Cowboys in the construction industry are being targeted by a bill that will introduce fines of up to $200,000 for jobs done without the proper paperwork.
The Government is aiming to make building contractors more accountable for their work by making companies or individuals provide upfront evidence of their skills and track record, and insisting that they fix any faults quickly and efficiently with no questions asked.
The changes would also affect do-it-yourself renovators.
The Building Amendment Bill (No 4) is part of a review of the Building Act prompted by the $22 billion leaky building crisis. It passed its first reading in Parliament on Tuesday, but several MPs expressed concern that the amendments left the building industry to police itself.
At the bill's first reading Building and Construction Minister Maurice Williamson said the proposals gave consumers more protection when building or renovating their homes.
If it was brought into law, builders would have to provide a comprehensive document that informed a client about the people who would be doing the work, the company's profile, and proof that it could cover the costs of fixing any faults.
If a builder made an error, the principal contractor would have to fix it within a year.
Mr Williamson said: "The 12-month period is intended to be a 'no questions asked' requirement for the building contractor to stand behind the quality of their work, similar to how faulty goods can be repaired if they are not fit for purpose.
"We can do it for colour TVs, we can do it for our new motor cars, so we should be able to for new buildings."
Contractors doing more than $20,000 of work would have to sign a document with the homeowner, and the maximum penalty for doing work without consent would be doubled to $200,000.
The amendments to the Building Act would also give more power to councils to deal with non-dangerous buildings that were near or adjacent to dangerous structures.
The amendment was influenced by experiences during the Christchurch earthquakes, and would allow councils to prevent people from entering buildings close to dangerous structures.
The amendments have been supported by National, Act, the Maori Party, Labour and Greens but New Zealand First MP Andrew Williams opposed it at the first reading because he felt it reduced the role of local government and left the industry to police itself.
"If there are unscrupulous people handling that, and builders who can create companies and close them down as quick as anything, we could end up with the same situation as leaky homes, where no one can find the person responsible," Mr Williams told the Herald.
Labour and Greens also expressed concern that some of the new rules amounted to deregulation.
Labour housing and construction spokesman Phil Twyford said the Government also needed to address some wider issues including the under-investment in building apprenticeships.
* Any building jobs over $20,000 will require a written contract.
* Building contractors have to provide disclosure statements on their qualifications, track record, skills and licence status.
* Principal building contractors must fix defects within 12 months.
* Maximum penalty for building consents raised to $200,000.
* New powers for local authorities to deal with non-dangerous buildings close to dangerous buildings.