Your choice of windows has a profound effect on your home's energy efficiency. Smart design, orienting for the sun and high levels of insulation go hand in hand with choosing the right joinery. You can reduce your energy bills and maintain more comfortable living conditions in your home when you consider windows and their role in your home's thermal envelope and long term upkeep.

If you're not sure how to choose energy efficient windows here are some useful tips.


Wood window frames are energy efficient, but they require attentive maintenance. If not kept in good condition, they are prone to warping and draughts, creating heating and cooling problems for your home. The Ministry of Social Development cautions that more than 20% of a home's heating can be lost in draughts, forcing homeowners to increase the amount of heating and cooling of their homes. 

"Aluminium joinery is a popular choice as it is a material that can last for long periods of time without replacement and with little maintenance" 

Aluminium windows aren't subject to those kinds of problems, and are more durable and more often cost-effective, to boot. Aluminium joinery is a popular choice as it is a material that can last for long periods of time without replacement and little maintenance. In addition at the end of the product lifecycle, aluminium is 100% recyclable and repeatedly so.

Look for low VOC colour coatings when you consider the colour finishes of your aluminium windows.  For example, Altus Window Systems windows and doors, when powder coated are cured in an oven, release less volatile organic compounds into the atmosphere than other painting methods. In addition, their powder coating is warrantied for 10 years or more.

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Take seasonal variations in sunlight into account when planning the location and size of eaves.


New Zealanders love large windows and ample sunshine, but our sunshine can generate a lot of heat. Direct sunlight can produce the same level of surface heat as a single-bar radiator. That's great in the winter, but during summertime, excessive sunlight can make your home hot and uncomfortable.

The correct orientation of your home on its section topography is very important to maximise the sun. When choosing the size and configuration of windows, take into account variance in the sun's position in relation to different sides of your house between seasons. 

Fixed aluminium louvres, are another method to control solar heat gain. The Highbrook® Louvre range from Altus Window Systems allows you to custom design aluminium louvre blades for your shading. They can be orientated vertically, horizontally or sloped, with the depth (length of blade), spacing and pre-set angle all adjustable to suit where and when you need sunlight. At the last line of defence is your selection of glazing, more about that later.

"Adding insulation to your aluminium windows can help reduce conductive thermal energy loss."


With the wide variances in our climate, there's no better time to address the thermal conductivity that can occur through your window glass and frames. Adding thermally efficient features to your aluminium windows can help reduce heat loss/gain, resulting in a more energy-efficient home all year long.

This can be done with the help of thermal breaks, which serve as a barrier between the interior and exterior window frames on double or triples glazed windows. There are two main forms of thermal break available: a reinforced polyamide strip or a resin-filled channel called a 'pour and de-bridge.' Regardless of which method you go with, the added insulation of your windows and doors will help you achieve a healthier home environment with less heating and cooling requirements.

The Altus Pacific Thermal system features a polyamide strip thermal barrier to combat conductive thermal energy loss. When combining double glaze with Argon gas and a Low-e coating, you can add up to 50% more thermal efficiency to what double glazing alone can provide.

Don't have double-glazed windows in your home? No problem! With the right expert advice you can easily have your current windows retrofitted with double-glazed panes. The retrofitting process is relatively simple and affordable however not all joinery is suitable. We recommend you contact a retrofit industry expert from Dualglaze. 


Increase your thermal efficiency and reduce energy consumption with double-glazed windows.


As discussed above, when you combine thermally enhanced joinery with Low-e glass your windows thermal efficiency could be improved by as much as 50%. Your home will stay warm and cosy, even on the coldest of days. Low-e glass is coated with a low-emissivity film that reflects solar energy while allowing visible light to shine through. 

One of the additional benefits of Low-e glass is that it controls the amount of ultraviolet (UV) rays that enter your home. UV rays can cause damage to your furniture, carpet, artwork, wood floors and other materials over time. Any object that sits in the direct path of UV rays over a long period of time could exhibit noticeable signs of sun damage. 

According to Massey University's Environmental Health Indicators New Zealand team, the nation's remoteness and relatively low pollution levels present less resistance for UV rays. UV light can pass through the atmosphere more easily. As such, the university states that New Zealand's highest UV levels are 40% higher than areas in North America at similar latitudes. 

Low-e Glass can help cut down on UV light in your home even when you have extensive windows and doors.


With the right configuration, aluminium windows can help improve your home's energy efficiency. At the same time, aluminium windows are highly durable and resilient in the face of wind, rain and anything else Mother Nature can throw your way. 

Aluminium windows have a number of options for anyone looking to improve their home's insulative qualities. As a summary, here's what aluminium windows have to offer:

If you're interested in making your home more energy efficient and lowering your heating costs and electric bills, reach out to an Altus Window Systems manufacturer today to learn more about  the right option for your home.






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