Far too few homes are built in a way that suits elderly people, a housing lobby group says.
Lifemark, which is connected with CCS Disability Action, said the elderly made up a growing portion of the population, but just 2 percent of new houses were designed to cater for the frail, the elderly or young people with disabilities.
Its general manager, Geoff Penrose, said to make up for this deficiency, at least 8000 age-friendly homes should be built each year for the next 10 years.
"We need to think about who is going to be living in the homes and what their needs are, and we have got to build the right type of homes for these people."
ACC recorded 359,788 falls in the home in the year to June, some of which would be by elderly people. Continuing claims from previous years pushed total accidents to 435,807, which cost the public workplace accident insurance company $434,657,873.
Mr Penrose said houses often lasted more than 100 years and, in that time, all kinds of people would live in them, including the elderly.
His organisation certified homes with features such as better lighting and non-slip surfaces to deter injuries such as falls.
However, the Institute of Architects said future-proofing all houses for elderly occupants might cost more money than it was worth.
Its president, Christina van Bohemen, said elderly people needed homes that were safe, but it would be more efficient to target improvements on homes where and when they were needed, rather than acting universally.
She said more homes could be built in a way that could be converted later on.
But Master Builders Association chief executive David Kelly said it was cheaper to build a house with age-friendly features in advance, rather than retro-fit them later.
The country had an ageing population so the problem must be dealt with, he said.
"From a health perspective it is much better and more cost-effective for people to stay in their own home than having to move into residential care," Mr Kelly said.
The Ministry of Business Innovation and Employment said more retirement villages were being built, with consents running at 1900 units annually in the latest figures, up from about 100 25 years ago.