UK landlords are legally required to have every gas appliance and flue in a rented property checked once a year by a Gas Safe registered engineer, and to provide tenants with a copy of the resulting gas safety certificate — commonly known as a CP12 — within 28 days of the check being carried out. New tenants should receive a copy before they move in.
This isn’t optional paperwork. It’s a legal safety requirement under the Gas Safety (Installation and Use) Regulations, and it exists because gas appliances that aren’t properly maintained can be genuinely dangerous.
What a gas safety certificate actually is
“CP12” is the informal name landlords and engineers commonly use for a Landlord Gas Safety Record. It’s the document a Gas Safe registered engineer issues after inspecting all the gas appliances, pipework, and flues in a rented property and confirming they’re safe to use.
It covers things like:
- The boiler
- Gas hobs and cookers
- Gas fires
- Any other fixed gas appliances supplied by the landlord
Appliances that belong to the tenant themselves (bringing their own gas cooker, for example) generally aren’t the landlord’s responsibility to certify, though the associated pipework usually still is.
What the engineer checks
During the inspection, a Gas Safe registered engineer will typically check each appliance for:
- That it’s operating at the correct pressure and gas flow rate
- That safety devices are working correctly and shut off the appliance when they should
- That the flue and ventilation are working properly, so fumes are safely removed from the property
- That there’s adequate ventilation into the room where the appliance is fitted
- That pipework and fittings show no signs of leaks, wear, or damage
- General physical condition of each appliance
If something fails, the engineer will advise on next steps, and in serious cases may need to disconnect an appliance that poses an immediate danger.
Landlord responsibilities at a glance
| Requirement | Detail |
|---|---|
| Frequency | At least every 12 months |
| Who can carry it out | Gas Safe registered engineer only |
| Certificate copy to tenant | Within 28 days of the check |
| New tenants | Copy given before they move in |
| Record keeping | Landlords should keep copies for at least 2 years |
Why this matters beyond the law
Aside from being a legal requirement, annual gas safety checks are one of the simplest ways to catch a developing fault before it becomes dangerous. Gas appliances that aren’t serviced can develop faults that lead to gas leaks or carbon monoxide production, both of which are serious safety risks to tenants. A yearly check by a qualified engineer catches most of these issues well before they become a real hazard.
It’s also worth noting that a CP12 doesn’t replace the value of a full annual boiler service — a service goes into more depth on the boiler specifically, while the gas safety check covers all gas appliances in the property from a safety compliance angle. Many landlords choose to have both done at the same time for convenience.
What happens if a landlord doesn’t comply
Failing to keep up with gas safety checks is a serious matter. In general terms, landlords who don’t comply can face prosecution, and non-compliance can also invalidate landlord insurance policies, leaving the landlord personally exposed if something goes wrong. Beyond the legal risk, it also puts tenants in genuine danger — which is the whole reason the regulations exist in the first place.
Local authorities and letting agents also increasingly expect to see an up-to-date certificate as standard, and many won’t proceed with a tenancy without one on file.
Practical tips for landlords
- Book your annual check a few weeks before the current certificate expires, so there’s no gap in cover if any remedial work is needed
- Keep certificates on file for at least two years, and ideally for as long as you own the property
- Give tenants their copy promptly — don’t wait to be asked
- Use the same Gas Safe registered engineer each year where possible, so they build up a history of the appliances and can spot developing issues more easily
A gas safety certificate is a straightforward, once-a-year piece of compliance, but it protects tenants, protects the landlord’s insurance position, and helps catch small problems before they become serious ones. Eco Flow can carry out landlord gas safety checks and provide a fixed quote before any work begins.