Plumbing Question

Is it common practice to use plastic pipes and push on joints in a new extenstion

I'm having a new extention built which will include an ensuite and a new combination boiler.
I have noted that the builder has used plastic pipes connecting to some copper pipes using push on connectors, also some plastic pipes are reccessed into the brickwork and will be used for a radiator. Is this now common practice? In my day it was all copper pipe. Will these pushon's withstand water pressure?

Any advise appreciated?

15 Answers

Best Answer


Plastic pipe has pretty much taken over from copper except for gas supply and pipework within a few metres of the boiler. The joints are pressure tested to well in excess of a domestic installation, somthing like 10 bar, or 100 psi. As long as they have been installed correctly and are well supported, they will be fine.

Answered 5th Aug 2011

Aztec Bathrooms

Member since 8 Mar 2011

Plastic pipes are used more and more these days, they are horrible, bulky looking things!!! so why do we (or some people) use them? you may ask.
The reason is that they speed up the installation time, hence the name speed-fit.
If out of sight and fitted correct they are fine.
If not they are poor and so is any tradesman who would use them ( in my opinion).
I only use them as a temporary fitting or in a very rare event. ie: cant get the water turned off, which means i cant solder a copper fitting.

When they was first brought in to the building trade, they was very costly but the more they are used, the price starts to come down.
As the cost comes down and the plumbers are quoting for work, there are two main items of an estimate to consider:
1 cost of goods plastic v copper
2 cost of labour speed-fit v non speed

I would ask anyone doing plumbing, what they are quoting for using.

I once fitted a bathroom for a customer who was high up in an insurance company,
I was explaining the plastic v copper plumbing and he said let me stop you there.
Our company had a meeting yesterday and the whole meeting was based on "how much money (in claims) do push-fit plastic fitting cost our company??
This left me only to say " I REST MY CASE "

Hope this is of help
Chris Devlin

Answered 5th Aug 2011


Member since 7 Dec 2009

push fit pipe is very common theese days its quicker and easier than copper. reccessing them into brick work is fine and plastering over is all ok as for holding the pressure that is no problem as long as they are put togher correctly and have used inserts in the pipe

Answered 5th Aug 2011

cheshire bathrooms and wetrooms

Member since 30 Jul 2011

I would use plastic for heating systems as it holds the heat more efficently.

I would not use plastic in the country but in town it should be fine

Answered 10th Aug 2011

Deans Heating

Member since 22 Jan 2010

Yes, usually plastic will be fine to connect up a radiator. The cheapest Plastic PEX (PolyEthylene X linked) or PB (PolyButylene) pipe and fittings can generally withstand 6 bar at 65 degrees and 3 bar at 92 degrees. The most pressure and temperature in a failure mode your will ever see on a modern sealed heating system is <90 degrees and 3bar.

Answered 5th Aug 2011

Blake Ecotec Ltd

Member since 8 Feb 2009

In a word - yes it is fine - The way I see it - if you want to cut down on the installation time and there are some long runs to be perhaps hidden/recessed then plastic is the way to go. You can cut down on the number of joints used and therefore cut down on the possibility of any leaks. That said if you can see the pipe work then copper if definitely the way to go - looks a bit smarter. Cost wise however - copper is expensive.


Answered 5th Aug 2011

JSG Plumbing & Heating Ltd

Member since 28 May 2009

Hello there is no problem with plastic pipe and push fit fitting, plastic is now much cheaper than copper.
The pipe work should be pressure tested to 10/12 bar after first fix.
The gas pipe MUST NOT be plastic or push fit fittings.
The boiler must be connected with copper pipe.
Hope this helps!!

Answered 5th Aug 2011


Member since 13 Oct 2007

Hi Jivebunny,

With cost of copper at an all time high it makes financial sense to seek an alternative. Plastic pipe is much cheaper, easier and quicker to install. I always ask the customer if they have any preference.

I understand that all pipework which can be seen should be in copper and the rest in plastic.

I have no experience of this but it has been known for plastic pipe to have been knawed through by vermin, something which would not happen with copper.


MJM Plumbing Services

Answered 4th Aug 2011

MJM Plumbing Services

Member since 13 May 2011

Yes ,normal practice now usually after one meter from boiler

Answered 4th Aug 2011

Foster Electrical & Property Maintenance

Member since 25 Mar 2009

Yes this is ok although I am not a big fan of plastic it is used throughout the building industry and is certified and as long as it is fitted correctly should last as long as copper.One point you need to check is that the plumber put clips on all the plastic joints as this ensures that the fitting cannot come lose or blow


Dave Price


Answered 5th Aug 2011

TWM Construction

Member since 12 Jun 2008

No feedback

hello it is common practise with the cost of copper the plastic will last no problems if fitted corectly
normally plastic is hidden and any pipework on show would be copper
regards luis


Answered 5th Aug 2011

java group ltd

Member since 1 Mar 2010

Yes it is common practice with the exeption of pipework within 1mtr of the boiler and all gas pipes.

Answered 5th Aug 2011

kevin cassidy building contractors

Member since 16 Dec 2010

Yes its more common now to use plastic pipes, they are safe and sound to use, if you have any concerns call Building Control at your local Council to come and check on the works to date, the Builder wont mind as he should merely be following your Architects plans.

Answered 5th Aug 2011

ATS Building Services

Member since 16 Oct 2009

Alot of plumbers have opted for the push fit plasyic in relation to copper and i think its a great option.
BUT be careful because some insurance policys will only cover copper plumbing work! talk to your household insurnace company!
I know one very well known company that installs and gives cover will not cover plastic pipework.

Good luck.


Answered 5th Aug 2011

Cannon Preservation Ltd

Member since 21 May 2011

speed fit connectors and plastic pipe are sometimes frowned upon by old school plumbers but have their uses in new builds and extensions for ease of installation. however i would NOT expect to find them on heating systems (alarm bells ringing) as i wouldnt use them myself for that purpose

Answered 5th Aug 2011

db advanced finishes

Member since 27 Sep 2010

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