TheScullster wrote:
"Phil" wrote

"If you can insulate the pipes in any way, the water will stay hot &
the wall not...."

Nice idea Phil, but this will mean chopping a significantly larger channel.
I am reluctant to do this, as the route passes close(ish) to a window
opening.

Having said that, I have some offcuts of heat resistant matting only about
2mm thick (used to put on the dining table under the table cloth for
protection) - should be able to make room for that.

Good call

Phil


with copper, even a few mm of styrene or depron will make a huge
difference. And even with plastic barrier type pipe.

Since plastic in screed is what my UFH does, I can assure you its a
pretty poor way to transfer heat! Even with 100m of pipe the water going
in at 50C is hard put to come out much less than 40C!!!

So I would not worry at all. Plastic in conduit sounds pretty good.