What Energy Rating/U-value do my windows or doors need to achieve?
Your required Energy Rating or U-value depends on where in the UK you are installing your windows or doors, and whether the project is a new-build or an existing property. Our requirement calculators help you identify the exact minimum performance needed by simplifying the key glazing-related standards in current building regulations. They provide easy-to-understand guidance based on our interpretation of these requirements, helping homeowners, builders and designers make informed decisions. However, for full accuracy and complete compliance, we always recommend reviewing the official government building regulation documents, which outline all rules in complete detail.
In which country will the windows or doors be installed?
Will the windows or doors be installed into a new-build?
What is a U-value? A U-value measures how easily heat passes through a window or door.
What is an energy rating? Energy ratings combine U-value, solar gain, and air leakage into a single grade.
