This calculator gives the heat requirements of new homes built to meet the improved standards of insulation laid down in the 1990 Building Regulations (i.e. wall and floors, U = 0.45 W/m ² K, and roofs, U = 0.25 W/m ² K). It also uses lower air change rates associated with the improved draughtproofing of modern housing.
The reverse of the calculator gives radiator, boiler and pipe sizes in addition to the above and may be used for complete installation design.
Size: 7.5/8" dia. complete in case with instruction booklet.