A relaxation in energy efficiency requirements will make it harder for architects and engineers in Australia to design sustainable buildings, a group of 17 sustainable built environment professionals has warned.

The group, which completed modelling on proposed changes relating to the Australian Building Codes Board in early June which relax standards with regard to energy efficiency in construction, says the proposed changes would allow clients to set a reduced bar in terms of sustainability and create a situation whereby architecture and engineering firms would find clients specifying lesser requirements for the energy performance of their buildings.

Group spokesman Darren O’Dea said the modelling had shown that the new rules are ‘far more lenient’ compared with existing requirements.

“We’ve modelled it against the existing provisions and it means you will be able to pass much easier with much less effort,” O’Dea said.

“The outcome of the process will be poor performing buildings across Australia. We as an industry are concerned that we will be in a position where we will be more challenged to produce sustainable buildings because clients will set the bar lower and build something cheaper.”

Included in the revisions to the National Construction Code 2016, the proposed changes aim to make it easier for project proponents to innovate across all building types, and aim to promote a performance based approach to energy compliance and make this equally valid to the more prescriptive ‘deemed to satisfy’ approach.

Under one of the changes, for example, a Class 2 multi-residential building will be included under a similar type of energy and thermal assessment regime as a Class 5 commercial building.

This will mean that whereas currently, each individual apartment needs to achieve a five star NatHERS rating as well as the whole building achieving six stars, going forward, the whole building will still need to achieve six stars but none of the apartments will need individual assessment – a situation some experts suggest may result in situations whereby some apartments were way below standard in terms of thermal comfort and energy performance but the average could still be achieved because some others were outstanding.

Under another change, whilst in the 2015 Building Code of Australia, section J contains a stated objective of reducing greenhouse emissions and a list of functional statements for achieving that objective (including ensuring that a building is capable of efficiently using energy and that a building’s source of energy for heating is sustainable or efficient), neither the objective nor the functional statements are contained in the 2016 code.

O’Dea’s comments follow calls from building sustainability expert Alan Pears to defer implementation of changes to building energy regulations under the 2016 code until further consultation could take place.

According to a recent report in The Fifth Estate, Pears says the ACBC has failed to effectively engage with stakeholder and develop ‘appropriate energy performance measures that are in the interests of society’.