Adapting to climate change

In Australia, the average life of a brick home is 88 years and a timber home is 58 years (Snow and Prasad 2011). Many homes last much longer than this. Decisions that are made about homes today will continue to have consequences for many decades.

Many people already consider their future situation when buying or building a home: for example, whether it can accommodate a growing family, or what its likely increase in value will be. However, less people consider what the future climate will be like and whether the home will suit these conditions. If potential changes to the climate are considered when a home is being designed or altered, it is likely to remain comfortable for longer.

Photo: Sebastian Mrugalski

Our changing climate

It is difficult to say precisely what impacts our changing climate will bring to different areas across Australia. But research suggests it is likely our average temperatures and sea levels will continue to rise, we will experience more days of extreme heat in summer and there will be longer periods of drought over southern Australia (CSIRO and BOM 2020).

Scientists also anticipate there will be more days of extreme fire danger and a longer fire season in southern and eastern Australia. And while reduced rainfall is predicted in winter and spring in southern mainland Australia, it is likely there will be more high-intensity storms with heavy rainfall and strong, damaging winds (CSIRO and BOM 2020).

You can learn more about the potential impacts for your local area and consider these when you are designing, renovating and building. This information can help you build a resilient, comfortable and adaptable home for the future.

Key Australian sources of information are the Climate change in Australia website and the State of the Climate 2020 report. For state and territory government websites see References and additional reading for more information.

Good design for a changing climate is design that is flexible enough to adapt to prevailing conditions while optimising the occupants’ comfort.

Considerations

The National Construction Code (NCC) sets out performance standards for houses built in areas that are prone to bushfires, cyclones and flooding. Adaptive strategies that go beyond these minimum standards should also be considered.

When designing or redesigning a home, consider the following questions:

• What are the local climate variables that could affect the building?
• Will predicted climate change impacts affect the site and the building?
• What are the likely consequences to the home in the event of extreme weather?

Building flexibility into the design of a house and considering where your home is situated on your block will help you manage changing climate conditions. Options might include:

• ensuring that there is enough space on your site for extra rain or stormwater storage
• building more substantial footings under a deck so that it can easily take the weight of a roof if more shade is needed around the house
• creating a cool retreat in your home, ideally located on the cooler, southern side or in the central part of your home, with additional shading and insulation.

Source: Palmer et al., 2013

Strategies set in place early to adapt a house to a changing climate may reduce future costs. Seek professional advice (for example, from an architect) to identify adaptation options and compare them against other factors:

• How effective will the option be over the life of the house? Is it flexible enough to respond to the projected local changing climate conditions?
• How practical is the option, and is it easy and relatively inexpensive to maintain?
• Are there other benefits, or undesired side effects, that could arise from the option?

The best adaptation actions are those that offer other benefits. For example, concrete floors recover well should the house be flooded, and also have high thermal mass which can be used to reduce heating and cooling costs.

However, adaptation actions for one climate change impact could cause a home to be less well adapted for other impacts or could also create a home that is less liveable. These effects can be avoided or negated through smart design or material choices. The table below gives examples of smart design choices for adaptation.

Examples of unintended results of adaptation actions and possible solutions

Insurance

Adequate insurance will help to protect you financially against extreme events. To ensure that it meets your needs, you should:

• know the specific climate change impacts relevant to your region
• review your current insurance
• consider seeking professional advice.

You can design or renovate your home to take into account the sort of climate impacts you expect to be most relevant for your area.

Temperature increase and heatwaves

One of the main expected effects of global climate change across Australia is increasing temperatures and a greater number of extremely hot days (CSIRO and BOM 2020). Australian households need to consider how they can adapt to maintain comfort, manage household energy costs, and reduce the risk of heat stress and heat-related illness and mortality.

The need to keep your home cool during the summer months will be greater. On the other hand, there should be less need to heat the home in winter. Good passive design can lessen the need to rely on air-conditioners and help to capture the savings from lowered heating energy needs.

Consider the impact of increased numbers of heatwaves in your region. Over the past several decades, heatwaves have increased in duration, frequency and intensity in many parts of Australia (Steffen et al. 2019). New homes are not typically constructed to provide maximum protection from heatwaves as standard. In urban areas, tree canopy cover is decreasing as development intensifies. Urban areas may be particularly prone to heatwave conditions because of the ‘heat island’ effect, in which the abundance of heat-absorbing materials such as concrete, and lack of vegetation, increases their temperature compared with the surrounding area. Good tree canopy and other vegetation around your home and neighbourhood can reduce the impact of the urban heat island effect (see Green roofs and walls).

In addition, electricity demand rises sharply during heatwaves because of increased air-conditioning usage, contributing to blackouts. Excess peak demand drives up electricity prices, making air-conditioning use during heatwaves too expensive for some low-income households.

The NCC heating and cooling load limits under the NatHERS compliance pathway assist to keep homes at a comfortable temperature year-round. The load limits have been developed using the 2022 NatHERS climate files based on historical weather data, and the requirements change depending on which climate zone the home is built in.   

