A FENSA certificate is effectively a guarantee that the windows installed within a property meet building regulation standards at the time of their installation. As a result, this means they will have been registered with the local authority as being fully compliant.

FENSA certificates are provided when a FENSA registered tradesman installs new windows or doors.

The benefit of a FENSA certificate is that they can be produced by the contractor themselves, rather than having to arrange and pay for an inspection by a local authority building control officer.

FENSA certificates work much the same as other forms of building regulation compliance certificates.

Having these certificates to hand can be critical when selling a property as they help avoid delays in the house selling process.

What is FENSA?

FENSA, or the Fenestration Self-Assessment Scheme was created by the Glass and Glazing Federation after authorisation by the UK Government in April 2002.

This was in response to changes in building regulations that came into effect on 1 April of that year. These changes required that any new double-glazed window, door which is more than half glass, or rooflight complies with several requirements. These include meeting thermal standards.

FENSA is a register of UK based accredited window fitters and double glazers. It regularly assesses it’s registered members to ensure that skills, competence and compliance with building regulations are maintained.

FENSA is one of several Government approved competent persons schemes. This means FENSA registered tradesmen are qualified to produce FENSA certificates for work they have completed.

This means they are essentially signing off their own work for building control purposes.

All FENSA registered companies’ warranties come with insurance. This means all customers are protected even if their installer ceases being in business.

How to get a FENSA certificate for my windows

The most common way to get a FENSA certificate is to have one given to you by your FENSA registered glazier or window fitter.

This is standard practice for FENSA registered tradesmen, who will provide a physical copy of this certificate upon the completion of a piece of work.

FENSA certificates are valid for as long as the window lasts.

Note that FENSA certificates are only suitable for work that does not involve changes to the footprint of the property. Any windows installed during work which changes the footprint will have to be registered with building regulations directly.

What does a FENSA certificate look like?

What is a FENSA certificate

A FENSA certificate is a one page document that confirms a number of important points. These include the full name of the firm that has carried out the installation and their FENSA registration number. It also details the buildings regulation standards that have been met during installation. Finally, the certificate confirms the various works carried out and the date of the works so that any new buyer knows when this was done.

Can I sell a house without a FENSA Certificate?

If your property has not had any new windows installed since 2002, you will not need a FENSA certificate when selling it.

However, when selling a property which has had windows installed or replaced since 2002, your buyer’s solicitor will ask for a FENSA certificate. This forms part of gathering important documents as you go through the conveyancing stages.

If you can provide this certificate it will show your buyer and their conveyancer the windows were installed in compliance with building regulations.

How to get a FENSA certificate retrospectively

If you cannot provide a valid FENSA certificate you will need to have all windows, rooflights, or mostly glass doors installed after 2002 inspected and signed off on by a building control officer. This process is called regularisation.

Providing the work was carried out to the required standard, the building control officer will provide you with a retrospective building regulation compliance certificate. These certificates can cost as much as several hundred pounds.

If the officer finds the windows are not compliant with building regulations, they will insist the work is rectified before a certificate can be issued.

Alternatively, as a seller you can buy indemnity insurance to cover the cost to the buyer of any losses incurred if the local authority takes enforcement action.

If you know a property has a FENSA certificate, but cannot find it, you can visit the FENSA website and get it from there.

FENSA keeps a record of all certificates issued and will send you a copy of your certificate at a cost of £25.00. The certificate should then arrive within 14 days.

Note that FENSA certificates are transferable between people so if you buy a house with FENSA certified windows, the certificates should come with it and remain valid until you sell it.

Can you self-certify FENSA?

Unfortunately for budding DIY experts you cannot get FENSA certificates for self-installed windows.

This is because FENSA is a registration body for trade professionals only. Unless you are a professional glazier or window fitter you will not be qualified to join.

If you have installed your own windows you will need to apply for building regulation approval. This could take some time to arrange as you will have to complete the application form and wait for an appointment for the inspection.

How much does a FENSA certificate cost?

If you are having windows installed by a FENSA certified fitter the FENSA certificate should be included in the price of the work.

Alternatively, if you have lost your FENSA certificate, you can buy a replacement for £25.00 from the FENSA website.

You cannot buy a FENSA certificate for non-FENSA installed windows or doors. This must be registered through building control and can cost several hundred pounds.

What is CERTASS?

CERTASS is an alternative competent person scheme much like FENSA but run by a different organisation.

FENSA has been around for longer, so it is better known, but both organisations keep registers of competent glaziers.
Tradesmen registered with CERTASS can produce CERTASS certificates which work in exactly the same way as FENSA certificates.

Other competent persons schemes for the replacement of windows and doors in the UK include:


In summary

FENSA certificates, or certificates from other similar competent person registration schemes are important warranty documents when it comes to selling a house.

As all FENSA glaziers are registered with a government approved competent persons scheme, they can produce certificates which work as valid building regulation compliance certificates.

If you intend on selling a property having these certificates to hand can be extremely useful for two reasons. You will be able to avoid either having to pay for a buyer’s indemnity insurance or having to have a building control officer around to check and sign off on the work.

Has this article been helpful? Let us know by leaving a short comment below.