Selling your house and realizing you have lost your FENSA certificate can cause serious panic. Without it, your buyer’s solicitor can delay the entire property chain, putting your completion date at risk. I am going to show you exactly how to solve this paperwork nightmare quickly and cheaply.
Do you actually need a FENSA certificate to sell?
If you are selling a UK property with replacement double glazing installed after 1 April 2002, your buyer’s solicitor will demand a FENSA certificate. This document tracks and proves that your new windows and doors comply with building regulations, meet energy efficiency standards, and are officially registered with your local authority.
If you have lost your certificate, do not panic. You can easily order a replacement online for £25, or your solicitor can arrange an inexpensive indemnity policy to keep the sale moving.
What a FENSA certificate covers (and what it doesn’t)
FENSA stands for the Fenestration Self Assessment Scheme. It regulates the double glazing industry across England and Wales. When an installer is registered with them, it means they can self-certify that their work complies with building regulations instead of paying for a local authority building control inspector to visit.
However, FENSA does not cover every piece of glass on your property.
What FENSA covers:
- External window replacements
- External door replacements (where more than 50% is glazed)
- Roof lights and skylights
What FENSA does not cover:
- Conservatories and porch installations
- New extensions or newly built homes
- Detached garages or outbuildings
- Repairs to existing windows, like replacing a blown double glazed unit
If you are missing paperwork for a conservatory or a porch, you can stop stressing. FENSA certificates never existed for those structures in the first place. If you are planning broader renovations, you should review our guide on interior property regulations to stay fully compliant.
Do I Need a FENSA Certificate?
Use my interactive tool below to check if your specific installation actually requires a certificate for your house sale.
FENSA Requirement Checker
Answer three quick questions to see if missing paperwork is going to delay your house sale.
How to order a replacement FENSA certificate online
If you know the windows were installed correctly by a registered company but you have simply misplaced the paperwork, retrieving it is remarkably simple. You do not need to hunt down the original window company.
You can go straight to the official FENSA certificate search portal online. Enter your postcode and house number to search their database. If the installer logged the work correctly, your property record will appear immediately.
Ordering a duplicate certificate costs £25. It will be emailed to you as a digital document in under ten minutes.
Retroactive compliance: Double glazing indemnity policies explained
What happens if you look up your property online and nothing shows up? This typically happens if the previous owners used an unregistered handyman, did a bit of uncertified DIY, or if the window company went bust before registering the job.
If your buyers are pushing to exchange contracts and you have no paperwork, you can bypass the panic entirely by using a double glazing indemnity policy.
Your conveyancing solicitor can arrange this insurance policy for a one-off premium, which usually costs between £20 and £50. The policy protects the new buyer against the financial cost of any potential local council building control enforcement action.
In my 20 years handling property sales, I have found that solicitors routinely accept these policies to keep a chain from breaking. Just keep in mind that you can only purchase an indemnity policy if the windows were installed at least 12 months ago and the local authority has not already issued an enforcement notice.
FENSA vs. Certass: Are they the same?
When you are digging through your old household files, you might find a certificate from Certass instead of FENSA. I have had readers panic because they did not have the exact FENSA brand paperwork, but there is no need to worry.
Certass is a legally identical competent person scheme authorized by the government. It operates under the exact same building regulations framework as FENSA. If you hand your buyer’s solicitor a Certass certificate, it carries the exact same legal weight as a FENSA document. It proves your replacement window costs were spent on a legally compliant, energy-efficient installation.
If your windows required significant structural modifications during installation, such as widening an opening or altering a load-bearing lintel, ensure you also check our guide on structural building compliance to confirm your paperwork is fully in order.
