Existing homes

How house type affects retrofit

There are 1.6 million existing homes in New Zealand, many of which are cold, damp and expensive to run. Most need retrofitting. We’ve broken them down into basic house types and the common issues for energy retrofits for each type.

House types

Even though New Zealand’s climate varies from the top to the bottom of the country, the same basic housing types in each period of history were used throughout the country.  In the main, these were timber framed houses with metal roofs and little or no insulation.  As shifts in society and culture occurred, including updates to the building regulations, changes appear in house typology. 

The main house types are:

Early housing (pre-1890)

Ease of retrofit will depend largely on access to ceiling and floor

Art deco (1925-1935)

Likely to require moderate to considerable effort and cost to energy retrofit

1970’s housing (1970-1978) pre-insulation

Wide variation in styles and generally moderately easy to energy retrofit

Early 2000s (1996-2007) post-insulation upgrade

Daunting retrofit option. Each case must be judged on its merits.

Villas (1880-1920)

Good retrofit candidates for better energy performance

State houses and mass housing (1930-1970)

Good candidates for energy retrofit,  particularly the 50’s classic

1980’s housing (1978-1989)

Wide variation in styles and generally moderately difficult to energy retrofit

Bungalows (1920-1940)

Good retrofit candidates for better energy performance

1960’s and early 1970’s multi-unit houses

A challenge – likely to require   considerable effort and cost to energy retrofit

Early 90s (1990-1996) pre-revamped Building Code

Wide variation in styles and   generally moderately difficult to energy retrofit
ACCESS COMING SOON: What else is in the knowledge base?
  • Cost benefits of sustainable housing retrofits
  • Sustainability options for retrofitting New Zealand houses: Energy
  • Market segmentation of New Zealand’s housing stock
  • Housing retrofit: Housing interventions, stock and market