Common modifications

Some 1970s houses remain in original condition, though many have been modified.

Common modifications range from major renovations to increase living space or improve indoor/outdoor flow, to smaller changes such as replacement of kitchen and bathroom fittings.

Enlarging to meet modern needs

The speculative houses built during the 1970s were relatively small compared to the average house size of the 1990-2000 period, typically having a single, open-plan living, dining and kitchen area, three bedrooms, one bathroom and a laundry. The average floor area of new homes was 107 m2 at its lowest point in 1975.

Modifications are likely to include one or more additions where the section is big enough to increase the living spaces; create some separated living spaces such as a family room or a second living room; and create additional bedroom(s), and/or bathrooms.

Some houses on sloping sites have had basements added, and these may have been used as bedrooms. Often they smell damp and musty, due to rainwater drainage not being properly addressed, and lack of effective damp-proofing, insulation and ventilation.

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Outdoor living

Though 1970s houses often had patios, decks or terraces, these were often poorly orientated for sun, views, privacy and wind direction. Some may have been modified to improve orientation. Modifications may have also provided more indoor/outdoor flow, or increased the size of these outdoor living areas.

Where existing decks are more than 1.0 m above the ground and not part of any alteration work, upgrading the existing safety barriers to meet the requirements of Building Code clause F4 Safety from falling is considered good practice. New deck construction will be required to meet the current Building Code performance requirements.

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Kitchens and bathrooms

While many 1970s kitchens and bathrooms retain their original layout, in most cases new fittings and appliances will have been installed.

In kitchens, these may include adding a range hood, installing new appliances such as a dishwasher and microwave, installing new bench tops, and changing  wall and floor finishes. Though original joinery units are likely to remain in good condition, in some kitchens new joinery may have been installed.

In bathrooms, new fittings (such as a shower cubicle and a hand basin or vanity) may have been installed, and others such as the bath, toilet and cistern may have been replaced. New  light fittings, extractor fans, heated towel rails, and extractor fans may also have been installed. Wall and floor linings and finishes may have been replaced.

Original low-pressure hot water systems may also have been replaced.
See kitchens, bathrooms and laundries for more detail.

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In some houses, original timber or aluminium windows may have been replaced. Where original windows remain some maintenance work may have been carried out. In some cases where owners have not wanted to leave windows open, positive pressure ventilation systems may have been installed.
See windows for more detail.

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Insulation was not originally installed in most houses built before 1978 but may have been retrofitted in ceilings and subfloor spaces. See insulation for more detail.