Keeping cool

As summer heatwaves intensify across Australia, builders are increasingly seeking ways to design and build homes that offer refuge from the scorching temperatures and remain cool and comfortable through summer – but also offer warmth in winter. It’s also critical that this is done without placing an undue load on the home’s ongoing energy consumption and running costs. 
HIA’s GreenSmart program outlines a range of integrated strategies that builders can use to improve the thermal performance and energy efficiency of residential builds (see website on page 25). These include:

• shading and eave overhangs to minimise solar heat gain 
• placing windows to catch cooling cross-breezes 
• appropriate use of thermal mass and insulation
• using light-coloured roofs and walls to reflect solar radiation 
• inclusion of energy efficient air-conditioning systems where required.

Earth-friendly insulation 

Insulation acts as a barrier to heat flow, which helps in keeping internal temperatures more stable. A well-insulated home will be naturally cooler in summer and warmer in winter. Currently, the BCA specifies minimum R-value requirements for insulation based on climate zones, but these are likely to change under the NCC 2022 proposed reforms which includes increases to energy-efficiency provisions in new homes. 

The effectiveness of insulation was proven by a council initiative in Birdsville, Queensland, where summer temperatures regularly hit 40oC. The council, in collaboration with Knauf Insulation, installed Earthwool® wall, ceiling and underfloor insulation into every viable home and public building in the town, to help residents stay more comfortable over the harsh summer months. 

‘Over the following year, the average participating home in Birdsville saved more than 20 per cent on energy bills and was less reliant on cooling appliances,’ says Knauf Insulation’s technical product manager, Guy Manthel.

Earthwool® insulation comes in a range of R-values to suit different energy requirements. Ceiling and wall batts are available in pre-cut rectangles, sized to suit most applications, or builders can select a multi-use roll and cut batts to custom sizes.

Manufactured from up to 80 per cent recycled glass with a sustainable binder called ECOSE® Technology, Earthwool® offers excellent thermal and acoustic performance, is non-combustible, won’t absorb moisture, and contains no added formaldehyde or petro-based chemicals. This makes it a smart and durable energy-efficiency solution for Australian homes. Guy says it’s also a popular choice with home builders and trade professionals because it’s soft, easy to handle, less dusty and less itchy. 

For fast and accurate specification, Knauf has created an online insulation pack calculator  (see website on page 25) to help builders quickly and easily calculate the correct quantity of Earthwool® required to meet the area size and R-value for each project. 

Keeping it cool

Air-conditioning is often a non-negotiable inclusion for new home buyer and renovators. Speedy, effective and quiet, reverse cycle air-conditioners are also the most energy-efficient heater and cooler of all types, irrespective of fuel source, according to YourHome (see website on page 25). 

As a global leader in air-conditioning, Daikin has been delivering innovative and effective climate control in Australia for over 50 years. The company engineers smart technologies to deliver systems that cost less to run – from both a dollar and carbon perspective – backed with intelligent drivers that give homeowners unprecedented control over temperature, zoning and running times, for maximum cooling performance on a minimal energy expenditure.  

Daikin’s systems are tailored for the Australian climate. With summers getting hotter, Daikin has re-engineered its outdoor and indoor units to ensure they can withstand extreme temperatures. ‘Our Australian-made R32 Premium Ducted unit, for example, features a newly designed outdoor unit that allows it to operate in ambient conditions up to 50°C,’ says Raj Singh, national product manager, Daikin Australia. ‘Additionally, the indoor unit features upgraded control systems, and can reliably operate in roof temperatures up to 85°C.’ 

With the typical home divided into separate areas or ‘zones’, it makes sense to only air-condition zones that are occupied. ‘Daikin’s new AirHub Touch Zone Controller for ducted systems gives users the flexibility to deliver precise temperature control when and where it’s needed,’ Raj says.

AirHub is available in two versions:

• On/off zone control allows users to control up to eight individual zones. Featuring Airside Control, the indoor unit fan speed is automatically reduced when zones are off, for quieter operation and greater energy savings.

• Linear zone control enables users to switch up to eight zones on and off as well as setting the zone temperature to within ±2°C. OptiZone Control regulates individual zone dampers to tailor airflow to the temperature settings and heat load of each zone. 

Homeowners can also control the AirHub remotely from their smartphone or tablet, using the new Airbase app. Functionality covers on/off, temperature, zone control, fan speed, and 24-hour timer. Daikin Airbase is available for download through the Apple App Store and Google Play.

This article was compiled with contributions by the following:

Daikin: For more on Daikin’s Premium Ducted systems, AirHub touch controller, and Airbase, visit www.daikin.com.au
Earthwool: For product information, support and installation advice, visit www.earthwool.com.au
Knauf: Try Knauf’s online insulation pack calculator at www.knaufinsulation.com.au/home-owners/upgrading-your-home/insulation-calculator

More information

GreenSmart: www.hia.com.au/hia-community/what-we-do/greensmart-program
YourHome: www.yourhome.gov.au/energy/heating-and-cooling