Help... Multiple Underfloor leaks in new build!!!

johnnyjoseph

Hi. I'm new to posting, but am a regular reader. Hoping you all could give me your opinions on the following;
We are building a new house using a building contractor. Plan was to have underfloor throughout house, heated by an oil burner. The ground floor underfloor pipework was layed on top of insulation last winter. Seemingly it was pressure tested with air and water (???) and all checked out ok. Then the screed was poured over. Only now getting heating onto house. Pressure is now dropping in multiple loops. 4-5 leaks found already on different loops. These have been repaired by removing small sections of screed, cutting out the small sections of damaged piping, and joining it with new small sections. I've been told that there must have been residual water left in the piping after the initial pressure test which must have froze, causing cracks/deformities. When the heating was turned on recently, these cracks must have got bigger and then started to loose pressure.
My questions are;
1. Is the whole integrity of the underfloor piping at risk, ie, will there be more and more leaks found into the future? If so, should I just have the whole thing removed now (a massive task I know!).
2. Is this a common problem with UFH?
3. Will there be problems with the 'new' joinings on the pipework? I know the loops are usually one continuous pipe back to the manifold.

Billy Bunting

Not something that normally happens with this piping but if it is as you say i wouldn't trust any of it into the furure because although not all leaking it as surely all had a good blast and who knows what awaits.

heinbloed

I totally agree with Billy Bunting. What was the name of the builder/installer?

johnnyjoseph

Thanks for inputs.
I'd rather not say who the builder/installer was. They do have a decent reputation though.

Carlow52

Interesting one from a liability perspective. Before you proceed with the breaker you need to figure out who is paying and if the builder says his insurance process the claim first, ditto if your insurance.

From a solution perspective it needs to be dug out and redone, unless you have the (head)room to add on another layer of screed or else look at retro fitting rads

nophd08

A massive task to replace, but builder has to be at fault, Water would have been left in pipework after testing so frost will have done its thing. Retrofitting rads is a compromise but its UFH you are paying for.
What you can do is pressurise all UFH pipes to twice normal working pressure and leave test on for 24hrs, if it doesnt leak in that period then you should be ok. Be sure you are there to witness test and keep checking pressure guage yourself.

heinbloed

The next pressure test (when re-building the installation) should be done dry. A simple air pump as used for car tires would do the trick.

Jedstaff

If you are thinking of ripping up the floor, another option I'll throw to you is poly therm heat track. Basically it's ply-wood nailed to your concrete floor ,15 mm thick with tracks in it for the pipe to sit in.I've used it on 4 jobs and never had any issues. I find it has a quick heat up time as pipes are right under floor covering and no slab has to be heated.and either tiles or timber flooring go directly on. Check out the price first though!

johnnyjoseph

Hi.
Thanks for opinions. It looks like the system is holding pressure thats about 3 times normal working pressure. Do you think this should be a good guarantee that all leaks have sprung at this stage?

wildefalcon

If that's dry, then that fine.

I presume you'll be using an inhibitor in the system every year, it might be a good idea to put in a can of system leak prevention at the same time.

I've had a pin hole leak in my (radiator) system for years, and a can of "stop leak" fixed it.

G.

heinbloed

Hi.
Thanks for opinions. It looks like the system is holding pressure thats about 3 times normal working pressure. Do you think this should be a good guarantee that all leaks have sprung at this stage?

No.

The impact of temperature isn't checked so far. Movement with expansion and contraction will very likely cause further leaks.
The material itself had been under stress with the freezing, including it's surrounds, the slab. Overstressed beyond it's guaranteed parameters.
Once demaged a temporary re-sealing might be achieveable. But that is nothing to rely on in the long term.

jeepers101

I agree with the above. Also you'll have no comeback if it starts leaking in 5 years. Get it replaced now while the builder is liable.

Outkast_IRE

he should get a agreement drawn up with the solicitor to state he accepts liabilty in any further leaks in the underfloor sys for X amount of years that way your covering yourself

jeepers101

And if he goes bust?

johnnyjoseph

heinbloed wrote: »

No.

The impact of temperature isn't checked so far. Movement with expansion and contraction will very likely cause further leaks.
The material itself had been under stress with the freezing, including it's surrounds, the slab. Overstressed beyond it's guaranteed parameters.
Once demaged a temporary re-sealing might be achieveable. But that is nothing to rely on in the long term.

Heinbloed, the heating has been on for approx 2 weeks now, since the leaks in the pipes were replaced. Last pressure test was completed within the last few days. Do you think this enough to check for defects that may appear due to temperature?

heinbloed

Johnnyjoseph wrote:

Quote:
Originally Posted by heinbloed
No.

The impact of temperature isn't checked so far. Movement with expansion and contraction will very likely cause further leaks.
The material itself had been under stress with the freezing, including it's surrounds, the slab. Overstressed beyond it's guaranteed parameters.
Once demaged a temporary re-sealing might be achieveable. But that is nothing to rely on in the long term.

Heinbloed, the heating has been on for approx 2 weeks now, since the leaks in the pipes were replaced. Last pressure test was completed within the last few days. Do you think this enough to check for defects that may appear due to temperature?

I'm no expert.

I, as a consumer, would stick to the legal options mentioned by the other posters. A leaked system which had been overstressed-used beyond it's guaranteed parameters- has lost it's guarantee. Whatever the next aproach of the installer might be: ask for an unlimited guarantee.

On the technical issue:

If the heating was run for two weeks - maybe it will hold. But maybe not. Was it stressed, used for a long term beyond it's design parameters? Higher pressure, higher temperature? More than the expected full load at maximum demand?

If yes and it was my own design/installation in my own home I would go for it.
But if it was for a client who might put expensive furniture onto a (maybe soon to become a damp) floor, like hand woven carpets, works of art: no.

There isn't much water in an UFH, a small leak would let out overpressure but holding the rest of it. So not much risk of a flooding, provided the filling loop is removed.

There are contracts of guarantee where a smaller demage would have to covered be by the consumer and only larger cases are an insurance/seller's case. Maybe that could be an option ? But contact an insurance broker, a solicitor for the legal part of back-up. Architects and civil engineers might be able to point you into this direction as well.

Once the worst case scenario is manifested it would get expensive: ripping out the floor, paying for a temporary accomodation, storage of goods etc..
Installing UFH costs more money than standard radiators, not only because of material and workmanship.

My hart is with the consumer, but logic could be a method to satisfy both parties.

Outkast_IRE

jeepers101 wrote: »

And if he goes bust?

if he goes bust hes screwed anyway , same with if any of his suppliers or tradesmen goes bust hes screwed . If we had to worry about everybody goin bust no business would take place at all