What are energy efficient windows?

Windows that help to contain and conserve heat within the home, by keeping out wind and rain and resisting condensation, while at the same time allowing natural ‘free’ energy – the warmth of the sun – to heat the home.

What is a Window Energy Rating?

Window Energy Ratings use an A-E ratings guide. This ratings label can be used by you to make more informed choices about the energy efficiency of the windows you are buying.

All our products are produced in Ireland and are A-Rated Energy Efficient.

So how do you know if a window is Energy Efficient?

Energy Rated Windows are easy to recognise – just look for the labels! If the window does not have a BFRC (British Federation Rating Council) or National Standards Authority of Ireland, (NSAI) energy-rated certificate, it’s not a registered Energy Efficient Window. NSAI’s WEP (Window Energy Performance) Certificate displays an overall energy rating (similar to the Building Energy Rating BER label) for a defined window and window-frame assembly that helps consumers to make an informed selection.
why choose paul harris windows and doors kerry

How are windows rated?

Each window rated by NSAI has a unique label. This label will display the following information:

  • Rating level – A, B, C, etc.
  • Window U-value (thermal transmittance), e.g. 1.4 W/(m2.K)
  • Effective heat loss due to air penetration (air leakage) as L, e.g. 0.01 W/(m2.K)
  • Solar heat gain (solar factor), e.g. g = 0.43

The Rating Index for each window assembly is derived by combining Uwindow, gwindow and the Lfactor.

This will determine how well a product will perform the functions of:

  • Containing and conserving heat within your building in the winter.
  • Keeping out the wind.
  • Keeping your building cool in summer.

Get a Free Quote

Get in touch with us by filling out your details below. Please fill in all fields and we will get back to you as quickly as we can.

Submit request!