11.2 Northern Beaches, New South Wales

This case study shows how a well planned renovation has improved year round thermal comfort, reduced energy and resource consumption and lowered waste production within a tight budget. The case study showcases the principle of ‘reverse brick veneer’, one of the most effective construction techniques available.

In this renovation, the lounge room was relocated to the north and redesigned to take advantage of the site and climate. A new home office was located on the first floor away from the noise and fun of family life. As it would be occupied all day most days, it also had to be north-facing.

The remainder of the house remained untouched as it had been previously optimised. The project aim was to improve year round thermal comfort of the house, reduce its energy and resource consumption and waste production. This is commonly referred to as creating a sustainable house, although this term should be used with care as it is rarely literally true. The major constraint was budget: maximum benefit for minimum expenditure. Much use was made of found or secondhand materials and the entire project cost around $95,000.

The original house

Since its purchase in 1981, the house has been a testing ground for ideas and the subject of several on-going projects. Its rather rambling layout comprises four bedrooms, two living areas, a games room for the children and an office for the owner, who works from home.

‘Design for climate’ was not considered by the original spec. house builder when the house was built in 1962. [See: 4.2 Design for Climate] The original lounge room was located on the south side of the house, facing the street. The floor plan was a simple rectangle with a brick perimeter dwarf wall and footings. The timber framed structure with raised timber floor and concrete tiled roof was completely uninsulated.

Site and climate

The site is located on a gently rising escarpment above the northern beaches of Sydney. It slopes gently to the north east, with a stand of mature melaleucas along the eastern boundary. A large deciduous tree is immediately to the north of the house, and several medium to large eucalypts are to the west and south west. To the north east there are some ocean views.

Surrounding houses are detached bungalow houses, dating from 1960 onwards. To the north is a two storey terrace and to the south a large volume single storey house with a garden studio at the rear.

The climate is mild to warm temperate. Because the site is on the north side of a spur and within 2km of the ocean, the micro-climate is milder than the Sydney average. It is well protected from cold southerly winds, suffers no frosts and receives cooling summer sea breezes. [See: 2.2 Choosing a Site]