Copper pipes in floor/compound

[Bert]

Hi all,

My house has Copper pipework (Central heating & Gas) laid in the concrete floor. Not at the time the floor was laid I might add. The concrete has had small trenches cut out and the pipes laid in to them and filled with some compound? Can anyone tell me what this compound might be?, and if it is appropriate for the job (if not any suggestions for alternatives)? The compound is like a very course carlite bonding consisting of particles about the size of pea shingle. It is light grey (when cured) and very brittle and light weight.

I need to do some work altering the pipe work (I am looking forward to trying to get the water out of them pipes :o( ) and I then will need to make good the floor. My instinct would be to use a concrete mix to fill it in but the pipe work is not deep enough to allow it to be covered with Denso tape for protection in the concrete.

Advise much appreciated.

[John]

I would have thought that a levelling compound like latex screed might do the trick for this sort of thing. I'm not sure what sort of effect it would have on pipes; but I can't imagine it would be bad for them.

john

[Ken]

Sounds like they used Vermiculite, I think that's how you spell it. You cover the pipes with it and then screed the last 2". I don't understand why you say the pipes are not deep enough to cover them with Denso tape. Are you saying the top of the pipes are level with the screeded floor?

ken

[Bert]

Ken,

I must admit it does look like Vermiculite that you find on the gardening programs but I didn't think that cured?

The tops of the pipes are only a few mill below the top of the floor in many places. Denso that I have used before is a few mill thick so would like to avoid using it if possible. As the pipes are mostly round the edges of rooms they are ot subject to foot traffic so strength is not paramount, just a level surface.

Thanks

[Ken]

Vermiculite was used exstensively in the 1960s as a floor insulation. It was spread over the concrete or block floor and then the usual screed was laid on top.

ken

[TonyB]

I understand that direct contact between concrete type materials will allow acid to eat away the copper. Hence the insulation. When I did my oil pipes I ran them inside a plastic conduit and then concreted over that. They've been OK now for 15 years. TonyB