Better building norms are good for climate, your health & wallet

The recent IPCC report highlighted we must urgently transition to a low carbon future. One low hanging fruit is to improve the sustainability of new and existing housing. Minimum performance and quality requirements for new housing in Australia are set via the National Construction Code. The last significant change was in 2010 with the introduction of the six-star requirements. These requirements are at least 40% less stringent than international best practice.

A suite of proposed changes to energy efficiency section of the National Construction Code are a good step forward. However, a lot more can be done. And improving building quality requirements isn't just good for the climate — it also delivers enormous health benefits, slashes energy bills and makes our homes more comfortable.

Change is underway Proposed energy efficiency changes for the National Construction Code 2022 include: • an increase in the minimum thermal performance of homes from six stars to seven stars • whole-of-home requirements for performance of heating, cooling, hot water, lighting and pool heating equipment • new provisions designed to allow easy addition of on-site solar photovoltaic panels and electric vehicle charging equipment • additional ventilation and wall vapour permeability requirements. The Regulatory Impact Statement — a document aimed at helping government officials understand the cost-benefit impacts of a proposed regulatory change — has also been released.

Overall, it finds the costs for proposed more stringent requirements will outweigh the benefits for society. In better news, it finds that for the majority of households, any increase in mortgage repayments from the additional costs of higher standards will be offset by a reduction in energy costs. In other words, you save so much on energy costs over time that it doesn't matter you have to borrow more to pay for these building features. The seven-star standard will reduce heating and cooling energy for new housing by about 24%, slashing energy bills. The changes future-proof housing by reducing costs to add renewables or electric car charging once the house is built. And with issues of mould and condensation in Australian housing, changes will make our housing healthier.

Historically, higher standards have been met by boosting specifications like insulation and double glazing. These new standards will shift attention to cost-effective strategies like orientation and site-responsive design, as it becomes harder to achieve higher stars through specifications alone.

We need to acknowledge the influence of house size and materials usage on total energy consumption and factor in the carbon footprint of building materials. We will need more focus on summer performance. This will require solutions like adjustable shading. There is no point improving regulations on paper if we can't deliver it in practice. While the focus of these changes is on new housing, we must not forget the millions of existing homes which need to undergo deep retrofits to improve sustainability and performance. (The Conversation)