New water main, connection problem

[David.Rignall]

After receiving an astronomical quote from a 'plumber', we decided to install our own new water mains as it was the only way to correct the problem of very poor water pressure (shared water mains with our neighbour). Anglian Water have now seen us the price for them to connect their bit (=A3433) and I have ordered the mdpe pipe (the length is 30 odd meters). We are located near Towcester.

The trench has been dug to 750cm (the garden is looking like something from the first world war..) and the 100 year old steel pipe is now accessible.

My problem is how to connect the mdpe to the steel pipe? I am hoping there is an easier alternative that to, cut the pipe, cut a new thread and then make the connection.

The reason I can't just dispense with the steel altogether is that it enters the house and in embedded in a concrete floor. I have no desire to rip it all up. I'd rather just make the connection, outside the back door where the pipe enters the house.

Is there an easier way? I haven't used a tap / die set since I was 14 years old (over 25 years ago at school), so I am not keen to practise now...

[John]

I presume you mean 750mm? A trench at 7.5 metres deep must have taken some digging!!

Cheers

John

[Harry Bloomfield]

on 16/12/2006, John supposed :

He did say his garden was a mess :-)

I would not reuse any of the old pipe...

Get an SDS drill and it will go through the concrete like butter. If necessary you might be able to bring the new pipe in at a slightly better location to do the work, than the steel pipes present entry.

[Jim Alexander]

Check out the technical help here, doubt there is any need to do thread cutting but I'd be surprised if you can avoid cutting the pipe.....

The reason I can't just dispense with the steel altogether is that it

I'm with others who recommend trying to take the MDPE into the house. Breaking through the concrete floor is fairly trivial, getting under or through the foundations may be a bit harder. Extend your trench as far as possible and see what is revealled. Incidently how did your plumber propose to do the job?

Jim A

[ARWadsworth]

750mm is hard enough.

Nor would I

I totally destroyed a Makita HR3000C trying to do this. In the end I smashed up a small section of my concrete floor and then made good for a few pounds.

Adam

[The Natural Philosopher]

I cut through a 200cm thick concrete slab with a rotary slab cutter - hired it. Then you can use a pick on the rest..

That was laying an incoming electricity cable..

[Anna Kettle]

I cant help with your problem but out of interest how much was your quote? I shall be getting a new water main too though I'm thinking of finding a 'man with a moler' rather than dig up my lawn

Anna

[David.Rignall]

Yes, the trench is 750mm! deep, it was difficult enough to get to that depth!

Much as I might like to dispense with all the steel pipe, if I choose to replace it all I would have to rip up the hardwood flooring, excavate 1.5m of concrete slab, then connect the pipe up to the copper pipe in a false wall (which is currently unmolested). I really don't want the aggravation! I can live with 2m of steel and none of the aggro!

The original plumber seemed also keen not to make life difficult, he intended to connect to the pipe as it left the house.

So, given that I have to (for simplicity's sake) c> ARWadsworth wrote:

[Jim Alexander]

Oh well it was working when I posted. Try

Jim A

[David.Rignall]

The plumber (who is approved by Anglian Water) sent me a quote for just under =A34000. I thought this a tad high.

The cost so far to do it my self has been

=A3180 - To take out my extended family for a meal to pay for the trench day (32 meters of 750mm deep trench) =A345 Two lots of 50m*25mm mdpe blue piping (as we are doing next doors pipe as well because we are nice!) =A3433 To Anglian Water to pay for the connection. Approx =A320 for sundry items

Total cost =A3678.

I suspect I will buy 30m of larger diam tube to protect the water pipes in the trench. I suspect this should be no more than =A340.

We did consider moling but couldn't find a suitable person to do it. It may well have been cheaper/easier?

Anna Kettle wrote:

[Cicero]

================================ Is there any reason why the new pipe shouldn't rise outside and enter through a hole in the wall? It would need suitable protection from all possible sources of damage - both real and imaginary - but it's not unheard of. Mobile homes usually have their water supply connected like this with full approval I believe.

The old redundant pipe could be blanked and left in place for any possible future modifications in the same way that gas pipes are left.

If it's safe to have 22mm copper gas pipes on outside walls I see no reason why heavy duty plastic water pipe should be a problem.

Cic.

[David.Rignall]

But the difficulty with your suggestion is that we would have to have up to 2m of blue mdpe pipe going through our living room and then entering the false wall where the water pipe then goes upto the loft. We could box it in but thats more work. Our next door neighbour does have a similar type arrangement it 15mm copper pipe with a stop tap but it looks particularly ugly.