Projected number of days over 35°C

Source: Webb and Hennessy 2015

Photo: © Veronica Sagredo, Blue Click Photography

Overall, adapting to cope with increased temperatures requires appropriate heat-resistant building materials and design. Key design strategies include:

• orientating living rooms appropriately and using shading to minimise summer heat gain
• using thermal mass appropriately
• locating bedrooms in the coolest part of the building and using insulation, shading and so on to ensure comfortable temperatures for sleeping
• providing opportunities for night-time ventilation, including natural ventilation and mechanical systems
• using light-coloured roofs and ‘cool roof’ technology (specially designed roofing materials and coatings with high solar reflectance and thermal emittance)
• creating a ‘cool retreat’ – a portion of the dwelling designed to provide comfort during heatwave periods. This could be a shaded, ventilated room or basement that is well insulated and able to be closed off from warmer parts of the house so it can be efficiently air-conditioned
• using cooling technologies powered by renewable energy
• using landscape to decrease the need for cooling (for example, by shading, channelling cool breezes, lowering surface temperatures).

Refer to Passive cooling for more information on cooling design strategies.

Bushfires

The number of very high, extreme, or catastrophic fire danger days is expected to significantly increase with climate change (CSIRO and BOM 2020).

There are several ways you can minimise the risk to your home from bushfires and maximise the safety of occupants, including:

• Install shutters consistent with Bushfire Attack Level (BAL) requirements and suitable sprinkler systems in high-risk zones.
• Ensure that the roof line and gutters minimise the risk of catching burning embers.
• Use building materials that are fire resistant.

There are specific building codes and standards that apply in bushfire prone areas – check whether your home is in a bushfire prone area and any mandatory requirements with your local planning authority. Minimising fuel loads — vegetation and things that burn — close to the home will also reduce the risk. Keep yard growth trimmed, clear dead wood and rubbish often and consider using metal rather than wood for fences.

Refer to Bushfire protection for more information on designing a home in bushfire-prone areas.

Severe thunderstorms and high intensity rainfall events

Climate change is expected to increase high intensity rainfall events caused by weather systems such as thunderstorms and cyclones, particularly in the north of Australia (CSIRO and BOM 2020). It is difficult to predict if thunderstorms — hail, wind and tornados — will also increase in number or intensity. Indications are that hailstorms will increase over the south-east coast of Australia.

Given the significant damage that hailstones can inflict, it may be worthwhile preparing homes for the impacts of hailstorms. Options for reducing hail damage include:

• selecting roof materials that are impact resistant
• designing or installing appropriate window protection.

Photo: Rollashield

Options include:

• designing or installing window protection
• ensuring roofs are well maintained
• creating greater capacity to detain and harvest water from a deluge
• selecting materials that can withstand moisture
• ensuring there are drainage cavities in walls
• improving the detailing to roof edges, open decks, walls and joinery, retaining walls, floors, balconies, wall−roof junctions, and roofs
• ensuring internal and box guttering can withstand a 1-in-100-year rainfall event. Seek design advice from a qualified professional.

Think about options to capture additional rain and use it for the household or garden. Refer to Rainwater for more information.

Cyclones and extreme wind

Although the total number of cyclones is expected to decrease with climate change, high wind events and tropical cyclones of greater intensity may increase and their range could move further south (CSIRO and BOM 2020).

Extremely strong winds can place a great strain on buildings. Damage to homes can cause subsequent damage to their contents. Because of this great strain, a building’s resilience to cyclones and extreme wind should be considered when designing the home. Seek advice from a qualified building or design professional who can assist you to minimise the risks by:

• using improved fixing systems in the roof structure and the subfloor
• designing buildings to minimise the wind loads
• using impact-resistant materials for external cladding
• ensuring building materials are largely waterproof and drainage design is effective, particularly for flashing, vents and penetrations.

In an established home, a home’s resilience to cyclones can be improved by ensuring the structural fixing elements have not been compromised by corrosion, high-wind events or previous cyclones.

Floods

The projected increase in rainfall intensity is likely to result in more flash flooding events (CSIRO and BOM 2020). Flooding can be localised or associated with a river system. Possible impacts include water damage to the home and its contents, the undermining of foundations and the contamination of the home by sewage or mud.

The risk of flooding to a home can be reduced by not building in areas that could flood (for example, along river floodplains and on low-lying coastal areas). Consult a qualified engineer for advice to reduce flooding risk including:

• raising floor level heights
• constructing multistorey homes and using the lower level for non-living areas
• using water-resistant materials (for example, concrete, fibre cement)
• ensuring that drainage allows water to escape after the flood
• raising vulnerable equipment (for example, service meters)
• building a limited-life dwelling to minimise financial outlay (that is, a low-cost home that can be moved or replaced as required)
• building a levee around the house
• designing a garden that will safely redirect water.

Raising floor level heights may not only reduce the risk of flooding in your home but could also benefit passive thermal design in some climate zones (for example, by increasing subfloor circulation to cool the house). However, using fill to increase the height of the floor may disturb acid sulfate soils, so make sure you have a sound knowledge of the site. Refer to Choosing and using a site for more information.

