Auckland's Deputy Mayor said the council backs every new housing development - and the Government's latest promise is no different.

Building is set to start on three crown land sites in the city, with 740 new homes to be on their way up.

Most will be apartments, with 150 homes to be 'affordable' housing, and 150 more to be used as special housing.

Penny Hulse said it's totally up to the Government to develop its crown land how it sees fit.

"They're quite within their rights to develop more affordable housing and more social housing if they wish, and obviously we'll be watching very keenly to see if they choose to do that."

However, it will be over 18 months before anything is constructed.

Ms Hulse said anyone who's gone through building a home knows it takes a long time, and it's frustrating.

"What we really need are more people trained in the industry, we need more capacity in the building industry, and we need the Government to assist with some more funding to actually get this happen."