Hole in Alkathene Mains Feed

[ToGGoT]

Hi all,

Came home last night to a hissing from beneath the floorboards - eventually had the carpet up, and made an access hole through the floorboards, to discover our mains feed pipe has chaffed against a concrete block as it passes through under the house, and has finally created a pinhole.

The pipe is 3/8 inch Black Alkathene (I had to look it up) and is probably original from the early 60's. I gather you cant just buy the pipe/fittings any more, although adaptors seem to be available from a few manufacturers.

Looking at the pipe, usually they are marked Class C, or D - mine, typically isn't. Its just got "Alkathene N - BS 1972 1957" printed in red, on the side of the black 3/8 pipe.


We have currently "fixed" the leak with the aid of epoxy + a quantity of duct tape, and it is sealed (i.e, the meter isn't turning anymore with the internal stopcock turned off), but I rather feel a more permanent fix is probably a good idea. I think i'll need to remove a section of approx 4" where it has chaffed, but not so badly as where it is holed.

Best suggestions on how to go about this? I cant easily replace the whole pipe, as the previous owners have had the garden landscaped, and the pipe is now buried DEEP. Plus it has to go through behind next doors garden wall, which they wouldn't be hugely keen on.

Thanks

T

 

[ToGGoT]

What I am asking i guess is: Would it be acceptable to take a 2-3 metre section out of the pipe under the floor, fit a standard Philmac 20mm coupler with a red insert for 3/8 to each end, with a 2-3 metre section of MDPE with liners in the middle?

 

[Agile]

The water regs say the pipe should be between 750 mm and 1350 mm deep. So perhaps your "DEEP" pipe is too deep?

The obvious thing is to replace as much as you can with modern blue pipe at least 25 mm size using the connectors available to convert to your old black pipe.

Tony

 

[ToGGoT]

Ok thanks - that makes sense.

Are these appropriate connectors for the 25mm MDPE with a red adaptor for Alkathene?
http://www.yourdiyshop.com/building...ng-straight-25mm-to-20mm-connector-9132-p1412

T

 

[Agile]

That looks like the correct part and must be used with suitable inserts on each pipe.

But I am not an expert on mains water pipework and others may have useful comments to make.

Ideally replace everything from the place it comes into the house up to your copper pipework.

Tony

 

[BigSnoopy01]

plasson blue to black fittings are very good and you dont need any inserts on the black pipework. sold at Travis Perkins and other good merchants.

 

[andytw]

Here is the Philmac website http://www.philmac.co.uk/
Lots of info on there, you could contact them also.

My local agricultural outlet stocks vast range of Philmac fittings. You may have one near you ?