Leaking Pipework under floor

[verdigrey]

Morning all ,
I could do with some advice please . We were asked to find a leak in a sealed system . Big 2 story house . Oil boiler , about 24 radiators . Has been gradually loosing pressure for about a year .
We went there yesterday and isolated the top floor , and dug down and isolated and pressure tested the further half of ground floor and o.k.
We pressurised the first part of the ground floor with the boiler filling loop to about 2.5 bar and listened .
The floor is tiles on concrete , we heard the leak just under a tile so we broke up the floor and found the pipework , 2 , 28mm flow and return and along side 4 , 15 mm pipes , all wrapped in Hair felt .
Any way we found several small holes in the 28mm copper pipe . i guess that was caused by cement eating thru the pipe ? The pipe was black , which I guess means that it has been wet for a long time .
Forgive my rambling , but my question is . Is it best to replace with copper again , but try and protect it better , before re concreting . There is about 30 - 40 mm of conc above pipes then tiles . I have seen copper pipe with a plastic coating ,but dont know if that is suitable . Maybe create some ducting out of wood , with a ply top and tile over that ?
Or replace it all with plastic pipe in conduit and concrete over it all . or another way ?
Any thoughts gratefully accepted .

 

[Sparkgap]

If possible I'd look at proper floor ducting so you can get at them later and have insulation on them, if not then plastic and conduit would be a good idea, certainly for the smaller pipes.

https://www.contourcasings.co.uk/pr...emperature/lst-radiator-guards/floor-ducting/

 

[verdigrey]

hi sparkgap , thanks for your reply . Do you know if I put pipes in ducting , topped with ply . Then layed ceramic tiles , will the tiles sound hollow when they are walked on . the cust may not like it .

 

[ShaunCorbs]

hi sparkgap , thanks for your reply . Do you know if I put pipes in ducting , topped with ply . Then layed ceramic tiles , will the tiles sound hollow when they are walked on . the cust may not like it .

plastic coated pipe or if you can (straight) put the pipe in waste pipe

 

[Stanios]

Ive recetntly had to locate and fix simular type of leak, ground floor concreted and tiled ch pipework. Ended up chasing whole hallway. Had pinprick on 22mm pipe whole run was wrapped in denzo tape still concrete must have gotten through somehow.

I think concreting in pipe is just bad practice, screed maybe more suitable?

 

[Sparkgap]

hi sparkgap , thanks for your reply . Do you know if I put pipes in ducting , topped with ply . Then layed ceramic tiles , will the tiles sound hollow when they are walked on . the cust may not like it .

Yes, I expect it would sound hollow if you're dancing on it in your stilletto heels! :smile:
The other option that has been mentioned is the plastic pipe-in-pipe systems, there are several on the market.

 

[verdigrey]

Thanks Guys , We will prob go with the Pipe in pipe option .

 

[plumben]

Create a duct in the floor lag all your pipes, fill the rest of the box with Insulation, ply the top then screed over that