Building regulation changes coming June 15th 2022

Published: Thursday 10th March 2022 | Categories: News

We always strive to give our customers the best and most update-to-date information that can have an impact on their home improvements. Beginning June 15th 2022, the government will be updating their building regulation documentation which will have an impact on installations going forward. As a customer at Elglaze, we will always ensure your home improvements meet our high standards and also those of the governing bodies who put these regulations in place. There’s nothing you need to worry about because we take care of it all for you.

The following details are an overview of the changes made being made to building regulations on June 15th 2022:

Approved Document F – Ventilation

With regards to existing windows with trickle vents already in place, there is no discernible difference to the current regulations, that is:

  • The replacement vents cannot be smaller than the ones in the window that is being replaced
  • If the size of the trickle vent in the windows being replaced is not known then the replacement trickle vent should be sized as such:
  1. Habitable Rooms and Kitchens – Equivalent Area of 8000mm²
  2. Bathrooms (with or without a toilet) – Equivalent Area 4000mm²


  • They must be controllable
  1. When replacing existing windows that do not currently have trickle ventilators the base position is that: Trickle ventilators should be installed as below:
    • Habitable Rooms and Kitchens – *equivalent area of 8000mm²
    • Bathrooms (with or without a toilet) – *equivalent area 4000mm²

If the property has “continuous mechanical extract ventilation”

  1. Trickle ventilators with a minimum *equivalent area of 4000mm² should be installed in any replacement windows which are not in wet rooms (e.g. bathrooms, kitchens, utility rooms)

If it can be demonstrated that they comply with the requirements, “other ventilation provisions” may be used.

*If it is not technically feasible to adopt the minimum equivalent areas set out then trickle vents with the closest possible equivalent area should be used.

You can download the Approved Document here from the government website.

Approved Document L – Energy Efficiency

The thermal performance requirements of windows and doors are changing. All replacement windows and doors must:

  • Be no worse than what is being replaced
  • Either achieve a whole window or door value of *1.4W/m²K or:
    1. (Windows) have a Window Energy Rating of B or better
    2. (Doors with a glazed area greater than 60%) have a Door Set Energy Rating of C or better
    3. (All other doors) have a Door Set Energy Rating of B or better

*For timber windows a whole window u-value of 1.6 W/m²K is acceptable

It should be noted that these changes mean that the “Default Method” (PVCu or 60mm softwood/70mm hardwood frames, soft coat low e glass, 16-20mm warm edge spacer bar and 90% argon gas) used by many FENSA installers in the past will cease to be acceptable except in the case of timber windows.

You can download the Approved Document here from the government website.

Approved Document O – Overheating

Approved Document O is a new regulation introduced to mitigate the risk of overheating and is only applicable to new dwellings. The aim is to limit Solar Gain and remove excess heat.

As AD O only applies to new dwellings it will not be applicable when working on installations that require a FENSA certificate however please ensure you are aware of the changes made when working on new build projects.

You can download the Approved Document here from government website.


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