If you own a rental property with gas appliances, you've almost certainly heard of a CP12. But a lot of landlords aren't entirely sure what it is, what it covers, or what happens if it lapses.
Here's everything you need to know.
What is a CP12?
A CP12 — formally called a Landlord Gas Safety Record — is an official document confirming that all gas appliances, pipework and flues in your rental property have been inspected and are safe to use.
It's issued by a Gas Safe registered engineer after a safety check, and it's a legal requirement under the Gas Safety (Installation and Use) Regulations 1998.
What does the inspection cover?
A gas safety check covers:
- All gas appliances in the property (boiler, gas hob, gas fire)
- Gas pipework and connections
- Flues and ventilation
- Pressure and flow rates
- Safety devices and cut-offs
- Carbon monoxide risks
The engineer checks each appliance is safe, operating correctly, and not posing a risk to tenants.
How often do I need one?
Every 12 months, without exception.
The CP12 certificate you receive will include an expiry date. Renewal must happen before that date — not after. Letting it lapse, even by a day, puts you in breach of legal requirements.
Who can issue a CP12?
Only a Gas Safe registered engineer. This is a legal requirement — it cannot be carried out by an unregistered tradesperson, however experienced they are.
You can verify any engineer's registration at the Gas Safe Register website.
At WaterHeatPower, we're Gas Safe registered and carry out CP12 inspections across Hemel Hempstead, Ealing, and NW London. We issue the certificate the same day and provide a digital copy for your records.
What happens if I don't have one?
The consequences of not having a valid CP12 are serious:
- A fine of up to £6,000 per offence
- Up to six months in prison
- Invalidation of your landlord insurance (most policies require a valid certificate)
- Inability to serve a Section 21 notice — courts have refused eviction notices where landlords couldn't produce a valid CP12
More importantly, an uninspected gas appliance is a genuine safety risk to your tenants.
Do I need to give a copy to my tenants?
Yes. You must:
- Give your existing tenants a copy within 28 days of the inspection
- Give new tenants a copy before they move in
- Keep a copy yourself for at least two years
Can I combine it with a boiler service?
Yes — and it often makes sense to. A boiler service and CP12 check can be carried out in the same visit. The service keeps the boiler running efficiently and maintains any manufacturer warranty; the CP12 keeps you legally compliant.
If you manage multiple properties, we can schedule all your annual checks to align, so nothing slips through the cracks.
If you need a CP12 inspection in Hemel Hempstead, Ealing, or NW London — get in touch. We'll arrange a time that works around your tenants, provide the certificate on the day, and keep a record against each property for future reference.