I am considering installing UFH in a bathroom, the arear to be warmed
is 8 square meters my plan is to run the boiler flow pipe (22mm) to two



zone valves one of which runs the whole houses radiators and the other
is to run to the bathroom in 22mm where it is reduced to 10mm JG
speedfit for the UFH loop and back on to the 22mm return to the boiler.



The boiler is Worcester 28i junior (non condensing) and brand new.


after the pipes are in it is to be tilled


My question is by reducing it to 10mm will this provide sufficient heat



restriction so as I dont have the full heat of the boiler on the floor
tiles?


i.e. I dont want to cause them to crack through thermal shock.


I am not a qualified plumber but have a few years of experience in
domestic systems

Follow up


I am informed that thermal shock is possible they are ceramic and 11mm
thick as for the controls i was thinking that a radaitor valve works on

the principal of closing the lock shield slightly there by reducing the

flow, that is my reason for using 10mm pipe ie the reduction from 22mm
to 10mm would severly reduce flow and temperature.


I could very well be wrong! but i hope not.


Thanks for any advice


Martyn