Adding radiator to existing system
Is flomasta speedfit barrier pipe and fittings suitable to use to add a radiator to existing central heating system. I just had a plumber out to add a radiator in the loft, which had to have the pipe run from the loft down through the ceiling to connect to the original pipes under the upstairs landing floor. I thought he was going to be using copper pipe but he never, he used the plastic. It wasn't the best job, for example pipes with elbows on hanging down from the ceiling by a few inches not clipped and a couple of other issues like the fittings not closed properly, you could still see the green indicator on them and a couple of issues with the pipe clips, along with an elbow nearly popping off at the top of the ceiling because the pipes heating up bent the pipes coming down the wall that much that they sagged, pulling the pipe downwards because they were not clipped correctly, and the connection on the elbow was pushing down on the edge of the wall clip and he hadn't put any collet clips on to stop it pushing off. This happened after just an hour and a half of the heating being on, I'm concerned about when the heating is on constantly in the winter. The way the pipe heats up and sags and the constant hot water going through the plastic fittings concerns me. He said that it is standard practice to use the speedfit instead of copper now. After reading a lot of reviews on the flomasta stuff I am now worried because a lot of plumbers are saying that it is no good and over time the fittings leak and obviously cause major damage to the property. The pipes and fittings will be concealed in a wall which will not be accessible and also under the landing floor. I contacted the plumber over it and mid conversation he said all that he would do is tighten the connections or give me a quote to redo it in copper, ended the call and won't reply to me now. So I have tightened up the connections and added a few more clips where I can, but can't secure the ones hanging out of the ceiling and also put collet clips on all fittings.
Do you think it will be okay or is this stuff not reliable. Or do I need to get it changed to copper, I just had to borrow the money to get that done?
Thanks in advance
Advice from 2 local tradespeople
The short answer is: plastic barrier pipe and push-fit fittings can be suitable for adding a radiator to a central-heating system, but your description sounds much more like a poor installation than a material problem. Both Flomasta barrier pipe and JG Speedfit barrier pipe are sold as suitable for central heating, and Speedfit’s technical data states that its fittings for central-heating systems can handle high temperatures, with the barrier layer intended to reduce oxygen ingress and corrosion.
What worries me in your case is not “plastic instead of copper.” It is the way it was fitted:
vertical drops left hanging out of the ceiling,
sagging when heated,
fittings not fully locked,
poor clipping/support,
and elbows under strain.
That is not what a good push-fit installation should look like. JG’s own guidance recommends collet clips/covers where fittings may contact rigid surfaces or sit behind dry-lining walls, and Flomasta/JG installation guidance also requires proper pipe preparation, full insertion, and support/clipping.
On the green indicator point: if these are the Flomasta twist-lock style fittings, the installation instructions say the green band is visible when the securing nut is loose/open, and after tightening the securing nut, the green band should be hidden. So if you can still see the green indicator, that strongly suggests the connection was not fully locked in the intended final position.
Regarding the lack of inserts and clips: Flomasta’s pipe instructions state that inserts must always be used with Flomasta PB or PEX pipe in Flomasta fittings. And JG guidance says collet clips are used to prevent accidental disconnection, especially in locations like behind dry-lined walls. So your instinct was right to be concerned about unsupported fittings and unsecured joints in concealed areas.
So, is the stuff itself unreliable? I would not say that. Properly installed barrier pipe/push-fit systems are widely used and can last for a long time. Would I be happy with the installation you described, concealed in a wall and under a landing floor? No. That is because fittings under mechanical strain, pipe sagging on warm-up, and incompletely locked joints create leak risk regardless of brand. That last point is an inference from the manufacturers' installation requirements and the symptoms you observed.
My practical view:
You do not need to have it all ripped out just because it is plastic.
You do need the installation checked and, if necessary, reworked by a competent plumber.
At minimum, I would want:
every joint remade and fully locked,
inserts confirmed in every plastic-to-fitting connection,
proper clipping/support added,
no fitting left under sideways strain,
and any concealed push-fit joints secured exactly as the manufacturer requires.
If you want the most robust outcome, a sensible compromise is often copper for the exposed drops and final radiator connections, with plastic only where it is well-supported on longer hidden runs. That is a judgment call rather than a rule, but in your case, it would reduce sagging and improve appearance while still avoiding a full re-pipe. The key issue is still workmanship, not the use of plastic at all.
My recommendation would be: do not leave it as-is and hope for the best. Get a second plumber to inspect it soon, take photos now, and ask specifically whether the joints are fully locked, whether inserts are present, and whether the unsupported sections should be remade. If they confirm the current run is under stress or unsuitable for concealment, I would have those sections redone rather than wait for winter.
Yes, Flomasta Speedfit (JG Speedfit) barrier pipe is suitable for central heating, but the installation was faulty, leading to your issues; you need it re-done correctly with proper support and inserts, or changed to copper if you're uneasy, as badly fitted plastic can fail, but it's a standard material when installed right. Your experience highlights poor workmanship (no clips, visible indicators), not inherent material failure, but since pipes are hidden, getting it fixed by a competent plumber or changing to copper for peace of mind is crucial to prevent major damage.
