The CP12 Explained — What Landlords Actually Need, and What You Must Record

The landlord gas safety record — still universally called a CP12 — is the most reliably repeating job in gas work. Every rented property with a gas appliance needs one, every twelve months, forever. Which makes it either a dependable annuity or a diary you are constantly losing track of.

This covers what the record has to contain, the renewal rule most people get wrong, and how to stop the annual repeat quietly disappearing.

Who needs one

Any landlord letting a property with a gas appliance, flue or pipework. That includes:

• Standard residential lets
• Rooms in an HMO
• Holiday lets and short-term lets
• Housing association and council stock

It does not include owner-occupiers, though plenty of homeowners buy one voluntarily when selling — which is worth mentioning, because it is a job most engineers never think to offer.

What the record must contain

A landlord gas safety record is not just a pass or fail. It has to identify:

• The address of the property
• The name, registration number and signature of the Gas Safe registered engineer
• The date of the check
• A description and location of every appliance and flue tested
• Any defects found, and the action taken
• Confirmation of the safety checks carried out on each appliance — including gas tightness, standing and working pressure, burner pressure or gas rate, operation of safety devices, and adequacy of ventilation and flue performance

The most common weakness is the appliance list. "Boiler — kitchen" is thin. If a second appliance exists and was not recorded, the record does not cover the property properly.

The 28-day rule people get wrong

You can carry out the check up to two months before the expiry date and keep the original expiry date, so the annual cycle does not creep forward each year.

Do it earlier than that and the new expiry runs twelve months from the check date instead — meaning you have shortened the landlord's cycle and given away part of a year. Over a portfolio, that quietly costs the landlord money and costs you a visit.

Setting the reminder to fire around six to eight weeks before expiry gets you the slot without losing the date.

Defects and what happens next

If you find something unsafe, classify it properly and follow the Gas Industry Unsafe Situations Procedure. Turning an appliance off requires the customer's permission, and the warning notice needs signing.

Whatever the outcome, the landlord gets a copy of the record within 28 days of the check, and new tenants get one at the start of the tenancy. Keep copies for at least two years.

Making the annual repeat actually repeat

This is where most gas businesses leak money. The check is done, the certificate is issued, everyone is happy — and twelve months later nobody remembers, the landlord books someone else, and a customer you already had is gone.

Three things fix it:

1. Record the expiry date against the property, not the customer. Landlords change agents and phone numbers; properties do not move.
2. Set the reminder at the point of issue, not later. If it is not scheduled before you leave, it will not be scheduled.
3. Remind the landlord and yourself. A landlord with eight properties genuinely cannot track eight renewal dates, and the engineer who reminds them is the engineer who keeps the work.

Gaffer tracks certificate expiry against the property and can chase both sides automatically. The gas engineer certificates and forms include the landlord gas safety record along with the Benchmark commissioning checklist, warning notices and building regs notifications — completed on site, signed on the phone, sent before you leave.

The short version

• Record every appliance and flue, not just the boiler
• Check within two months of expiry to keep the original date
• Issue to the landlord within 28 days, and to new tenants at tenancy start
• Set next year's reminder before you leave the property, or it will not happen