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Replacement windows & doors

Building regulations apply to all replacement glazing, including thermal performance and other areas such as safety, air supply, means of escape and ventilation.

When the time comes to sell your property, your purchaser’s surveyors will ask for evidence that any replacement glazing installed after April 2002 complies with the new building regulations.

Proving compliance

There are two ways to prove compliance:

FENSA and Certass allow installation companies, which meet certain criteria, to self-certify that their work complies with building regulations. They inform local authorities of all completed installations and issue certificates to the householder.

If you are a householder

Before you sign a contract to buy replacement glazing, be sure to ask whether the installer is able to self-certify. If not, they, or you will need to make an application to us and pay any relevant charge.

Please note: as the owner of the property, you are responsible for making sure the work complies with building regulations.

For more information go to the Glass and Glazing Federation website.


To apply to us for a completion certificate, you will need to fill out a replacement windows application form and pay a fee.

Building notice for replacement windows

Domestic • Residential • Retail • Industrial • Educational • Health care • Offices • Commercial • Mixed use