England and Wales: before 1900
marketed sale
Average thermal transmittance 0.30 W/m-¦K
Average thermal transmittance 0.25 W/m-¦K
Low energy lighting in all fixed outlets
Average thermal transmittance 0.16 W/m-¦K
Boiler and radiators, mains gas
From main system
mains gas - this is for backwards compatibility only and should not be used
Room heaters, mains gas
High performance glazing
Programmer, TRVs and bypass
marketed sale
Sandstone or limestone, with internal insulation
Solid, insulated
Low energy lighting in all fixed outlets
Pitched, 300 mm loft insulation
Boiler and radiators, mains gas
From main system
mains gas (not community)
Room heaters, dual fuel (mineral and wood)
Fully double glazed
double glazing installed during or after 2002
Time and temperature zone control