Auckland's urban sprawl is slowly growing as new homes are being built largely on its rural borders, but growth is lagging behind some rapidly growing regions.
Housing stock in Auckland has increasing by 4.7 per cent, or 15,676 new homes since 2010.
Figures given to the Herald by homes.co.nz indicated this was concentrated in the outlying areas. Silverdale saw a more than 90 per cent increase in new-builds, Karaka was 76 per cent and Stonefields 75 per cent.
Homes.co.nz chief marketing officer Jeremy O'Hanlon said these figures indicated most of the city's growth was concentrated on the "fringe suburbs undergoing development" as a number of large-scale developments, such as Millwater and Karaka Lakes boosting supply.
Growth in the central city suburbs on the other hand was slower, where less than 4 per cent of stock has been built since 2010.
O'Hanlon said Auckland's growth was "not fast enough" to meet the need for more homes and was slow in comparison to areas such as Hamilton and Tauranga, which was growing at almost double the rate of Auckland - 8.6 per cent since 2010.
Christchurch's rebuild was also going strong, with 7.8 per cent of new builds since 2010. But lagging behind are Dunedin on 3.2 per cent, Wellington, 2.7 per cent and Rotorua 0.4 per cent growth.
Nationally figures from Homes.co.nz showed development was happening on rural areas - the Selwyn district had 39.5 per cent new-builds, Waimakariri had 24.7 per cent and Queenstown-Lakes District 18.1 per cent.
And figures this week showed home-ownership was at its lowest point in 66 years, with only 1.2m of the 1.8m owner-occupied. One expert said it was only going to get worse if nothing was done.
The New Zealand Initiative's senior fellow Bryce Wilkinson said the solution was a "no-brainer" and lay in freeing up land for greater residential development.
In 2016 QV costbuilder data indicated the cost of building a new home had risen 2.4 per cent and could cost up to $4525/sq m, plus the associated additional costs in getting the land prepped for a new home.
Percentage new builds
Auckland 4.7 per cent
Christchurch 7.8 per cent
Wellington 2.7 per cent
Dunedin 3.2 per cent
Rotorua 0.4 per cent
Selwyn District 39.5 per cent
Waimakariri 24.7 per cent
Queenstown-Lakes 18.1 per cent
Hamilton 8.6 per cent
Tauranga 8.6 per cent