Plumbers please. Can I safely bury plastic water pipes in concrete?

I am replacing 3 failed 15mm copper water pipes in my kitchen. They are the hot, cold softened and cold hard water supplies to the kitchen sink. The cold pipes are under mains pressure and the hot is fed from a loft tank so there is about 25 feet of pressure.

The copper pipes were buried in the concrete floor when the kitchen was extended in 1993. They had been wrapped in hessian or similar stuff but it looks like the lime or acids or whatever in the concrete has got to the copper as they have failed over 14 years.

There is no other sensible route for the pipes so I have dug the floor up to repair them and I am considering using 15 mm plastic pipe rather than copper. The total run is about 3 meters and they will be about 3 or 4 inches under the floor. There will be no joints underground. I will connect the plastic pipes to the existing copper pipes at both ends with push fit joints.

Will the plastic pipes be ok in concrete or should I protect them?

I am thinking of various options. I could run them inside 22mm copper or inside plastic barrier pipe or wrap them in a protective layer of some kind.

Alternatively I could surround them with sand and then concrete and screed over the sand.

I want to do a proper job that will outlast me as I don’t want to be digging the floor up again in 15 years time.

I will be putting the push fit joints in easily accessible places so future replacement will be easy if they ever leak or fail. A friend of mine, who is an unqualified but experienced DIY plumber said he was initially sceptical about them but has used them without any problems.

Your informed comments and advice would be welcome. :)


This discussion has been closed.
Latest MSE News and Guides

Did you know there's an MSE app?

It's free & available on iOS & Android


Regifting: good idea or not?

Add your two cents to the discussion

MSE Forum

Energy Price Guarantee calculator

How much you'll likely pay from April

MSE Tools