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Sydney’s window manufacturer supplying low u-value double glazed windows and doors


The U value of a window or door is a measure of thermal transmittance. It’s used to convey how heat is transmitted through the door or window. A good performing window has a low U Value. U Values for Ecoline’s tilt and turn windows, by design, are better. As is their airtightness.

Generally, the lower the U-Value of a window or door the better. Low U-Values indicate that a window will perform well in maintaining the indoor temperature of a customer’s home.


U-Value Measurements

For windows, there are some specifics that differ when making U-Value measurements compared to other surfaces, these include:

1. Ug Value = Which measures the thermal performance of the glass.

2. Uf Value = Indicates the thermal performance of the window frame.

3. PSIG = Which indicates the thermal performance of the frame spacers.

These factors combined give you the final U-Value of your window.


For more information about Ecoline Windows and Doors, get in touch.