Source: Cox Rayner Architects

Low rainfall

In areas where rainfall is projected to decline, flows into water supply catchments will decrease and droughts will be more severe. Minimising water use, and maximising water efficiency and capture, are essential for ensuring there is enough water for people and the environment.

Key design strategies include:

• capturing rainwater for use onsite (for example, a water tank or bladder)
• recycling greywater for use on gardens or in toilets
• using water-efficient appliances (for example, dishwasher, washing machine)
• using water-efficient showerheads, taps, and toilets.

Refer to Water for more information on reducing water use and maximising water efficiency.

Sea level rise and storm surge

During the 20th century, sea level rose at a global averaged rate of about 1.7mm per year. Since 1993, sea level has been rising at an average rate of 3.2 mm per year (CSIRO and BOM 2020).

Sea level rise can bring water closer to homes. It also increases the likelihood of flood and damage from storm surges when intense onshore winds push waves harder against the coast. With 85% of the Australian population living in coastal regions, susceptibility to both sea level rise and storm surge is concerning.

Greater foreshore erosion could also expose more homes to the impacts of storm surges and sea level rise (particularly for sandy coasts). Stormwater systems may be less able to drain into the sea and therefore may cause flooding further inland.

Coastal communities have 3 potential strategies for dealing with sea level rise and storm surge: protect (for example, construct sea walls), accommodate (live with the impact) or retreat. For the home owner, options for dealing with sea level rise include:

• elevating the home
• ensuring the parts of the home that may flood can cope (for example, the foundations)
• building a limited-life home to minimise financial outlay
• building a transportable home.

For further information about the vulnerability of the coastline of Australia, see Climate change risks to Australia’s coast: a first pass national assessment or consult local government risk assessments.

Source: CSIRO and BOM 2007

State and territory climate change websites

- Australian Capital Territory 
- New South Wales 
- Northern Territory
- Queensland
- South Australia
- Tasmania 
- Victoria 
- Western Australia.

• Australian Academy of Science, The science of climate change.
• Australian Institute of Architects Practice Notes, Environment
• Bureau of Meteorology (2020). Annual climate statement 2020, Australian Government, Canberra.
• CSIRO and BOM (Bureau of Meteorology) (2015). Climate change in Australia: projections for Australia's NRM regions - technical report. 
• CSIRO and BOM (Bureau of Meteorology) (2020). State of the climate 2020.
• Department of Climate Change (2009). Climate change risks to Australia’s coasts: a first pass national assessment, Canberra.  
• Garnaut R (2008). Garnaut climate change review, Cambridge University Press, United Kingdom. 
• Hatvani-Kovacs G, Belusko M, Pockett J and Boland J (2018). Heat stress-resistant building design in the Australian context. Energy and Buildings: 158:290-299.
• Hatvani-Kovacs G, Bush J, Sharifi E and Boland J (2018). Policy recommendations to increase urban heat stress resilience. Urban Climate 25:51–63.
• National Climate Change Adaptation Research Facility, Coast adapt.
• National Climate Change Adaptation Research Facility, Practical guidance.
• Palmer J, Pullen S, Zuo J and Ma T (2013). Adaptation of Australian houses and households to future heat waves. 7th Australasian Housing Researchers' Conference, Fremantle, 2013. 
• Palmer J, Pullen S, Zuo J and Bennetts H (2013). The effect of dwelling occupants on energy consumption: the case of heat waves in Australia, Architectural Engineering and Design Management 10(1–2):40–59.
• Saman W, Boland J, Pullen S, de Dear R, Soebarto V, Miller W, Pocock B, Belusko M, Bruno F, Whaley D, Pockett J, Bennetts H, Ridley B, Palmer J, Zuo J, Ma T, Chileshe N, Skinner N, Chapman J, Vujinovic N, Walsh M, Candido C and Deuble M (2013). A framework for adaptation of Australian households to heat waves. National Climate Change Adaptation Research Facility, Brisbane.
• Snow M and Prasad D (2011). Climate change adaptation for building designers: an introduction, Environment Design Guide, 1-11.
• Stanley F, Hughes L and Hannah E (2016). Statement from the Australian Summit on Extreme Heat and Health, Climate Council of Australia, Canberra.
• Steffen W, Dean A and Rice M (2019). Weather gone wild: climate change-fuelled extreme weather in 2018. Climate Council of Australia, Sydney: 35.
• Walford G (2001). Rain screen technology. NZ Timber Design Journal 10(3):11–12.  
• Webb, L and Hennessy, K (2015). Projections for selected Australian cities [PDF], CSIRO and Bureau of Meteorology, Australia.
• Zander K, Botzen WJW, Oppermann E, Kjellstrom T and Garnett ST (2015). Heat stress causes substantial productivity labour loss in Australia. Nature Climate Change 5:647–651.

Learn more

• Explore Design for climate to find out how to make sure your home suits the climate in your region
• Review Passive heating and Passive cooling to find ways to keep your home warm in winter and cool in summer
• Visit Bushfire protection for more information on building in bushfire-prone areas

Authors

Original author: Australian Government Department of Climate Change and Energy Efficiency 2013

Updated: Fiona Berry and Caitlin McGee 2020, Department of Climate Change, Energy, the Environment and Water 2023.