Certification scheme

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 →

404tradespeople with a FENSA record in the public data we track

Based on public register and directory records collected up to 2 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 record in one place.

Where FENSA holders are

  • UK347 on record
  • GB56 on record
  • London1 on record

Trades that hold it

Window / Door Fitter · 236Builder · 52Building Completion Contractor · 35Carpenter / Joiner · 13Building Services Contractor · 8Roofer · 5Property Developer · 3Locksmith · 3Window / Door Fitter · 2

FENSA holders with review evidence

These businesses hold a current FENSA record and have customer reviews we can show — 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 tradespeople hold FENSA?

We track 404 tradespeople with a FENSA record, based on register and listing data collected up to 2 Jul 2026. This reflects the public records 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 records 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.