Window Energy Ratings

Energy Efficiency and Compliance with Clause H1

Maximum ventilation

With no fixed panes and blades that open almost fully horizontally (87 degrees) Altair Louvre Windows welcome fresh, natural breezes. These natural breezes reduce the need for power hungry electric air con-ditioning systems, thereby helping to save our fragile environment.

To learn more about the Benefits of Natural Ventilation please read the Breezway Technical Bulletin below.

View/download Benefits of Natural Ventilationsmall-pdf4

Tight Sealing

Altair Louvre Windows have an air infiltration rating that is significantly better than the standard required for residential windows. Tight sealing reduces draughts thereby allowing heating and cooling systems to run more efficiently.

Choice of Glazing

A variety of energy efficient glazing options is available to meet specific requirements. For example, toned glass blades or timber blades reduce the amount of hot sunlight that enters a building. In mixed and the improved insulating properties of low e glass blades offer thermal performance comparable to clear double glazing.

Please read Timber Blade Energy Ratings for more information.

Compliance With Clause H1

Compliance with Clause H1 of the New Zealand Building Code is possible in all Climate Zones when Altair Louvre Windows are used.

Compliance Option 1: Schedule Method

Compliance is shown by ensuring that individual building elements exceed specified minimum performance levels. If the combined total area of louvre windows is 3 square metres or less then there are no R-value requirements. If the combined total area of louvre windows exceeds 3 square metres then the R-value of each window must be 0.26 or greater.

Compliance Option 2: Calculation Method

Compliance is shown by ensuring that the calculated overall insulation level of the building envelope exceeds specific minimum values. Minimum R-values are not specified for any individual element of the building envelope.

Compliance Option 3: Modelling Method

Compliance is shown by ensuring that the modelled energy consumption of the buildingdoes not exceed specified maximum values. Minimum R-values are not specified for any individual element of the building envelope.

R-Values of Altair Louvre Window Systems

If a window system supplier has not had their Altair Louvre Window System rated according to the New Zealand Window Efficiency Rating System (WERS) then generic window ratings from NZS 4218:2009 must be used.

View/download Energy Efficiency and Compliance with Clause H1small-pdf4