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Tropical and sub-tropical living

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Staying comfortable in the tropics while reducing energy use doesn’t have to involve spending a lot of money.

Our tips focus on the climate-friendly features already in your home before resorting to the air conditioner and ensuring it won’t need to work as hard. With good design and careful management you can stay comfortable while saving on your energy bills

Catch the breeze

Locate the breeze flow around your home by opening windows, shutters and doors and situating seating areas to take advantage.

Floor plan of a home indicating air flow

Cross ventilation only works when outside air is cooler than inside. When it’s hot and still, close doors, windows and curtains to keep the heat out.

Take advantage of high windows and vents. As hot air rises it draws in cool night air or cooler daytime air from shaded areas of the building, enhancing the effect of cooling breezes.

Cleaning your fly screens with a brush or hose will help the flow of cool air, and can be done with the help of a brush or hose. Circulating air through your home also helps stop the build-up of mould.

Fans

Place furniture to take advantage of their effect and set up pedestal fans where ceiling fans don’t reach.

If you have high ceilings, consider lowering fans on droppers to avoid pushing any warm air near the ceiling down into the room.

You can also use fans to increase the effectiveness of your air conditioner. Running both allows the air conditioner to run more efficiently at a higher temperature setting for a shorter time.

Shop around for the most effective and energy-efficient fans—noise levels and performance vary.

Sub-tropical tip: If heating, switch your fan to reverse rotation to better distribute warm air through the room.

Get in the zone

The bigger the space you need to cool, the greater the energy use. If you need to turn on the air conditioner, only cool the room you’re using and close doors to other rooms.

Set your thermostat from 25°C to 27°C and consider running ceiling fans. Some air conditioners have a dehumidifying function. This will use less energy while still delivering a comfortable indoor environment in humid climates especially when used with a fan.

See the Design for climate and keep cool guide for tips on using your air conditioner.

Low-temperature lifestyle

If possible, plan activities and physical pursuits around cooler times of the day. Plan trips to the supermarket or other air conditioned spaces to escape hotter parts of the day.

Night purging

Open up your home in the evenings to allow cooler air from outside to push out warm air that’s built-up during the day.

Diagram showing night purging air flow

Convection causes warm air to rise, drawing in cool air

Many homes in tropical Australia feature sleep-outs on the verandah to take advantage of the night air. Monitor morning temperatures and close up the house before the day heats up.

Ventilation in the roof space lets hot air out to be replaced by cooler air. This helps stop heat transferring through the ceiling to the rooms below and is particularly important in uninsulated homes.

Drying clothes

Drying clothes in front of a fan during the wet season will reduce your energy bill as well as avoid the build-up of moisture that can lead to mould.

If you need to use a clothes dryer, spin dry on maximum speed first to reduce drying time and clean the lint filter after each load. Running the dryer on medium heat takes longer than when on high, but will use less energy and can be less damaging to your clothes.

When buying a new dryer, look for the most efficient model you can afford and take running costs into account. Look for the Energy Rating label to compare the product’s energy efficiency with other models.

Heat pump condenser dryers are generally more energy efficient than standard condensing dryers, and may be cost-effective if used regularly. Condenser dryers work by removing moisture from the air before releasing it, reducing condensation. Condenser dryers also don’t require anywhere near as much ventilation as vented dryers do. This allows for more options as to where to place your dryer in or around the home.

Monitor the weather

To help read your local weather more accurately, consider investing in a home weather station with an indoor display or alert system. These range from inexpensive temperature gauges to digital technology that can measure solar radiation, expected rainfall, wind speed and direction, humidity and more.

A convenient read-out from inside the home can help to respond to outside conditions. For example, operating blinds and awnings effectively and capture passing breezes as they occur.

Switch to energy-efficient lighting

While they might cost more upfront, LEDs are much more efficient than other forms of lighting and will save you money over the long term.

LEDs consume 80% less energy and last 5 to 10 times longer than halogen lights. They will also reduce the amount of heat in your home, particularly if you’re replacing halogen downlights. It takes up to 6 downlights to light the same area as one pendant light, so switching to LEDs and pendant lighting can have a real impact.

As downlights require a minimum clearance around ceiling insulation they can reduce the effectiveness of insulation. This is another reason pendant, ceiling-mounted or track lighting is a better option. Ask a lighting specialist to provide approved covers with your LED downlights to reduce the impact on the insulation. Sealed downlights are another option.

See our energy-efficient lighting tips and links to the Light Bulb Buyers Guide, Light Bulb Saver app and video.

