U Values For Doors And Windows

A u value calculated by us should be sufficient to satisfy the requirements of building regulations.

U values for doors and windows.

Typically double glazed windows record a u value of between 1 2 w m k and 3 7 w m k while triple glazed windows are usually rated below 1 w m k. For most energy efficient windows the whole window u factor is higher than the center of glass u factor. U factor u value range between 20 to 1 20. This is desirable in very hot and sunny locations to avoid the greenhouse effect inside a home.

The lower the u factor the better insulated the window. Typical u values on windows and window energy ratings are similar to the familiar energy labels you see on home appliances rated from a the lowest up to g the highest or worst performing. The lower the u factor the better the window is at keeping heat inside this is desirable in colder climates like the northeast. U value is an inverse measure.

In the case of a window it s 1 6 w m2k. To comply with building regulations windows like every other element of your property must meet a certain minimum u value. Some window performance figures are expressed with a u value and others with a window energy rating although the latter has been adopted as the more commonly used. We can advise on how you might achieve the required standard.

According to part l1a of current building regulations a domestic window installation should achieve a u value no higher than 1 4 w m k. A higher u factor allows heat to escape. How is u value determined. This calculated value conforms with bs en iso 10077 part 1.

Improved education and awareness of the cost of heating and cooling that escapes from poorly insulated components and glass panes have led to window and door manufacturers developing energy efficient windows and doors typically labeled r5 u 2 meaning the glass is the most energy efficient possible at a 5 rating and the window or door with all of it s built out components are a 2 which is almost as low as any rating can go remember a 5 is the highest energy rating for r value which is. Window energy ratings provide a simplified method of understanding the energy saving properties of a window. Double glazed windows filled with argon are typically 1 4 w m2k while thicker triple glazed windows can go as low as 0 7 w m2k.