FENSA

Windows and glazing · Replacement window and door competent person scheme

FENSA assesses installers for eligible replacement windows and doors and arranges Building Regulations compliance certification for work within its scheme. It is not a product brand or a general building warranty.

Checked November 2026Official sources below.

What it covers and whether it is required

Its self-certification route applies to qualifying work in England and Wales. Compliance with Building Regulations is required; using FENSA is one route. New builds, extensions and work outside the scheme need the appropriate alternative route.

Joining requirements and costs

Approved installers are assessed regularly. Applicants accept the scheme rules, provide the required business information and undergo the relevant assessment. Check the current rules for insurance-backed guarantees and the exact installation categories before joining.

Check the current fees with FENSA before applying. Ask whether the quotation includes application, assessment, renewal and any per-job charges. Use published fees or ask for a written quotation.

What it means for homeowners

Check the installer through FENSA and agree that an eligible job will be notified. Keep the FENSA certificate and the separate insurance-backed guarantee paperwork. FENSA explains that the compliance certificate is not itself a guarantee and does not cover every dispute about the contract.

How to check a claim

Official member, card or certificate check: FENSA.

Match the record to the named person or contracting business. Check the current scope, not just a logo on a van or an old certificate. If the public record does not show the detail you need, ask the body to confirm it before appointing the business.

Where the scheme applies

England and Wales for the self-certification service described here. Scotland and Northern Ireland have their own building control requirements.

Common questions

Is the FENSA certificate the same as an insurance-backed guarantee?

No. The certificate concerns Building Regulations compliance. The guarantee insurance is a separate policy with its own insurer and terms.

How do I check FENSA status?

Use the official verification service linked in this guide. Match the person or legal business name, current status and relevant work category. For a guarantee, check the document issued for your contract as well.

Official sources

Sources checked November 2026. Scheme rules can change; confirm current requirements before applying or signing a contract.