Cool pool technology

Pool pumps can account for around 18% of household electricity use. By making smart purchasing decisions and using your pump efficiently you can reduce your running costs.

Select a minimum 5 star energy-efficient pool pump at the smallest pump size for your pool—variable speed pumps often have higher efficiency. See the Voluntary Energy Rating Labelling Program (VERLP) for energy-efficiency ratings of various pool and spa pumps.

To get an idea of the true costs of your pump, ask your retailer to do a cost comparison between the running costs of an energy-efficient versus a less efficient pump over 3 to 5 years.

Once it’s installed, use a timer to manage run-time and keep the skimmer basket and pool filter clean to reduce the load on your pump.

Installing and using a well-fitted pool cover significantly reduces evaporation, pump running times, water bills, and the need for chemicals and cleaning.

Plant shade trees and vines

Shading is vital in hot conditions to reduce the heat entering your home from walls and windows. Planting trees for shade on the eastern and western sides of a single-storey, older-style 3 star energy-rated home can result in significant energy savings.

Shading is particularly important if your home is made of heavier construction such as concrete or brick, which takes longer to cool down. Overhead shading can block the higher angled sun in summer for north and south facing openings.

Adjustable shading from pergolas blocks low-angle morning and afternoon sun for east and west orientation of your home. If you intend to install a solar PV or solar hot water system you’ll need to plan so trees give the sun access to the appropriate area of your roof.

When planting out pergolas, use evergreens to block sunlight. Use drought-tolerant ground-cover plants rather than paving to help reduce ground temperature in summer. 

If renting, you may get permission or assistance from your landlord for plantings, as it will improve the livability and value of the home.

Fruit trees such as mango may take longer to grow than other varieties, but provide abundant shade.

Make sure plantings allow sun access to the north so it can warm your home in cooler months (where applicable). Floors made of heavier construction will store heat during the day and release it at night to warm your home.

For more information on shading and planting trees see the Your Home website.

Longer-term investments

Go solar PV

A solar PV system offers the potential to reduce your household electricity bills. It’s also a major step in the transition away from fossil fuels.

The Australian Government’s new Solar Consumer Guide provides free and expert guidance on rooftop solar and batteries for your home or small business.

This step-by-step guide provides information to help you choose, use and maintain a rooftop solar system that suits your needs and maximises your savings. It includes information on how to find a solar retailer or installer and what questions to ask when seeking quotes.  

The guide was developed with support from government and industry experts, including the Australian PV Institute and the School of Photovoltaic and Renewable Energy Engineering at the University of New South Wales.

Check out the Solar Consumer Guide.

Switch to an energy-efficient hot water system

Hot water can account for 25% of your energy use. If replacing your hot water system, research the right type and size of product for your needs. Choose the most suitable energy-efficient model you can afford and avoid paying for capacity you don’t need. See our rebates page for available assistance.

For tropical climates, heat pump and solar hot water are often suitable. You may be eligible for financial assistance to help with the cost of installing a system under Small-scale Renewable Energy Scheme (SRES).

Ensure you understand the information on safety and maintenance for your new system. This is particularly important for storage hot water system that you’re switching back on after a period of non-use.

The water needs to be heated to above 60°C for at least 35 minutes before use, killing any bacteria that may have grown. It may take several hours for the water to reach this temperature.

For more information see the Hot water system page.

Insulate your ceiling and roof

Insulation helps to keep the sun’s heat out of your home during extreme temperatures, saving on your energy bills.

Insulation can be sensibly and safely added to many existing homes. Research the type and level of insulation most suitable for your home and climate.

For air conditioned homes, the use of bulk and reflective insulation in the ceiling and roof is recommended. In the ceiling, select R3.5 or higher bulk insulation. Consider multiple layers of reflective foil to create a one-way heat valve effect. For walls, use of bulk and/or reflective insulation is recommended.

Condensation prevention needs to be considered in regard to roof and wall insulation.

For more information on insulation see the Your Home website.

Sheet metal or tiled roofs

Under a sheet metal or tiled roof, a reflective insulation system should be used. A tiled roof should have sarking—a double-sided reflective-foil product—under the tiles as well as ceiling insulation.

Including a foil-blanket system under sheet metal roofing will quieten the sound of heavy rainfall. Ventilate roof spaces with fans or whirlybirds and design for condensation removal.

Verandah roofs

Verandah roofs should be insulated with reflective-foil insulation to reduce radiant heat gain, as this impacts on your indoor temperature as well as making outdoor seating areas uncomfortable. Consider installing energy-efficient ceiling fans.

