FENSA
The UK's main competent-person scheme for replacement windows and doors. FENSA-approved installers can self-certify that their installations comply with the Building Regulations, and installations come with a certificate you'll need when selling your home.
Verify on the official register →
Based on public register entries and source listings collected up to 11 Jul 2026. Not an official membership count.
Check a specific trader
Thinking of hiring someone? Confirm their current FENSA status on the official register, then run their name through our Cowboy Checker to see their reviews, credentials and company details in one place.
Where FENSA holders are
- London
- Maulden Bedfordshire
- Benfleet Essex
- Enfield
- Sutton
- Gravesend Kent
- Brentwood Essex
- Cambridge Cambridgeshire
- St. Albans Hertfordshire
Trades that hold it
Window / Door Fitter · 254Builder · 55Building Completion Contractor · 35Carpenter / Joiner · 17Building Services Contractor · 8Roofer · 6Property Developer · 3Locksmith · 3Civil Engineering Contractor · 2
FENSA holders with review evidence
These businesses hold a current FENSA entry and have customer reviews we can show. This is a small slice of all holders, not the register itself.
Common questions
What is FENSA?
The UK's main competent-person scheme for replacement windows and doors. FENSA-approved installers can self-certify that their installations comply with the Building Regulations, and installations come with a certificate you'll need when selling your home. (Certification scheme.)
How many traders hold FENSA?
We track 435 traders with a FENSA entry, based on register and listing data collected up to 11 Jul 2026. This reflects the public entries we have collected, not necessarily the scheme's complete membership.
How do I check whether a specific trader holds FENSA?
Check the official register at https://www.fensa.org.uk/, or look the trader up on MyTrustedTraders. Profiles show the credentials we have found for them, alongside reviews and other public evidence.
Keep checking
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We show what the public sources say, with dates. A listing here is not an endorsement, and absence from our data does not mean a trader is unregistered. Always confirm current status with the scheme before you hire.