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Why Choose Us

  • Work completed very quickly and efficiently with no damage to walls or cills, we are very pleased with finished product.

  • N. Gallagher, Co Sligo

Energy Efficiency


W001_005-TJ-Grady-Energy-Rating-Chart_A-135x300Our Windows are independently tested by NSAI (National Standards Authority of Ireland) under the Window Energy Performance (WEP) scheme.

We are the first company in Ireland to receive WEP certificates for our A –  Rated windows.


Advantages of A- Rated Windows

  • Reduces the amount of energy required to heat your home
  • Saving you money on heating bills
  • Reduces your carbon footprint



What is Energy Efficiency?Energy-Efficiency-banner-236x122
Energy efficiency in windows, is a windows ability to keep heat in and the cold out, and allow the sun’s solar radiation (heat) to enter your home.

It is a combination of three factors:

  • U-Value (ability to keep heat in)
  • Solar Factor (ability to let the sun’s heat in)
  • Air Leakage (ability to keep cold air out and warm air from escaping)

These three factors contribute directly to how much it will cost to heat your home.



What is a U-Value?
A U-Value is the measure of the rate of heat loss through a material, the lower the U-Value the less heat is needlessly being wasted through your windows.

Casement-GRN-copy-173x300How important is the frame?

Window Frame uPVC Elegance Aluminium
Glass U-value  0.6 0.6
Overall Window U-Value   0.8 1.2


The Aluminium frame means the window 50% worse than with a uPVC frame.

How is it calculated?
It is measured as the amount of heat lost through a one square meter of material for every degree difference in temperature either side of the material.

Glass and Glazing Federation (GGF) have an Energy Saving Calculator which may help you determine the savings you can achieve when changing or selecting your windows.

The Irish Building Regulation U-Value for a Window is 2.2

For more information on U-Values, Energy Efficiency and Sustainable Energy, please visit Sustainable Energy Authority of Ireland (SEAI)


Solar Factor (or Solar Gain or G-Window)

What is Solar Gain?
It is the increase in temperature in a space, object or structure that results from solar radiation (sunlight). The amount of solar gain increases with the strength of the sun and with the ability of any intervening material to transmit the radiation.

How is it calculated?
The higher the Solar Factor the more heat that is transmitted through the glass into your home.



Glazing-copy-150x150How it is important?

The use of high Solar Gain glass (Low-Iron Glass) needs to combine a low U-Value so that you retain the heat in your home.

The U-Value is the most important factor as you will loose heat through your windows all time and solar gain is only available during daylight hours and is most effective during the hottest months of the year, when you really don’t want it.

Air leakage

What is Air leakage?
It is the amount of air that passes from one side of a material or structure to the other.

How is it calculated?
It is calculated by measuring the amount of air in cubic meters that passes through a window at a specified atmospheric pressure. This is converted into the amount of heat lost and represented in Watts per Meter Squared per Degree Kelvin (W/m²K).

Is it important?
For Building Energy Ratings (BER Certs), buildings and therefore windows are tested to 50 Pascals of pressure. NSAI (National Standards Authority of Ireland) insist that all windows tested under their Window Energy Performance scheme are tested to 600 Pascals of pressure, far exceeding building regulations.


Our Casement type uPVC Elegance windows have an effective air leakage of zero, where as, it is almost impossible to manufacture a Vertical/Traditional Sash type window with an air leakage of zero.

  • Very happy with everything, very good work and nice lads to deal with.

  • J. Horgan, Co Limerick

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Grady Joinery, Charlestown, Co. Mayo, Ireland. E:     T:+353(0)949291000