What Is a CP12 Gas Safety Certificate? A Landlord's Guide

The legal requirement

Under the Gas Safety (Installation and Use) Regulations 1998, every landlord in the UK must have all gas appliances, flues and pipework in a rental property checked every 12 months by a Gas Safe registered engineer. The record of that check is commonly called a CP12, or Landlord Gas Safety Record.

A copy must be given to existing tenants within 28 days of the check, and to new tenants before they move in. Records must be kept for at least two years. Failure to comply can mean unlimited fines and, in serious cases, imprisonment — and it invalidates most landlord insurance policies.

What the inspection covers

The engineer checks every gas appliance in the property — boiler, fire, hob, cooker — along with the flues, ventilation and pipework. Specifically:

• Appliances are operating at the correct pressure and burning gas safely
• Flues are intact and carrying combustion products safely outside
• Ventilation is adequate for each appliance
• The gas pipework passes a tightness test
• Safety devices are functioning

Cost and timing

On the Fylde Coast, a CP12 for a typical rental property with a boiler and one or two other appliances usually costs between £60 and £90. Multi-property landlords can usually agree a better rate per property across a portfolio.

The inspection itself takes 45 minutes to an hour. A well-organised engineer will work around tenants and issue the certificate the same day.

One tip that saves money: the law allows the annual check to be done in months 10–12 of the current certificate while keeping the original expiry date. Booking early means you never have a compliance gap and never shorten your certificate cycle.

What happens if an appliance fails

If an appliance is found to be dangerous, the engineer will classify it as either 'At Risk' or 'Immediately Dangerous' and, with permission, disconnect it. The landlord must then repair or replace it before it can be used again. A good engineer will explain the fault clearly and quote for the remedial work on the spot — it is usually cheaper to fix issues found at inspection than to wait for a breakdown.

Common questions