Question

A single-storey brick veneer house (single layer of brick on a timber frame) has a front corner lounge-room with a floorplan measuring 4.0 m by 3.8 m. The ceiling is 3.0 m high. The building fabric of the two exterior walls comprises a 12 mm thick layer of plaster, a 100 mm air gap and the exterior house bricks (110 mm thick). One of these walls has a window measuring 2.7 m wide by 1.35 m high, featuring a 3-mm thick glass pane installed in the mid-1950s. The floor is carpet over 19 mm thick pine floorboards, and the house is on stumps with a ventilated air gap between the ground and the floorboards. The ceiling is 12 mm plasterboard covered with a 50 mm thick layer of loose fill insulation in the roof cavity. This house is located in suburban Melbourne.

Estimate the cost to heat the interior of this room to 21°C all year round using a mid-level residential gas central heating system. Assume the under-floor and roof cavity temperatures are equal to the outside temperature.

Answer 1