Add underfloor to S-plan - S-plan+? closely spaced tees? new boiler?

[John.g]

If you run the rads with flow/returns of 55C/45C then you have a T30 rad with their outputs reduced to 51.5% of their T50 rating.

 

[John.g]

If you run the rads with flow/returns of 55C/45C then you have a T30 rad with their outputs reduced to 51.5% of their T50 rating.

Anyway, you can always increase the boiler flowtemp as required in winter so a good idea with the UFH installation without major surjery.