What the law requires, what we check, and how to stay compliant.
If you rent out a property with gas appliances, you must arrange an annual gas safety check by a Gas Safe registered engineer and provide a valid Landlord Gas Safety Record (CP12).
Landlords can be prosecuted for non compliance. Penalties can include substantial fines and, in serious cases, imprisonment.
Separately, failing to provide the correct prescribed documents to tenants can also affect the legal possession process (including Section 21 while it exists). If you are unsure, take professional advice.
A Landlord Gas Safety Certificate, officially called a CP12, is a legal document confirming that all gas appliances, pipework, and flues in a rental property have been checked by a Gas Safe registered engineer and are safe to use.
The certificate must be renewed every 12 months.
You can renew a Gas Safety Record up to 2 months before the expiry date without losing any time on the certificate. The new record can be dated from the expiry date of the previous record, provided the check is completed within that window.
This gives you flexibility to schedule around tenant availability without gaps in compliance.
| Item | What We Check |
|---|---|
| Boiler | Safe operation, correct combustion, flue integrity, ventilation |
| Gas cooker or hob | Burner operation, flame failure devices, stability |
| Gas fire | Flue flow, spillage test, combustion |
| Gas pipework | Tightness test for leaks, correct installation |
| Flues and ventilation | Clear, correctly terminated, adequate air supply |
| Safety devices | Working correctly and not bypassed |
If everything passes, we issue the CP12 certificate the same day (in most cases). If we find issues, we explain what is needed and can often fix minor problems during the visit.
A Gas Safety Check is not the same as a boiler service:
| Gas Safety Check (CP12) | Boiler Service |
|---|---|
| Legal requirement for landlords | Recommended but not legally required |
| Confirms appliances are safe | Maintains efficiency and reliability |
| Checks all gas appliances in property | Focuses on the boiler only |
| Typically 20 to 30 minutes | 30 to 45 minutes |
| Issues legal certificate | No certificate unless requested |
Many landlords book both together for convenience. We offer combined appointments.
More detail: Boiler servicing.
The CP12 confirms appliances are safe but does not include:
We recommend combining your CP12 with an annual boiler service. This maintains the boiler and keeps tenants happy with reliable heating.
If we find an unsafe appliance:
We will not leave you stranded. We explain your options and can often return quickly to complete repairs.
If we classify an appliance as Immediately Dangerous, we are legally required to disconnect it. This protects your tenants from carbon monoxide poisoning or gas leaks. Learn more: Carbon monoxide safety guide.
Most landlords book their Gas Safety Check and boiler service together. It is more convenient for tenants and keeps your boiler running reliably. Ask about combined appointments when you call.
If you manage several rental properties, we can help you stay organised:
Call us to discuss your portfolio: 0203 695 3137.
HMO landlords have additional responsibilities. All gas appliances must be checked, including:
The CP12 must cover all appliances in the property. For more HMO guidance, see our HMO landlord’s guide.
Gas safety is just one part of landlord compliance. You also need:
Full breakdown: The London landlord’s essential checklist.
Also see: Why your boiler is a landlord’s biggest risk and opportunity.
We issue CP12 certificates across all London boroughs and surrounding areas. Flexible scheduling including evenings and weekends to suit tenant access.
How long does a gas safety check take?
A typical inspection takes 20 to 30 minutes for a single boiler. Properties with multiple gas appliances (boiler, cooker, fire) take longer.
Can I do the gas safety check myself?
No. By law, only a Gas Safe registered engineer can carry out landlord gas safety checks and issue CP12 certificates.
What if my tenant will not allow access?
You must make reasonable efforts to arrange access. Document all attempts in writing. If the tenant repeatedly refuses, seek legal advice. You cannot be held liable if you have evidence of reasonable attempts.
Do I need a CP12 if there are no gas appliances?
No. If your property has no gas supply or gas appliances, you do not need a CP12. However, you should confirm this in writing and check there are no hidden gas supplies such as capped pipes or old fires.
Is a CP12 the same as a Gas Safe certificate?
Yes. CP12 is the official name for the Landlord Gas Safety Record. It is sometimes called a Gas Safe certificate, gas safety certificate, or landlord gas check. They all refer to the same document.
Fast, reliable CP12 certificates for London landlords. Certificate issued the same day (in most cases).
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