Approved Document L: replacement windows and doors in England
The thermal requirements for replacement windows, doors and rooflights in England, and who is responsible.
What does Approved Document L require?
For replacement windows in existing homes in England, the limiting value is a U-value of 1.4 W/m²K or a Window Energy Rating of band B. Replacement doors have a limiting U-value of 1.4 W/m²K, and replacement rooflights 2.2 W/m²K.
Who is responsible for compliance?
The person doing the work. Replacing windows, and doors that are more than half glazed, is notifiable building work. A registered installer self-certifies through a competent person scheme such as FENSA or Certass; otherwise the work goes through building control.
What do we supply to help?
The glazing and frame can be specified to meet the values for where the job is; the U-value or WER is stated on your quote, and we can provide the product performance data your scheme or building control officer asks for.
What about Wales, Scotland and Northern Ireland?
Each has its own regulations and guidance with different values in places. Tell us where the job is when you order.
This guide is general information for trade customers. The person carrying out the work remains responsible for meeting the building regulations and any planning requirements for the specific job.