Builders and energy groups clash over construction code

The state government is consulting with the sector amid calls for urgent reforms following the financial collapse of one of the nation's largest home builders, Porter Davis.

Leading the charge, the Housing Industry Association is urging the deferral of major changes stipulating how Victorian homes will be constructed under the National Construction Code.

The code lifts minimum energy-efficiency standards for new builds from six- to seven-star ratings and creates design requirements for accessibility.

If they were pushed back at least a year, as has happened in other states, builders and customers would have more time to adjust, the housing association's Keith Ryan said.

"Significant changes will be required to most existing home designs that customers can see when they visit a builder or visit display homes," he told AAP.

"Customers looking at home designs for land they have bought or plan to buy, face great uncertainty the closer we get to October 1."

However, the Energy Efficiency Council argues homes can be built cost-effectively to seven stars, largely through better design and orientation.

While Victorian builders - like others across the country - are under strain, they've been given ample notice and support to adjust, the council's Rob Murray-Leach said.

Builders could make strides towards seven stars if they considered a home's positioning on a block and which way windows faced.

"In a way, seven stars is just asking builders to think properly about design and orientation," Mr Murray-Leach said.

The disability royal commission has identified a lack of accessible housing as a significant issue.

More than 10,000 Australians with severe or profound disability experience homelessness each year.

Victorian builders have ramped up their push for an overhaul of industry rules since Porter Davis slid into liquidation.

Urban Development Institute of Australia national president Maxwell Shifman highlighted the need for Victoria's planning system to be streamlined, blaming delays and extra costs for contributing to the demise of struggling companies.

He is confident conditions will improve following the Porter Davis collapse but said government support would come too late for some.

"If they addressed some of these issues earlier, we might have been able to avoid some of the massive failures that are occurring at the moment," he said.

Mr Shifman pointed to reductions in overall approvals for housing and said rapid reform was needed to improve numbers as Australia's population started to grow again.

The Housing Industry Association is also pushing for an overhaul of the Domestic Building Contracts Act.

Master Builders Victoria interim chief executive Michaela Lihou said the act should be reviewed and include rise and fall clauses.

Fixed-price contracts were not fit for purpose with labour and material costs now impossible to forecast, she said.

There were also restrictions around when builders could get paid according to stages, leading some having to bankroll projects when delays slowed stages down.

Premier Daniel Andrews has concerns about Porter Davis' conduct, particularly over allegations of baiting customers and leaving them without insurance.

The home builder's customers are organising a protest at the Victorian parliament on Sunday to call for government support and deposits to be returned.

Australian Associated Press