Laying copper pipe in concrete floor

[Ratter]

I need to move a radiator and perhaps extend the system down a long hall with one cold (unheated) end. The floor is concrete and the obvious answer is to channel the floor using an angle grinder or similar and lay the (15mm) pipes in that.

I have been told that laying pipes in concrete is not advisable because the alkaline concrete will corrode the pipes. I am thinking of filling round the pipes with plaster because pipes are often buried in plaster walls. Is this a good idea? Would I need to wrap the pipes and if so with what?

Alternatively, is there a better solution? I don't like using plastic pipes but is this where they come into their own?

Great forum by the way

 

[kevplumb]

plaster is as bad as concrete WRAP THEM

 

[ChrisR]

If you don't give them room to move, the joints will pull apart.

This is one way:
http://www.bes.ltd.uk product 16538

 

[cross thread]

i would use plastic,no joints. make the chase big enough to allow for a bit of movement and bed/cover with sand to allow for movment

 

[chrishutt]

Run 10mm plastic pipes in a sleeve (flexible conduit or even 15mm plastic pipe), then the pipes could be withdrawn and replaced if there was ever a problem.