by Tristan Stanley-Cary, Architect, TPA DMN TASC member and Educator

What’s In 02 Is progress happening in WA for energy efficiency?

In the WALGA discussion paper “Supporting the Trajectory for Low Energy Buildings 2022” – WALGA sets out several opportunities for both state and local government to support increased energy efficiency of buildings. Of particular interest to thermal performance assessors (TPAs) are recommendations to shift energy efficiency into the planning phase, mandate accreditation of energy assessors, and introduce compliance inspections on site.

Currently, energy compliance is demonstrated at the certificate of design compliance (CDC) / building permit stage. At this stage of a project - windows, wall heights, setbacks and shading are often locked in by a planning approval, and major changes are not generally possible without requiring an amended planning application.

Compliance with energy efficiency requirements often means the NCC and glazing/frame specifications meet code, which typically adds significant cost. Bringing energy compliance forward in the project timeline would enable TPAs to assist with more design changes such as window size and placement, wall heights, shading and potentially even room placement or other further costs – all of which may not add cost, but can increase thermal performance substantially.

This may require a shift in thinking from designers and builders, who may still see energy compliance as a quick tick off before submission for CDC/permits – but with a shift to 7 stars, ensuring the design is right at the outset, will become more critical. This is not a new approach, NSW currently requires energy efficiency requirements are demonstrated at the planning stage for residential projects, and Victoria is considered a similar state-wide planning policy.

Where energy compliance comes into a project is a topic worthy of further discussion – while an early review is good, designs can change quite dramatically as a result of planning and engineering – so a planning stage energy report may not align to what ends up being documented.

Mandating assessor accreditation is also being considered as a measure to help improve energy efficiency in buildings. Currently only NSW and the ACT have mandatory accreditation for assessors, and while assessor accrediting organisations have long pushed for mandatory accreditation - it is difficult to get traction in this area, with the ABCB claiming it is up to the states to implement regulations around accreditation. Calls to the AIBS and state building departments also have not yet yielded any results – perhaps a state planning policy could be the key here, particularly if tied into energy assessments required at the planning stage.

Currently, the as-built performance of many houses does not match what is specified, simulated, or certified at the CDC/permit stage. Currently, WA does not require inspection of single dwellings for occupancy certification – the permit holder simply signs a declaration that all works have been completed in accordance with the permit and requirements. In a 2019 report from DMIRS – audits showed that nearly one in three energy efficiency elements did not comply with NCC requirements. It is one thing to mandate minimum 7-star NatHERS ratings, but if the simulation doesn’t match what is installed on site, is the regulation working?

We will see the outcome in July of the building ministers’ meeting, and know if the draft NCC22 provisions will be adopted by the states. HIA has been lobbying hard to delay a shift to 7-star NatHERS ratings, but regardless of the outcome of the July meeting - governments at all levels now largely support moves to improve energy efficiency. Claire Lings, from WALGA, noted that 80% of local governments in WA have sustainability measures in their planning instruments covering the built environment.

We are seeing this progress in many areas - The Department of Communities in WA mandates minimum seven stars for all their social housing projects, and Victoria is pressing ahead with mandating a minimum 7-star NatHERS rating, regardless of what comes of the updated NCC22.

I recently quoted on TPA consulting for some single dwellings to be designed and built by a local authority in a Pilbara – one of which was to have a 10-star NatHERS rating. DMN have launched the True Zero Carbon Challenge, with many designers and TPAs excited by the prospect of zero carbon housing, and estates such as the Witchcliffe Eco-village (which recently increased the minimum required NatHERS rating from 7 to 8 stars) continue to push energy efficiency as priorities.

Perhaps we will see a shift to higher energy efficient housing in WA regardless of whether the building ministers decide to adopt the proposed 7-star changes - through a state-wide planning policy. Independant local authorities or a state-wide planning instrument may mandate higher performance requirements, coupled with mandatory accreditation of TPAs and on-site inspections of single dwellings, we should see a significant improvement in the thermal performance of WA housing.

Tristan Stanley-Cary, Architect, TPA (WA representative on DMN TASC) and Educator.

References: WALGA Support the Trajectory for Low Energy Buildings Discussion Paper 2022 https://www.afr.com/property/commercial/ home-builders-push-for-easier-energystandards-20220525-p5aod1 What’s In 02