As the whole industry should be aware by now, the revised Building Regs Approved Document L (ADL) came into force on 15 June, setting new notional and limiting U-Values for windows and doors in both new build and replacement settings.
AluK now offers HI versions of all our key products so that our customers can easily comply with the new values, and we are continuing our communications campaign designed to ensure that fabricators, installers and specifiers of AluK systems all understand the changes and their individual obligations.
There were a couple of omissions in the original release of ADL relating to the sizes of windows and doors that can be used for the U-Value assessments, and industry trade bodies including the GGF and the CAB had been lobbying the government to address these.
Their hard work has paid off and we have now been notified of some useful changes to both the standard sizes and the configurations.
For windows, a ±25% tolerance has been added to the standard 1.23m width allowed and a -25% tolerance added to the standard 1.48m height, along with the option to use either the actual configuration of the window or one of three standard configurations with fixed or opening lights for U-Value.
For doors, there are now two standard size options, making it possible to assess the larger door types such as folding, sliding and inline sliding doors which were not previously accounted for. So, as well as the actual size and configuration of the door being installed, you can now calculate the U-Value based on dimensions of 1.23m (±25%) wide x 2.18m (±25%) high for doors up to 3.6m2 and 2.00m (±25%) wide x 2.18m (±25%) high for doors over 3.6m2.
Our team can provide advice on any aspect of Part L compliance and there is a dedicated information resource at: https://www.alukgb.com/learning/fhs