What Is a CP12? Landlord Gas Safety Certificates Explained

If you're a landlord in Leeds, you've probably heard the term "CP12" thrown around — usually in the same breath as "gas safety certificate." They're the same thing. CP12 is just the old form number that stuck as industry shorthand, and it's become the name everyone uses even though the official term is a Landlord Gas Safety Record.

What does a CP12 actually cover?

A Gas Safe registered engineer checks every gas appliance in the property — boiler, gas fire, gas cooker, gas hob — along with the pipework, flues and ventilation. They're checking for gas tightness, that flues are clearing properly, ventilation is adequate, and that safety devices are working correctly. If anything's unsafe, it gets flagged, and in some cases the engineer has to disconnect the appliance on the spot.

How often do you need one?

Every 12 months, without exception, for any rented property with gas appliances or a gas supply. This is a legal requirement under the Gas Safety (Installation and Use) Regulations 1998 — it isn't optional or best-practice, it's the law. You must also give tenants a copy within 28 days of the check, and to new tenants before they move in.

Who can issue a CP12?

Only a Gas Safe registered engineer. Not a general handyman, not a plumber without the right qualification — specifically an engineer registered on the Gas Safe Register for the type of appliance being checked. You can verify anyone's registration on the official Gas Safe Register website before they set foot in a property.

What happens if you don't have a valid CP12?

• It's a criminal offence, with unlimited fines and potentially imprisonment for serious cases
• You may be unable to serve a valid Section 21 (no-fault eviction) notice without one on file
• Landlord insurance can be invalidated if a gas incident occurs without a current certificate
• Letting agents and mortgage lenders will often require proof before renewing terms

None of this is designed to be complicated — it's a straightforward annual visit, usually 20–30 minutes per appliance, and most landlords just build it into the calendar alongside other property checks. If you manage several properties, it's worth booking them together where possible; most engineers, us included, offer better rates for multiple properties on the same day.