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FENSA Certificates Explained: Do You Need One to Sell Your House?
FENSA Certificates Explained: Do You Need One to Sell Your House?
Category: Buying Guide / Regulations
Reading Time: 5 Minutes
📌 FENSA Explained: The 30-Second Summary
- What is it? FENSA is the gold standard for window compliance. It proves your installation meets Building Regulations.
- Do I need it? Yes, if you replace >50% glass in a window or door. No, if you replace a composite door with little glass.
- Selling? Solicitors will demand this certificate. If you don’t have one, you may need indemnity insurance.
If you are replacing windows or doors in your home in Hampshire, “FENSA” is the one word you cannot ignore. It is not just a logo; it is your legal proof that your windows comply with UK law.
At KJM Group, we believe in total transparency. We have been a FENSA Registered Company since the scheme began. Here is your complete, jargon-free guide to why that certificate matters—and exactly when you need one.
Table of Contents
1. FENSA & Competent Person Schemes
Since 2002, all replacement windows and doors must meet UK Building Regulations regarding thermal performance, safety, and ventilation.
To avoid every homeowner having to pay their local council (like Test Valley or Basingstoke & Deane) to physically inspect every single window, the government created Competent Person Schemes (CPS).
FENSA allows registered companies (like KJM) to “self-certify” that their work meets these strict standards. We handle the paperwork, and you get the certificate in the post.
2. Do I Need a Compliance Certificate?
Not every job requires one. The rules depend heavily on the type of work and the amount of glass.
The Compliance Checker
Action
Replacing frames and glass in existing openings.
Requirement
YES – MANDATORY
Example
Patio doors, French doors, Bi-folds.
Requirement
YES – MANDATORY
Example
Composite front doors or solid panel back doors.
Requirement
NO
⚠️ The 50% Glass Rule
Many homeowners panic when they can’t find a FENSA certificate for their front door. Don’t worry. If the door frame contains less than 50% glass (based on total area), it is exempt from FENSA registration. You do not need a certificate to sell your house in this case.
3. New Builds & Extensions
A very common question we get asked in Andover and Winchester is: “I’ve just built an extension—where is my FENSA certificate?”
🏗️ The “Whole Build” Rule
You do NOT normally need a separate FENSA certificate for windows installed in new builds or new extensions.
Here is why:
- Local Authority Sign-Off: When you build an extension, Building Control (e.g., Hampshire Building Control Partnership) signs off the project as a whole. This inspection covers foundations, walls, and glazing.
- The Proof You Need: Your overall Building Control Completion Certificate for the extension acts as your proof that the windows comply.
4. Help! I’ve Lost My Certificate
This is the most common panic we hear from people selling their homes. If you have lost your paper certificate, don’t worry.
Option 1 (The KJM Way): If we installed your windows, we keep records dating back years. Give our Andover office a call on 01264 359355, and we can often help you locate your contract reference number to aid your search.
Option 2 (The Direct Way): You can order a replacement directly from the FENSA website External (cost approx £25).
5. Can I Do It Myself (DIY) or Use a General Builder?
Yes, but you cannot issue a FENSA certificate yourself.
If you (or a general builder who isn’t CPS registered) install the windows, you are legally required to apply to your Local Authority Building Control before you start work. You will have to pay for them to inspect the installation.
⚠️ The Hidden Cost
Council inspection fees in Hampshire can often cost more than the money you save by doing it yourself. Plus, if the inspector finds the windows aren’t up to code, you may have to rip them out.
6. Frequently Asked Questions
The certificate is valid for the life of the windows. It stays with the property, not the person. However, the Insurance Backed Guarantee (IBG) that typically accompanies it usually lasts for 10 years.
No. Conservatories are generally exempt from Building Regulations (provided they are separated from the house by external-quality doors), so they do not require a FENSA certificate. However, the doors connecting the house to the conservatory DO require one (if they are over 50% glass).
Yes. Never take a builder’s word for it. You can search for any company on the FENSA website to verify their registration number.
Explore Our Home Improvement Hub
Looking for more advice on regulations and renovations? Check out these guides:
Mark Pearce is a highly experienced specialist in the double glazing industry, having built his knowledge from the ground up through hands-on experience in installation, manufacturing, sales, and business management. Beyond his role at KJM, Mark is a keen blogger, writer, and traveller, often sharing insights on the latest innovations in the home improvement industry.
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