Need to get underneath underfloor heating?

[Dazswife]

Hi

Our kitchen has underfloor heating covered with a concrete screed. The house is a Potton build bungalow and the floor is apparently 'suspended'. We are having a new kitchen which includes a sink in the island in the middle of the kitchen. The main waste is about 4 meters away from the additional new sink in the island so I was hoping to be able to get an area around current waste excavated, gently remove some screed in the new area then manoeuvre the underfloor heating pipes in order to pull through some waste piping from new waste to old one then join them up! However, when trying to first excavate around the existing waste pipe it appears to be about 6-7 cm of concrete.... Can anyone advise what I may need to do. Or whether it gets thinner as I move into the kitchen? Do I need to channel the whole lot?

Many thanks

 

[KenGMac]

Dazswife, Hi.

Several points that you need to consider?

1/. If indeed the floor in the Kitchen is "Suspended" I believe that access under this floor will be a requirement, see below.

2/. You note that the waste pipe may have to be let into a channel, in the Concrete screed? I do not think this will work, because the waste pipe will need a fall. That is in general terms a 35.MM pipe will need a "fall" of 1 / 35 [One meter fall for every 35 Meters of travel] this to ensure that and solid matter in the pipe can be washed away by the accompanying water. Obviously the waste pipe that has to traverse the floor for a distance of some 4 Meters will if laid in a channel shall we say "encounter somewhere" a heating pipe ?

3/. If there is a void under the floor then the same waste pipe will need to be supported, if not it will simply form a large curve where waste water will gather and a build up of solid will lead to constant blockages. to ensure that this does not happen, someone will need to get under the floor and ensure that the pipework is clipped to the underside of the floor and has a "run"

4/. As an aside to the last, it is important that the waste from the island sink can after its 4 Meter "fall" enter the waste down pipe it is being sent to.

5/. I have just Googled "Potton" and note that this appears to be a Bespoke timber framed supplier [appears high end?] that would then explain why there is a hot water under floor heating system, not uncommon but "unusual" this could assist in that plans should be available from the title deeds or from Potton, this could assist in designing a route for this waste pipe?

6/. Odd question? has this "problem" just arisen or were any questions asked by the Installer who should have undertaken a "survey" of what was to happen and more especially how to achieve the proposed end result?

No "magic bullets" I am afraid, just questions and "observations"

Ken.