With kitchens, bathrooms and outdoor areas the most popular spaces for a makeover, home owners can cause serious injury to themselves or others when taking on projects such as building a deck, plumbing or electrical work they are not skilled to do. Renovation and real estate experts say the popularity of DIY has increased following the onslaught of home renovation TV shows.  

Business information analysts, Ibisworld, has forecast that within five years Australians would be spending more than $60 billion a year on home renovation and maintenance. However, REIV CEO Enzo Raimondo tipped this figure was already closer to $55 billion a year.

“The analysts said the hardware store sector would grow most, with projected growth of 16 per cent,” Mr Raimondo said. He said home owners could be at risk of over capitalising on a property - even if the job is done well - and the opposite if the project is poorly executed. A recent British survey, Mr Raimondo said, reported poor DIY could knock up to 11 per cent off the selling price of a home, with nine out of 10 home buyers saying they would lower their offer if they noticed botched home improvements.

“Translating those figures to Victoria, that would mean up to $35,000 off the regional  Victorian median house price of $324,000 and about $70,000 off the Melbourne median house price of $649,000,” he said. “A key lesson is that work should be done well if it is to add value to a home. That means being sure you have the skills and experience for the tasks and, if not, getting professional tradespeople to do the work. Also, it is not cost-effective and is potentially dangerous to attempt work such as wiring and major plumbing jobs. “

Reece Bathrooms spokesperson Adam Watson said DIY home owners “have a lot to lose and little to gain” in not using trained building and renovation professionals.

Mr Watson said the National Injury Surveillance Unit at Flinders University in South Australia reported more than 25,000 people were hospitalised from DIY-related injuries in 2011. The research centre's mission is to contribute to reducing the burden of human injury and adding to knowledge of its nature, causes, effects and control. It works in collaboration with the Australian Institute of Health and Welfare.

“DIY plumbing is extremely dangerous, and depending on the application, could cause anything from a small injury to, in the worst case, death,” he said.

Mr Watson said Reece aimed at educating people on the implications of going it alone in plumbing jobs. Each year its annual DIY Disasters competition attracted dozens of entries that showed dodgy plumbing in homes. It was the unexpected discovery of a homemade heating device rigged to heat bath water that resulted in South Australian plumber Matthew Longmans highlighting Australia’s worst DIY Disaster.

Mr Longmans said a 98-year-old man had risked electrocution in using the homemade heating device. “The man had performed this ritual every night, without the use of safety switches,” he said. “If the element had slipped off, the electricity would have gone straight into the water. He is lucky to have come out unscathed.”

Shayne La Combre from the Plumbing Industry Climate Action Centre said each year Australians risked injury or death in performing illegal building jobs.

“In countries around the world where plumbing systems are not up to standard - and they are in this country - it literally is a matter of life and death. And we’re one bad plumbing mistake away from that sort of risk here.”

Mr Longmans said he saw varying levels of disastrous DIY jobs at least once a month. “We see crazy things all the time, but people don’t realise the risks involved in DIY. They try to save a dollar, but the safety implications are not worth the money saved,” he said.