Let’s talk about ‘Passive Design’

Most people have heard of passive solar heating but what about passive cooling?

The Building Code of Australia defines Perth’s climate zone as “Warm Temperate” and it is important to consider both when designing your new home.

We’ve broken down some of the concepts into an easy-to-understand summary below, so you can make sure you’re building your home at Wentworth West in a way that maximises passive design principles. This will reduce your running costs and will also help the environment.

What is passive solar heating?

Passive solar heating is the least expensive way to heat your home. Put simply, design for passive solar heating aims to keep out summer sun and let in winter sun while ensuring the building’s overall thermal performance retains that heat in winter but excludes it and allows it to escape in summer. Passive solar design also depends on informed, active occupants who remember to open and close windows and isolate zone spaces, for example, each day.

house plan — Source - YourHome. Australia's guide to environmentally sustainable homes

Passive solar heating requires careful application of the following passive design principles:

northerly orientation of daytime living areas;
passive shading of glass (eaves) and selection of appropriate glazing;
appropriate areas of glass on northern façades;
thermal mass for storing heat (concrete or tiled floors work well); and
insulation and draught sealing (your builder provides ceiling insulation but what about upgrading to some cavity insulation as well?).

What is passive cooling?

Passive cooling is the least expensive means of cooling a home in both financial and environmental terms. Some level of passive cooling is required in every Australian climate at some time of the year.

We have a long summer in Perth, so incorporating these principles into your new home is extremely important.

Heat gain can be minimised by:

shading windows, walls and roofs from direct sunlight. In particular, minimizing the use of windows on your Eastern and Western boundaries works very well;

sun penetration — Source - YourHome. Australia's guide to environmentally sustainable homes

using lighter coloured roofs to reflect heat instead of darker colours that store heat;
using insulation and buffer zones to minimise conducted and radiated heat gains – garages and covered outdoor living areas facing East and West do a great job; and
making selective or limited use of thermal mass to avoid storing daytime heat gains.

To maximise heat loss, use the following natural sources of cooling:

positioning windows and openings to enhance air movement and cross ventilation;
choosing climate appropriate windows and glazing;
shading windows, sun exposed walls and roofs where possible;
installing and correctly positioning appropriate combinations of insulation; and
using roof spaces and outdoor living areas as buffer zones to limit heat gain.

Source – YourHome. Australia’s guide to environmentally sustainable homes

Building a sustainable home isn’t hard although there are many things to consider and lots of options out there to achieve great results. However, the wider your block is, the easier it is to benefit from passive design principles. The extra space you have around your home gives the sunlight more opportunities to enter your home and brighten up your living space during the day.

At Wentworth West we offer a wider than average block to allow you to make the most out of passive design and to help you save money. If you’d like to find out more, contact our Sales Manager Rod Wright on 0407 945 834 or sales@rnoble.com.au, and he can answer any other questions you may have.