Water regs for pipes under concrete slab

[Yorkie79]

Hi,
I have a question about water regulations. Earlier this year we had a suspended timber floor in our front room ripped out a concrete slab poured. As a result, the water pipes coming into the building are now beneath the slab. The builder who laid the slab put some ducting in should we want to replace the water pipes in the future. I've read that the regulations say pipes should not be laid beneath the slab, but does this apply to pipes that are already there? I mean, has my builder followed the regulations or should he have laid new pipes through the conduit rather than leaving the old ones as they are?

 

[PhilGS]

I'm not up to speed on the latest regs, but the supply pipe up to the house boundary used to have to be at least 75-cm deep for protection.
There must be many water supply pipes buried under drives etc.
However, you are responsible for any problems so not a great idea to bury under a concrete slab.
The good thing is that the builder had the good sense to put it in ducting, and even better sense if he/she left you a draw string.
Existing pipes become your responsibility too.
You didn't say what material the pipes, new or old are made of.
Blue HDPE is as tough as old boots.
Copper is the most likely to damage depending upon the water quality and how good any joints are. Even brand new copper can get corrosion leaks if the water is on the alkaline side
The John Guest Speedfit pipe is pretty tough as well.
As a general rule, you really need to be able to get at pipes and any joints etc.
My HDPE is very definitely beneath the concrete, in ducting and with a responsible developer and a good plumber on site, it must have met with the Byelaws Inspectors approval, assuming they looked.

 

[CBW]

If it’s in ducting and 4” or larger should be ok. Regs state that the pipe must be able to be withdrawn to be examined if required. There’s other regs too like depth as mentioned.