NEW homes built in Victoria from next year are set to require 7-star energy efficiency standards in a move that could slash owners’ power bills by up to 30 per cent.

Research has revealed that despite some extra costs in construction, owners of effici - ent homes can reap an 11 per cent return on their investments.

Building companies and experts say the keys to meeting the new standards – likely to be implemented under a national code in September – would be the position of properties on blocks, insulation quality and modern appliances.

And the Victorian government is now backing 8-star standards for newly built homes within five years, based on advice from Infrastructure Victoria.

The latest 30-year strategy released by Infrastructure Victoria found that achieving a “7-star NatHERS rating through smart design does not add significantly to construction costs”.

“It can reduce energy bills by 30 per cent and each 1.0 star improvement may add around $9000 to the value of the home,” the strategy suggested.

Sustainability Victoria is now running a 7-star home program ahead of construction code changes, providing training for builders and rebates to help with costs.

Chief executive Claire Ferres Miles said efficient properties were “the future of homes”.

“Builders are proving that energy-efficient homes can be designed and constructed using existing materials and technologies at an affordable price,” Ms Ferres Miles said.

As part of the verification process, giant fans are installed at the doorways of properties to test for air leakage that can deflate efficiency and add to a home’s running costs.

G-LUX Builders pre- construction manager Spiros Chasiotis, said using “sustainable materials does not always have to be more expensive”.

Some of the hi-tech methods used by the company include special ventilation systems, Mr Chasiotis said.

“Our homes are wrapped in an airtightness membrane that prevents air leakage,” he said.

VCON Homes operations manager Ahmad Kassab, said differences between a 7-star home and a 6-star home were not complex but made a big difference to residents.

“A great example is our 7.2- star Craigieburn home, it wasn’t much of a change. We focused on optimising orientation, increasing the thickness of insulation, draught sealing around windows and doors and double-glazing windows,” Mr Kassab said.

Infrastructure Victoria acting chief executive Jonathan Spear said there were clear benefits to consumers but also a broader benefit of reducing stress on the electricity grid.