Housing Minister Phil Twyford has apologised for a mistake he made about the price of a KiwiBuild home.

On Friday morning on The AM Show, Mr Twyford said the price of a one-bedroom Kiwibuild home would be $550,000.

That's $50,000 more than a document sent out just two days ago by the Ministry of Business, Innovation and Employment (MBIE), which said the homes in Auckland and Queenstown would be priced at $500,000.

Mr Twyford now admits he was wrong.

"I misspoke this morning when discussing the KiwiBuild price points. I apologise for any confusion caused," he said in a statement to Newshub.

Mr Twyford was asked repeatedly what the price point was and the minister said $550,000. He was given the opportunity to correct himself when host Duncan Garner asked "Wasn't it $500,000?"

"Yeah, it's gone up slightly. We did the original modelling for those price points two years ago, and under Judith's [Collins, National housing spokeswoman] Government's policies, build costs are rampant," Mr Twyford told The AM Show.

Newshub asked to speak to Mr Twyford so he could clarify, but he instead sent a statement. He was adamant this was down to a scheduling issue.

"I am not refusing to front for Newshub; in fact I dedicate every Friday morning to appearing on your AM Show.

"Unfortunately I am unavailable because I have back-to-back meetings in Auckland today with people building houses."

Labour's KiwiBuild policy before the election was that standalone houses in Auckland would be priced between $500,000 and $600,000, and apartments would be priced $500,000 or lower.

But the tender documents show that's now changed. All new homes built under the policy will now be costed by room.

One bedroom will go for $500,000, two bedrooms $600,000 and three bedrooms $650,000 - that's $50,000 more than Labour promised in the election.