Replacement windows and doors in a dwelling are notifiable under building regulations. A FENSA or CERTASS registered installer self-certifies the work and issues you a certificate. Without one, you need a building control completion certificate instead — and buyers' solicitors will ask for one or the other.
Nobody thinks about a FENSA certificate on the day the windows go in. It surfaces years later, when a buyer's solicitor asks for evidence that the windows comply with building regulations, and there isn't any.
At that point you have three options: find the certificate, apply for a regularisation certificate from building control (which means paying a fee and possibly opening up work for inspection), or take out indemnity insurance — which does not make the work compliant, it just protects against enforcement. Buyers increasingly refuse to accept indemnity.
Both are Competent Person Schemes and both are equally valid. There is no meaningful difference from a homeowner's point of view — what matters is that the installer is registered with one of them, and that you actually receive the certificate.
You need evidence that the windows comply with building regulations. That is either a FENSA or CERTASS certificate from a registered installer who self-certifies, or a building control completion certificate. A buyer's solicitor will ask for one of them.
You can apply to your local building control for a regularisation certificate, which may involve a fee and an inspection, or take out indemnity insurance — though indemnity only protects against enforcement, it does not make the work compliant, and buyers increasingly refuse it.
Yes. Both are government-authorised Competent Person Schemes and both produce a valid certificate. What matters is that your installer is registered with one of them.
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