New concrete floors - When to fit plumbing?

[thompo]

Hello

In the process of renovation and we are replacing the existing floors with concrete and underfloor heating.

As we are replacing the floors, all the existing pipe work has been removed.

We are at the stage now of filling and compacting the floors ready for concrete but are wondering when would be the best time to fit things such as waste pipes for sink/shower etc? The toilet is going to stay in the same place so we wont be needing a new soil pipe hopefully.

Would these normally be ran under the slab with upstands to connect to? Through the insualtion? or over the finished floor and out?

As for the water/radiator pipe work, ive been told to run through the insualtion below the UFH pipes? Is this common practice or is it better to go around walls or drop down from above? Just thinking for ease of maintence should anything happen it will be eaiser to fix rather than dig up screed whilst dodging UFH pipes.

Thanks Neil

 

[dcawkwell]

Wouldn't use concrete floors and wouldn't use underfloor heating.

Suspended wood floors are much nicer and radiators respond much faster.

As you point out anything that is wrong it's a big mess to sort out.
Wood floors it's easy.

 

[Dan Robinson]

Sorry bud but that is complete twaddle.

Once it is in, and in properly the chances of there being a problem are pretty minimal - just make sure it is pressure tested fully before putting the concrete in.


UFH too, in a well insulated property with the right controls is also excellent. Granted it isn't going to heat the room in half an hour, but then it isn't supposed to - so using that as a comparison isn't really fair.

 

[Nige F]

Hello

but are wondering when would be the best time to fit things such as waste pipes for sink/shower etc? The toilet is going to stay in the same place so we wont be needing a new soil pipe hopefully.

Would these normally be ran under the slab with upstands to connect to? Through the insualtion? or over the finished floor and out?

As for the water/radiator pipe work,
Thanks Neil

Keep both lots above the floor - just have the UFH pipes , er under the floor

 

[Agile]

Most builders just bury plastic plumbing pipes in the concrete/insulation. They dont have to deal with maintenance.

DIYers sometimes go to great lengths to fit single lengths of plastic pipe in duct tube in the expectation that if there were any problems they could pull it out and draw in a new length.

The reality is that with properly fitted and specified plastic tube there is unlikely to be any problem. At least not for 10 years +

Its a much larger debate over the advantages of slow heat up UFH compared with fast heat rads!

Some of the aspects to be considered are:-

Significance of heating costs.

Signification of instal costs.

Regularity of occupation e.g. teachers or policeman

Desire ( like me ) to be cool at night.

On 31st dec I went to a small party at a friend who has fitted all UFH with 26 zones. It was amusing to see the overheating problems caused by the UFH as the room filled up with 30 people and even more so when they started dancing. Not helped by his Aga which seemed to be providing about 2 kW of heat!

Tony

 

[Norcon]

As your in NornIron the sub floors are laid over compacted stones.
Might be radon barrier to go down or plastic film depending on whats specced.
Then you lay all plumbing pipes for h&c water, secondary return, supplementary rads, towel rails and drainage runs also. Keeping them as straight as possible and grouped. 50mm is best for drainage! And internal 110mm outlets if possible.
All pipeworks needs pressure tested and all pipes need insulated.
In England they put the insulation below the sub floor which is more inefficient btw as it increases heat loss.

Then lay floor insulation, then lay ufh pipes.
Its worth pricing a liquid screed as its becoming more competitive.
Which will give a faster response on heat up.