Landlord Gas Safety Certificate (CP12) Explained: What London Landlords Need to Know
If you let a property with any gas appliance, an annual Gas Safety Certificate isn't optional. Here's what it actually covers and how the renewal cycle works.
What a CP12 Actually Is
The Landlord Gas Safety Certificate — commonly referred to by its old form number, CP12 — is the record confirming that every gas appliance in a rented property has been checked and found safe by a Gas Safe registered engineer. It covers the boiler, and any gas fire, hob or gas water heater the tenancy includes. It is a legal requirement for landlords in England and Wales, not a recommended extra.
What the Inspection Covers
The engineer checks each gas appliance for safe operation, correct ventilation, and satisfactory condition, along with the associated flues. Anything found to be unsafe is flagged, and in some cases an appliance may need to be turned off or capped until it's fixed. The certificate records the outcome of each check individually, not just a single pass or fail for the property as a whole.
The 12-Month Cycle, and Why Timing Matters
A Gas Safety Certificate is valid for 12 months from the date of inspection. The next check can be carried out up to two months before the current certificate expires without losing time from the original renewal date — which is a useful detail if you want to align the check with, say, a tenancy changeover or the start of the heating season. Letting the certificate lapse, even briefly, means letting the property without a valid one, which is a breach of your legal obligations.
Getting the Certificate to Your Tenants
You're required to give existing tenants a copy of the current certificate within 28 days of the check, and to give a new tenant a copy before they move in. Keeping a simple record of when each certificate was issued and given to the tenant is worth doing, particularly if you manage more than one property.
Combining It With Your Boiler Service
Because a Gas Safety Certificate inspection covers the boiler anyway, many landlords combine it with the annual boiler service in a single visit. It's not required to do it this way, but it usually saves arranging a second appointment and a second period of tenant access.
Frequently asked questions
Is a Gas Safety Certificate the same as a boiler service?
No, though they're often combined in one visit. A boiler service is a maintenance check on the boiler itself. A Gas Safety Certificate (CP12) is a compliance inspection covering every gas appliance in the property, required annually by law for landlords.
What happens if my Gas Safety Certificate expires while a tenant is in the property?
Letting the certificate lapse means the property no longer has a valid inspection covering its gas appliances, which is a breach of your legal obligations as a landlord and can also affect your ability to serve certain eviction notices. Booking the renewal before expiry avoids this.
Do I need a new certificate for each new tenant?
You need a valid, current certificate to give to any new tenant before they move in. If the existing certificate is still within its 12-month validity, you can give a copy of that one — a new inspection isn't automatically required just because tenants change.