bits of kit made specifically for this purpose? A desultory Google has brought nothing up.

Cheers Richard

[Lobster]

Well, when I had to lay on mains water from scratch to a do-er upper a few years ago, I had to jump through the water company's many hoops in that regard. The pipe had to come in from the street through the wall of the foundations at a minimum prescribed depth, and be sheathed in insulation (the preferred way was to use a special purpose-made curved plastic pipe about 4" diameter, filled with foam insulation). They were really fussy and came to inspect, demanding further changes before they'd approve the work. I can't imagine the rules being any different for what you're proposing.

David

[The Natural Philosopher]

No, and its bloody inadvisable. And IIRC contrary to building regulations.

That is exactly how to get a burst water main OUTSIDE the internal stopcock.

Mains water has to be down at least a half a meter from memory until its INSIDE the property and protected from siberian blasts etc etc.

You can extend outside underground, or inside - your choice, but neither will be simple or cheap.

Drilling through foundations is not the end of the world, and neither is chasing down below the main stopcock to find what's there, and extending in in a trench in the floor.

Your best bet to drill through te foundations is to excavate outside as deep as you need to and then from inside drill with a heavy duty core drill or similar from floor level inside at a fairly steep angle down.

The better way - but its messier - is to remove a largish section of te floor and dig down to at least 30mm below soild and then drill horizontally.

This is definitely one of those questions that my .sig is designed to highlight: Moving water and drains in a house is a BIG job. It seems trivial. It never is.

[The Natural Philosopher]

+1

[Tim Watts]

I redid the mains where it entered my house and they did not care - I did ring them, mostly to get an idenfication on the type of pipe I found ouside (1/2" alkathene as it happens).

I went under the foundations 2' down (old house), fed MDPE through a 4" drain rest bend which had a 50mm adaptor on top and a bit of 50mm drain pipe coming up to floor level.

Put an MDPE universal coupling onto the alkathene pipe again 2' down, built a little brick chamber around the joint for inspection reasons with a lid on top and back filled the hole under the house with well rammed concrete.

No insulation and no signs of freezing even last winter (2010-11).

The water company even offered to do a free reconnection to the main c*ck (bang on my boundary) if I wished to run the MDPE out there.

For a new development, they are likely to be fussy - for a modification, don't bother talking to them - just do it.

Insulation is a good idea if you can - but there's no point in being paranoid - pipes round here that I've seen are no deeper than 2' under the drives (stop c*ck position) and we don;t get problems.

[Tim Watts]

I'll just add that It's actually not that hard to get in under the foundations. I would not run it up the outside wall.

I dug a 3' deep hole, 3x3' wide (looking for the original pipe) then used an iron bar to dig out a small hole in the earth under the foundation strip.

Fron the inside, I used a 60mm (ish) TCT hole drill in an SDS to bore vertically down through the concrete floor over the hole. Internal damage was minimal.

[geraldthehamster]

Thanks Tim.

The setup is: the water co's shut-off valve is just inside my property (actually a water meter that we inadvisedly had installed, before using the 12 month cooling off period to go back on the water rates, when we realised how much we were using!). The house is about 20 feet from there, but the existing main comes in at the back of the house, as 15mm or 1/2"copper pipe emerging mysteriously from the floor, which is all I can see.

I've no idea what's under the ground (house built 1963), but I may need to replace back to the meter; alternatively maybe I could save digging by joining MDPE to the existing pipe nearer the house, with an inspection chamber? I do have an alternative route in via the utility room, which is a later addition and (I have reason to believe) has shallower footings than the kitchen.

I'm keen to avoid attacking the kitchen floor again - I've had to do this once to route some internal water pipes, and I've seldom encountered anything harder than that 1960s concrete.

Cheers Richard

[geraldthehamster]

Thanks, this is useful. I can visualise how to do it now.

Cheers Richard

[The Natural Philosopher]

it will probably be 22mm if its reasonably recent.

TBH unless there is a concrete drive or summat in between, I'd dig right back to the stopcock there and redo the whole thing in well laid MDPE - the pipe is not expensive and a digger will cost you a couple of hundred max and will make short work of the trench ...no need for inspection chambers - more trouble than its worth.

yes. sometimes they did things right..well its kango time innit?

