100% double-glazed
30c combi-boiler with all recent radiators
No drafts
Front (double-entrance/porch) has a draft seal all round and double-glazed.
Rear room, hallway, stairs and landing are wooden-floored but no gaps.
The living room- v.thick underlay and thick carpet yet its the coldest room.
The loft is insulated (checked)
The walls are pre 1930 brick and we've been told cavity wall insulation isn't possible.
Warm if you keep heating on however literally as soon as it goes off the house is freezing which says to me the house is very inefficient and shouldn't lose heat that quickly. Really scratching my head here.
Anything I can do?!!!