I've done an ascii diagram to illustrate

xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx x x x x x x x x x x x | x | | xxxxxxxxxxxxx x ========| x false wall x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

H> >

[Tony Bryer]

Frost. It doesn't matter how well you insulate the pipe as eventually its temperature will fall to the outside temperature (OK not quite true because of convection within the pipe)

[Phil L]

Firstly, I doubt whether the water board will connect a new main to a spliced pipe, they will want to see the main, in the hole prior to backfilling, they will also want to see where it enters the house, this part

*must* be insulated with 100mm insulation for around six foot, the part where it comes up from the bottom of the trench at 90 degrees under the floor/wall of the house requires a rigid plastic sleeve (these can be bought from most plumbers merchants) and the lagging and pipe are inside this, where it enters the house it will obvioulsy need a stop tap, all this will need to be in place before they will connect.

Attempting to join to steel is 1) almost impossible

2) a waste of time, money and effort considering it's heavily corroded inside, causing severe pressure problems, hence the need for a new main. and 3) as mentioned above, they probably won't connect to it.

HTH

[David.Rignall]

Assuming this is correct, how can I insert the new pipe through the floor and into the false wall without completely destroying the house in the process?

Is there a moling system that will be able to do this? Any idea's on whom might help with the next phase of the project?

Also, given that their are steel to mpde connectors available and that the connection is on our land, can't we just say to the water board to bog off?

Phil L wrote:

[Roger Mills]

Does it have to follow the *same* route as the old pipe? Isn't there any easier way to get it into the loft?

Possibly. By the same token, why involve the water board at all - why not put a steel to MDPE connector just on your side of the water board's stop tap?

But unless you replace the whole lot - from the external stop tap to the point where you need a decent flow rate - you may find that you haven't removed the bottle-necks, and you will have spent a lot of money to little avail. The internal pipework needs to be in at least 22mm copper or plastic pipe - and certainly *not* in rusty 1/2" steel.

[Jim Alexander]

People are trying to help, usually on the basis of been there done it.

Don't know your house so I don't know if some lateral thinking is needed. A

100 year old house, surely not a concrete raft foundation throughout? Any reason why so where the water comes in? Has the house even got much of a foundation? Access to an underbuilding anywhere? Just some of the questions that people that have been there will be asking.

Only if you tell us what the next phase is.

Well I think Phil L described the standards correctly. Not sure whether the water company would enforce them or not. When I got my supply changeover done, lead at the back of the house to MDPE at the front of the house, the changeover was scheduled for 11:00. Arrived back from work just before to find the changeover completed. The termination of the new pipe inside my house had not been checked. Fortunately it held. You can always tell them to bog off but you do want your new connection?

Jim A

[David.Rignall]

Given the very small size of the house, unless the pipe goes up the side of the outside wall (I've seen them do it with gas pipes but I'm not sure if it's legitimate to do it with water) there really is no other option than to follow the old course

The iron / mdpe connection is someway from the connection that Anglian water will do. Indeed, it is almost 32 meters away! The plan was to run two new connections from the bottom of the garden (where our single water main is) and then do the two connections just outside the doors so that we can both have water meters (which is not possible with our shared mains)

I'm hoping that our blockage is in the other 31 meters of pipe, given that both our houses have poor pressure which I assume indicated that the blockage is within the 'shared' section.

The pipe which emerges into the bathroom, on it's way up to the loft is

22mm copper so I suspect that the length of iron pipe left would be a mere 2m. (i.e from outside the house, going to the false wall)

On digging the trench we discovered that as some point the Water Board has indeed connected 'their' blue mdpe pipe to our iron pipe. My thinking is that if they can do it, why can't I?

Roger Mills wrote:

[David.Rignall]

I am grateful for all the advise and guidance given.

Our 'red brick' cottage was I suspect a cow shed some 100 years ago! Tragically, the flooring is a huge slab of concrete. Our water mains access the house via the back garden which is 32 meters long. Entering just 12" under the back door (which may have been the front door all those years ago!)

The next phase of the project is installing gas central heating! We have gas at the front of the house but currently we are all electric. Without proper water pressure, a combi boiler just won't work.

Hope that clarifies it?

Jim Alexander wrote:

[Jim Alexander]

In that case look at the HSS diamond drilling rigs. You might be surprised how reasonable the hire charges are. The secret with these would be to drill down at an angle calculated to break out into your trench extended just under the slab. Not sure if your £4000 plumber would have done it this way but I would have expected a competent plumber/builder to do it that way.

Accepting that your flow is currently poor are you confident that you have adequate static pressure, because without that no amount of new pipwork will give you good flow? Not convinced that is the case from anything you have said.

Well if you ask the question in the NG I know you will get plenty opinion about that.

Jim A