Sealed unit glass U value suppliers refer to two types of measurement for insulation.
Glass U value
Centre pane of glazing this is exactly what it says the “U” value is measured in the centre pane of the glass.
Frame value is the “U” value of the frame.
The measurement that should be used is the overall frame.
The overall frame “U” value is a combination of the centre pane glazing and the frame value.
The glazing has a better “U” value than the frame. So dependent on the frame style and the frame size you can see the overall frame “U” value will change. Many suppliers will tell you their doors have a “U” value the same for all doors this is wrong each design has a different amount of aluminium exposed to the elements and whenever the size of the door is changed the exposed aluminium in bifold doors also changes and so does the “U” value.
Remember the lower the “U” value the better the glazing and insulation of the bifold doors or windows. Improving the “U” value like all things in life when you upgrade will cost a little more.
We offer glazing down to as low as 0.7 “U” value this is expensive glass. I suggest you opt for at least 1.2 or 1.1 “U” value. You can add self cleaning glazing or tinted solar control glass to your bifold doors U value.
Building control currently require an overall U value of 1.8 bifold doors U value using the best centre pane glazing of 0.6 u value can achieve an overall U value of 0.9 U value. Building control will keep on improving the requirement for low loss of heat retaining the maximum amount of heat in the home.
Currently we are offering a special offer of triple glazing with a centre pane value of 0.6 U value.