Landlord gas safety certificates (CP12) explained

If you let a property containing gas appliances, pipework or flues, the Gas Safety (Installation and Use) Regulations 1998 require an annual safety check by a Gas Safe registered engineer. The document produced is the Landlord Gas Safety Record, still universally called a CP12 after the old certificate number.

It is a legal duty, it sits with the landlord (not the tenant, and not the agent unless contractually agreed), and it cannot be delegated away.

The rules in short

• A check on every gas appliance and flue in the property, every 12 months
• A copy to existing tenants within 28 days of the check
• A copy to new tenants before they move in
• Records kept for at least two years
• Gas pipework and installation maintained in a safe condition
• The engineer must be Gas Safe registered for the appliance types being checked

Appliances owned by the tenant are not the landlord's responsibility to check, but the flue serving them is.

What the engineer checks

For each appliance:

• That it is on a sound, stable, and correctly installed setting
• Gas tightness of the installation and correct operating pressure and heat input
• Combustion performance, via flue gas analysis where the appliance allows
• The flue: condition, route, support, termination, and clearance from windows and openings
• Adequate permanent ventilation for the appliance, unobstructed
• Operation of safety devices — flame supervision, overheat cut-offs, relief valves
• Flues in voids must be accessible via inspection hatches; without them the appliance may be classified At Risk

Anything unsafe is classified as At Risk or Immediately Dangerous under the Gas Industry Unsafe Situations Procedure. With your permission the appliance is turned off and labelled; if permission is refused, the engineer is obliged to report it to the Gas Emergency Service.

Renewing early costs you nothing

If the check is carried out in the last two months of the current record's validity, the new expiry date runs 12 months from the old expiry — not from the date of the check. So booking early never loses you time, and it's the simplest way to avoid an accidental lapse when a tenant won't answer the door.

Access problems

Landlords are expected to take reasonable steps to gain access, and to document them: written appointment requests, repeated attempts, recorded delivery letters, and reference to the tenancy agreement's access clause. Keep the paper trail. If you can evidence genuine repeated attempts, you have a defence; if you simply gave up, you don't.

Penalties for getting it wrong

Failure to hold a valid record is a criminal offence prosecuted by the HSE. Penalties range from substantial fines to imprisonment where a serious incident follows. Beyond that:

• Property insurance can be invalidated
• In England, a valid gas safety record is a precondition for serving a Section 21 notice
• Local authorities can take enforcement action against the property

CP12 vs a boiler service — they are not the same

A CP12 confirms an appliance is safe on the day. A service cleans and maintains it so it stays safe and efficient, and it's what the manufacturer's warranty requires. Many landlords book both together, which is the sensible approach: one visit, one appointment with the tenant, both duties covered.

HMOs and multiple properties

For HMOs and portfolios the practical difficulty is never the inspection, it's the diary. We hold renewal dates for landlord clients and contact tenants directly to arrange access, so certificates renew on schedule without you chasing.

Landlord gas safety checks in Lincolnshire

We carry out CP12 checks across Lincoln, Boston, Skegness, Louth, Sleaford, Grantham, Spalding and the surrounding area. Certificates are emailed the same day, tenants receive their copy, and we set an annual reminder so it never lapses. Landlord care plans combine the CP12, the annual service and breakdown cover into one monthly payment per property.