IF you CAN get under the foundations in toto then that's a good way to do things.

Its not impossible either to do a semi bridge job and insert a concrete lintel into the foundations and remove a small section below.

A digger down the side of the footings will reveal all.

then decide.

[js.b1]

There are 2 occasions when water regs are not broken, but worked with at some cost.

#1 - Depth

- For example where there are public services (Schedule 24) pipe traversing the area making requisite depth impossible.

- Solution is the usual blue conduit, but with special waterproof insulation inside it around the pipe.

- Cost per 2m appears reasonable (under =A320), but realise when done things are going to get really quite expensive.

#2 - Entering a property.

- For example proximity to ducts (eg, mains grid) or raft with keel thickness (eg, 5 feet).

- Solution is a special lined box which is sunk to the required depth outside and extends up the external wall. It usually houses a stopcock and enters above ground.

- Cost is high, about =A3180 just for the parts including insulation.

Both the above are widely used - for example

carry them.

See...

- Water Meter Box - Groundbreaker 3 - 20241 - =A3120 inc VAT.

- PIPE PROTECTION BOX - INSUduct=99 - 16791 - =A350 inc VAT

- INSUDUCT=99 MDPE PIPE - Hockey stick for box - 17969 - =A310 inc VAT

Water should be laid at 750mm depth. Right smack through two 24" Schedule 24 pipes and Railway Undertaker's will suggest this solution too.

- WATER SERVICE DUCTING - 900 mm x 35 mm SHalloduct insulation - 19170

- =A310 for JUST 90cm!!

- 4" x 3 m blue Rigiduct pipe - 3000mm x 4" blue rigidpipe duct -

18515 - =A35.66 for 3m.

So if you had 30m to insulate, not unreasonable that is =A3360 for the insulated duct... plus =A360 for the insulated pipe protection box... plus =A3120 for the water meter box... plus an external quality valve at =A320.

Compliant with water regulations for frost protection and DETR guidelines, including water regulation guidelines G4.4 - .12. You can not make up your own insulation, I suspect it is simply extruded polystyrene (closed cell), moulded to fit the ducting.

Nothing to stop you using trace heating tape in the outside box incidentallly... not much length required.

The boxes have special gaskets to seal against the brickwork incidentally. They seem well regarded. Colleague used one setup, the water company baulked at first, he quoted the details and they sent someone back to do the communication pipe work and that was it.

[js.b1]

Some performance specs...

Tested against Water Industry Standard 4-37-01.

- Resistant to temperatures at 0oC for at least two weeks

- Resistant to temperatures -15oC for a minimum of three days

- Test results being scrutinised by Water Research Centre (WRc) and certified by the Water Regulation Advisiory Service (WRAS).

"In both these tests Groundbreaker exceeded the test requirement by some considerable margin". I dislike marketing drivel like that, I would much rather the WRAS report with actual test results be provided

- such as "0oC for 16 days" or "-15oC for 5 days".

Anyhow, for comparison 100yr winter did have average temperature below

0oC for some time and about 72hrs ranging -8oC to -22oC so average probably did hit -15oC. So it looks like a "once in 150yr winter" could produce conditions more severe than the test, but other than that it looks ok and is certified by WRAS. I would still consider heating tape if unoccupied, a couple of feet self-regulating does not cost much... just don't make it solar powered :-))

[jregraham]

What size / spec / radius rest bend did you use? I'm worried about creasing the 25mm pipe. Cheers.

[John Rumm]

Give us a clue old chap, quote some of the message you are looking at so we know what you are talking about!

[Jeff Layman]

It's in reply to a 5-year old post. You can find it here:

[Brian Gaff]

Its obviously one from beyond the grave so its not possible. Brian

[John Rumm]

Well its possible (since the OP managed to find it on google groups), and no doubt other archive site will have it.

However it would seem not unreasonable that the person asking the question does some of the work!

(this is no doubt the usual problem of people using gateway sites to usenet and not realising what usenet is or how it works. They probably think we are all their glued to gg reading that "forum")

[Andy Burns]

What's harry's excuse for responding to an 11 year old post from TNP about gluing wood to plasterboard?

[John Rumm]

Just being consistent with his public display of competency.