FENSA Certificates: Why They Matter When You Sell Your Home
If you've had windows or doors replaced in your {location} property, you should have a FENSA certificate for the work. Many homeowners don't think about this until they come to sell — and by then, a missing certificate can cause delays, extra costs and even reduce your sale price.
What Is FENSA?
FENSA (Fenestration Self-Assessment Scheme) is the government-authorised scheme that allows registered window installers in England and Wales to self-certify that their work complies with building regulations. When a FENSA-registered installer replaces your windows or external doors, they notify your local council on your behalf and issue a certificate confirming compliance.
The scheme covers Part L (energy efficiency), Part N/K (safety glazing), Part F (ventilation) and Part B (fire safety) of the building regulations.
Why Do You Need One?
Under the Building Act, replacement windows and external doors are classed as building work and must comply with building regulations. There are only two legal ways to demonstrate compliance:
- Use a FENSA-registered installer (or equivalent competent person scheme such as CERTASS), who self-certifies the work
- Apply directly to your local council for building control approval before the work starts
If neither of these happened, the installation is technically unauthorised. This doesn't mean the windows are unsafe or poorly fitted — but without proof of compliance, you have a legal gap.
What Happens When You Sell?
When you sell your {location} property, your solicitor will check the building regulations compliance for any replacement windows or doors. If FENSA certificates (or building control completion certificates) are missing, several things can happen:
- The buyer's solicitor raises it as an issue — this is almost guaranteed. Missing certificates are flagged in the standard property enquiries.
- You may need to buy indemnity insurance — this covers the buyer (and their mortgage lender) against the risk of the local council requiring the windows to be removed or upgraded. A policy typically costs £100 to £300.
- The buyer may negotiate a price reduction — particularly if the windows are old and might not meet current standards.
- In worst cases, the sale stalls or falls through — some mortgage lenders are stricter than others about missing certificates.
Can You Get a Certificate After Installation?
If the work was done by a FENSA-registered installer but you've lost the certificate, you can request a replacement from FENSA directly via their website. There's a small fee, and they hold records going back to 2002.
If the installer was not FENSA-registered and you didn't get building control sign-off at the time, you cannot get a retrospective FENSA certificate. Your options are:
- Apply to your local council for a regularisation certificate — they'll inspect the windows and, if they comply, issue a certificate. This typically costs £200 to £400 and there's no guarantee of approval.
- Purchase indemnity insurance to cover the gap — quicker and cheaper, but doesn't prove the windows actually comply.
How to Protect Yourself
When having windows replaced in {location}:
- Always use a FENSA or CERTASS registered installer
- Confirm the installer will register the work with your local council
- You should receive your certificate within a few weeks of completion — chase it if you don't
- Keep the certificate with your property deeds and important documents
Checking an Installer's Registration
You can verify whether an installer is FENSA-registered by searching the FENSA website. This takes 30 seconds and could save you significant hassle and money down the line.
FENSA certificates are one of those things that seem unimportant until you need them. Getting it right at the point of installation costs nothing extra — sorting it out years later when you're trying to sell can be time-consuming and expensive.