On Fri, 9 Oct 2020 19:06:13 +0100, The Natural Philosopher wrote:

To get the house up to temperature on a cold morning make that
thee hours,

That's worse than this place, that's high, exposed, draughty and
not
overly well insulated. If it's not windy it takes about 90 mins to
reach the target temp on a cold morning. If it's windy and cold
the
boiler can barely keep up...

UFH. very very long time constant

Ah, equivalent of letting this place cool down, high thermal mass.

--
Cheers
Dave.