Energy Ratings

Beautiful windows and doors are possibly the most complex and interesting elements in the fabric of our homes. They provide light, fresh air and offer views that connect our interior living spaces with the great outdoors.

On the other hand, ordinary windows can also represent a major source of unwanted heat gain in summer and significant heat loss in winter.

Energy efficient windows and doors will help make your home more comfortable, reduce your energy costs and help to create a brighter, cleaner and healthier environment. Wideline have conducted thorough testing across our product range through a NatHERS approved Certified AFRC (Australian Fenestration Rating Council) Simulator and can tailor a solution to meet your energy requirements.

How do energy efficient windows and doors work?

Various factors come into play when determining energy efficiency of buildings, with windows forming only one part of the “whole of house” calculation. Floor plan and design of the house, eave projection, size of orientation of the windows/doors and the amount of cross-flow ventilations are all taken into consideration.

It is important to understand that heat energy can be transferred into or out of your home in two ways – Conduction and Radiation. The energy efficiency of a window system is expressed in terms of how well the window insulates against both.

The U-value expresses how well the window insulates against the transfer of heat through a window or door; it is a measure of conductive heat transfer. The lower the number, the better the window or door performs at reducing the transfer of heat. Timber windows and doors perform better than aluminium, which is a poor insulator due to its high thermal conductivity.

The Solar Heat Gain Coefficient (SHGC) is the amount of heat generated from direct sunlight passing through the glass. During summer the lower the SHGC number, the better the window or door will perform at reducing the amount of heat gain through the glass and thus radiant heat being absorbed into the room. The opposite of this applies to homes in winter where a higher SHGC number is desirable, allowing passive heating via more sunlight to improve the energy efficiency of a home.

What is NatHERS?

NatHERS stands for Nationwide House Energy Rating Scheme. NatHERS enables windows and doors to be rated and labelled for their annual energy impact on a whole house, in any Australian climate.

To participate in NatHERS, window and door manufacturers must obtain energy ratings for their products from a rating organisation that is accredited by the ARFC.

NatHERS is administered by the Dept of Industry, Science, Energy and Resources on behalf of the states and territories. For more information visit the NatHERS website.

Window and door testing is conducted independently of any one manufacturer and acts as a fair, rigorous and credible system for testing performance claims. Accredited AFRC tested windows and doors must meet all relevant Australian standards. The scheme forms part of the quality assurance that smart manufacturers offer their customers. It is all about certified performance.

If you have any questions in regard to energy performance, please contact one of our expert Wideline sales staff who will be able to assist you. Visit a Showroom or call 1300 943 354.