DIY underfloor heating - 10mm microbore

[mark.carline]

We're currently getting an extension built on the back of our house and the build is almost at the 1st fix stage (roof / windows going on in the next few weeks).

The insulated floor still has approx 25mm of concrete to go onto the top and so there is enough room for the 10mm microbore pipes for the heating system under it.

There is one area of the house which i'm tempted to lay in a coil of 10mm copper microbore pipe down (wrapped in black tape to stop corrosion etc) to increase the heating in this area and then also feed this (in series) to a radiator in the same area (so its switched off via a TRV at the same time as the radiator).

I have still yet to mention it to the builder & plumber but wanted to see what people thought here first.

Thoughts?

EDIT: - Looks like this might be a bad idea because the water in the underfloor pipework needs to be at a lower temperature than the water in the radiators.

 

[mointainwalker]

The insulated floor still has approx 25mm of concrete to go onto the top and so there

What exactly is being laid on what ? 25 mm of concrete or mortar screed as a separate layer will break-up.

 

[Agile]

If you really must do that then put in on the return from the rad.

Unless its only a short length of tube you are likely to restrict the flow rate too much.

The rad and underfloor have completely different thermal time constants so the TRV may not be the best way to control them.

Tony