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Replacing windows regulations

Find out about how you can comply with regulations when replacing glazing.

Published: 20 January 2021

Last updated: 20 January 2021

When you sell your property, your purchaser's surveyors will ask for evidence that any replacement glazing installed complies with the new building regulations.

There are 2 ways to prove compliance:

  • have a certificate showing that the work has been done by an installer who is registered under the FENSA scheme
  • have a certificate from the council saying the installation has approval under the building regulations

All replacement glazing falls within the scope of the building regulations.

Anyone who installs replacement windows or doors will have to comply with strict thermal performance standards.

Before signing a contract to buy replacement glazing, ask whether the installer is able to self-certify. If not, either they or you will need to make an application to your council for approval under the building regulations, and pay any relevant charges.

One of the main reasons is to reduce energy loss in the home. It is essential to improve the performance of existing buildings, if we are want to meet national and global energy saving targets.

The FENSA Scheme

This is a government-approved scheme, which helps protect both homeowners and traders, to monitor building regulation compliance for the replacement of windows and doors by:

  • inspecting a sample work of every installer
  • inform councils of all completed FENSA installations
  • issue certificates to householders confirming compliance

The homeowner is responsible for ensuring the work complies with the building regulations.

Any installation done by a firm which is not registered to self-certify or done as a DIY project by a householder will need full council approval under the building regulations. 

We will know of all the approved installers in their areas and will be able to identify unauthorised work very easily.

There may be conditions or other additional controls on your property which restrict the types of windows you can install.

You can find out more information at the Glass and Glazing Federation.