A Nelson couple left with a leaky bathroom in their new home say the building consent process is not worth the paper it is written on.

Their comments come as the government considers cutting red tape by allowing builders to sign off on their own work.

Photo: RNZ / Tracy Neal

Paul and Faye Gurr built their new home on Nelson's Port Hills five years ago.

They contracted a home-build firm to construct the house, but hired their own tiler. The city council's building inspectors carried out regular scheduled inspections and eventually issued a certificate of compliance.

Photo: RNZ / Tracy Neal

The Gurrs recently discovered their tiled shower leaked so badly that water had filtered through the grout to the cubicle's foundations. A repair job of up to $10,000 looked likely but everyone concerned was ducking for cover, Mr Gurr said.

"We tried to contact the tiler, who has refused to respond to us, so we got another tiler to look and he explained there was water getting underneath.

"We got the insurance company around and they said they'd only cover if it was general wear and tear and not poor maintenance, so we had to lift the tiles and that's when we saw all the grouting was done the wrong way and he [the tiler] hadn't used membrane around the side or up through the joins or wallboard."

Mr Gurr said the council had signed off the job. But, after a meeting with the council's building inspection team, he learned that - despite the $11,000 the couple had paid in building consent fees, which included about $2000 for inspections and sign-off - the failure remained their problem.

"They have told us to take it up with the tiler but I got the feeling council was stonewalling. I said, 'you were there and inspected the house and signed it off, so where is the safeguard for the consumer?'

"Basically this form that shows it has code of compliance is not worth [the] paper it's written on."

The Gurrs said they believed the council needed to step up.

Are changes to the consent process needed?

Nelson City Council building manager Martin Brown said it was not always possible for building inspectors to see work as it happened.

He said the shower had a waterproofing system applied by a licensed applicator.

"The inspector was called in to review the membrane once the tilers were ready to tile - which meant it was not possible to see exactly what had been installed. In situations like this, we have to trust trained and licensed applicators to carry out their jobs correctly.

"In cases such as these, it is acceptable practise for a building consent authority (BCA) to gain further validation by requesting a producer statement for construction from the licensed applicator, as was the case here.

"A code of compliance certificate was then issued on the basis that the BCA was 'satisfied on reasonable grounds' the work had been completed to code. The BCA took all reasonable, practical steps to satisfy compliance," Mr Brown said.

Master Builders Association chief executive David Kelly said a certificate of compliance was not a guarantee for building work.

He said, however, that while tradespeople who carried out faulty work should be the first to be held responsible, councils were not immune to legal action in such matters.

"There are several steps a homeowner needs to take if they find they've got some damage caused by building [work]. One is to get some independent technical advice.

"Secondly, they need to go back to the person who's done the work and seek to get it remedied through the contracts they've got with them, but if they're not there then the homeowner needs to get the property file - including any photographic evidence of sign-off.

"They may need to seek legal advice as to whether they've got any recourse against the council or any other party," Mr Kelly said.

Former New Zealand Institute of Building Surveyors president Philip O'Sullivan said it was preferable to keep lawyers out of the picture and, for the sake of ratepayers, it was not possible for councils to be responsible for every building failure.

He said, while the industry would be a lot worse off without the current consents scheme, the Gurrs' problem reflected the need for improvement.

He said the new proposal by the government for builders to sign off their own work was one possible way forward.

Meanwhile, Mr Gurr said his experience had left him with little faith in the process - and he has been told by the council he will need another building consent to fix the shower.