Good to see you posting Burnsy ! 
Same here. We've had it on for about an hour and a half in the morning and then put the gas fire on in the evening for a couple of hours. Despite loft and cavity wall insulation the house does struggle to retain heat. This morning before the central heating came on it was 16.4c in the front room. With the 90 minute burst of heat it reached 22c but as soon as it went of at 08.15 but loses nearly a degree an hour. currently in the front room its 20.1c. In an hour or so it will start to feel chilly again.
A general question what is the normal rate of fall for a well insulated house when outside temps are around 10c and the breeze is moderate ?
Originally Posted by: Gusty
Depends how damp the walls and loft are. Damp surfaces conduct heat, dry ones don't (the reason you feel cold in wet clothing).
As I understand it, the cavity is there in the wall for a reason, particularly in coastal areas, where horizontal rain can penetrate house walls. Moisture is supposed to run down the cavity and exit at the base of the wall, below floor level. The airflow in the cavity keeps the wall dry.
If you fill the cavity with insulation, then rain from the outside and condensation from the inside penetrates through the bricks and soaks the insulation. The moisture can no longer escape, and because there's no longer an airflow the result is a damp wall which conducts heat out of the house.
Loft insulation, which prevents heat rising into the attic, can also become wet with the resultant condensation, with a similar outcome.
2 miles west of Taunton, 32 m asl, where "milder air moving in from the west" becomes SNOWMAGEDDON.
Well, two or three times a decade it does, anyway.