Sub-tropical tip: Roof insulation will also help to keep warmth inside your home during the cooler months. Using bulk insulation in external walls is also beneficial.

Light-coloured roofs

Your first line of defence in cooling your home is to stop it from absorbing and storing the sun’s heat. Light-coloured roofs (also known as ‘cool roofs’) can reflect up to 70% of summer heat.

The easiest time to apply light-coloured roofing is when building. However, if you need to replace your roof, steel roofing solutions with reflective paint technology are highly effective.

Cool steel roofing material with reflective paint technology

You may also consider installing a fly roof. A fly roof shades your entire home, protecting it from radiant heat while allowing cooling breezes to flow underneath.

Fly roof

A fly roof can shade your whole home

Sub-tropical tip: A white roof or shading will affect your home’s indoor temperatures during the cooler months. Allowing solar access to north-facing living areas and sealing gaps and draughts will help you retain warmth when you need it. Protect from direct sunlight with adjustable shading to avoid heat gain in the hotter weather.

Improve your windows

A major requirement in the design of tropical homes is the size and orientation of windows, openable panels and doors.

If renovating, improving window design to increase airflow can make a real difference to comfort, reducing up to 90% of heat gain.

Windows with maximum opening areas such as louvres or sliding windows can be tightly sealed when closed. Check the seals on windows and improve them if necessary. Avoid fixed glass panels. Be sure to install fly screens to protect against tropical insects, bats and reptiles.

Diagram of windows, sliding windows, louvres, casement window

Louvres and casement windows are best for breeze capture.

A small number of windows on each side of your home will encourage air flow

Larger windows or openings should be located on the downwind side of the house and smaller openings on the breeze side. All openings should be well shaded.

Check with an energy rater or window specialist whether toned or low e-glass could improve your comfort levels. Consider tinting windows that are exposed to the sun.

Mould

Mould is a fungal growth that can occur in your home in areas that are damp, dark and poorly ventilated. It grows on a variety of surfaces, including timber and fabrics, wet areas, bathrooms, and kitchens. Rough, porous surfaces are often worst affected.

Apart from damage to your home and furnishings, mould can have an unpleasant odour and cause irritation or serious health risks. Prevent the build-up of moisture as much as possible.

Reducing mould

  • Keep your home properly ventilated.
  • Dust, clean and dry surfaces regularly, including walls, window glass and frames, particularly in the wet season.
  • During high humidity, keep air circulating with a fan or air conditioner (look for models with a dehumidifying feature).
  • Install exhaust fans in bathrooms and kitchens.
  • Where possible, ensure stoves, washing machines and dishwashers are fitted with an exhaust system.
  • If you’re renting, consider buying a portable dehumidifier and run it overnight to reduce energy demand during peak times.
  • Pay attention to dampness on walls, timber, carpet, furniture and fabrics and dry out or clean regularly.
  • Install clothes dryers in the carport or verandah where possible and keep them protected from the weather—dryers installed inside should be vented to the outside where practical.
  • Condenser dryers that extract the vapour from the air are a better choice for reducing condensation.
  • Keep bathroom doors closed when showering and run the fan during and after your shower to avoid a build-up of steam. 
  • Consider installing insulation in walls to reduce condensation and improve your home’s energy efficiency.
  • When painting, ensure that mould has been removed from surfaces.
  • Select gloss or semi-gloss paints, as these repel mould more effectively than matt finishes. Look for paints, grout and timber stains with mould-inhibiting additives.
  • To get rid of existing mould, a solution of 80% vinegar and 20% water on a microfibre cloth is an ideal solution (rinse the cloth at regular intervals to avoid spreading mould).
  • Note that while bleach can help reduce the appearance of mould, it’s ineffective at killing the spores.

Managing mould with your air conditioner

Operating an air conditioner in a sealed room dries the air, which can be effective in managing mould.

Switching off the air conditioner and opening windows lets humid air inside, which may cause condensation to form. Keep the room closed before opening it up to access breezes or cooler night air.

corner of window showing condensation and mould

Condensation can lead to problems with mould

Condensation in apartments caused by differences between outdoor and indoor temperatures can cause problems. For example, where a neighbour sets their air conditioner to a lower temperature overnight, cooling the slab floor or ceiling.

If the air temperature is warmer inside your home this can cause condensation to form on the tiles, ceiling or metal studs in a plaster wall. You may need to speak to others in your building on how to best manage the situation.