Risks in unlicensed jobs
A warning has been issued to anyone seeking a plumber, gasfitter or drainlayer - check their licence or risk the consequences.
The Plumbers, Gasfitters and Drainlayers Board says many tradespeople are working without a licence, putting their clients at risk.
Master plumber Dave Strong, managing director of Morrinsville Plumbing & Gas Services, said the problem was nationwide.
Though some cases were minor, others were life-threatening.
"There's lots of it. It's everywhere. It becomes a problem when something goes wrong and the people try to see who they can come back to. Then they find they've been dealing with unregistered people and there's no-one to come back to . . . and then insurances in some cases become null and void.
"If someone connects the wrong pipe you could potentially have . . . sewage going into clean-water pipework. It's not a good look, and very dangerous to your health. If someone tries to run a gas pipe and it's not done correctly you run the risk of asphyxiation, carbon monoxide poisoning, and you run the risk of gas leaks and explosions."
He said in one case a person botched the installation of a gas hot-water cylinder, gas heater and septic tank system. "If you install a hot-water cylinder incorrectly, you could potentially be leaving behind a bomb."
Mr Strong said an incorrectly installed gas heater could result in carbon monoxide poisoning and possibly asphyxiation.
The case saw the tradesman fined about $20,000, but Mr Strong said the fine was often considered just another necessary cost of being able to do the job.
He said asking to see a tradesperson's licence was the best form of protection for customers. "By producing a licence you're just showing that you've jumped a few hurdles to be in the position where you're able to do the job, and do it correctly.
Mistakes can still happen, but if you're dealing with a licensed practitioner you've got a fallback, a degree of protection."
There were 21 prosecutions against unauthorised tradespeople in New Zealand during the 2012 financial year.
Consumers can also check to see if a tradesperson is authorised to carry out work at the board's website, pgdb.co.nz.