The Gas Safety (Installation and Use) Regulations 1998 require every landlord to have every gas appliance, flue and pipework in a rented property checked every 12 months by a Gas Safe registered engineer. The engineer issues a Landlord Gas Safety Record — historically known as a CP12. You must give a copy to the tenant within 28 days of the check, and to any new tenant at the start of the tenancy.
A missed CP12 is a criminal offence. The HSE can prosecute for up to £6,000 per appliance. And the CP12 is one of the documents required for a valid Section 8 claim on most grounds — no CP12, no possession order.
Who can issue one
Only a Gas Safe registered engineer. Check the register at gassaferegister.co.uk before you book. Ask for the engineer's ID card on arrival — each engineer holds a different competency ticket (natural gas, LPG, boiler, cooker, combustion analysis). A boiler-ticketed engineer cannot sign off a gas cooker, and vice versa.
What is checked
- Gas appliances (boiler, hob, oven, fire, water heater) — operating pressure, heat input, combustion performance.
- Flues and chimneys — integrity, correct termination, no CO leak.
- Pipework — visible sections for leaks or corrosion.
- Emergency controls — accessible and operational.
- Ventilation — adequate air supply to each appliance.
The paperwork trail
- Engineer completes the check and issues the Landlord Gas Safety Record.
- You retain a copy for at least 2 years.
- You give a copy to the current tenant within 28 days.
- You give a copy to any new tenant at the start of their tenancy, before they move in.
- You record the check in your compliance log with date served and method.
Defects found
If an engineer classifies an appliance as 'At Risk' (AR) or 'Immediately Dangerous' (ID), they will disconnect it with your consent. You cannot refuse: a tenant in a property with a dangerous appliance has grounds to terminate. Get the repair booked the same day and a fresh record issued once fixed.
Typical cost
Expect £60–£120 for a boiler-only check, £80–£150 for a full house (boiler + hob + fire). Combined gas + EICR + EPC 'compliance pack' visits are commonly £200–£300 and save one booking. Keep receipts — the court and the deposit scheme will both want to see the invoice if you later claim a cleaning or repair deduction.
Our <a class='underline text-brand-700' href='/shop/landlord-annual-compliance-checklist'>Landlord Annual Compliance Checklist</a> tracks gas, EICR, EPC, deposit scheme renewal, Right-to-Rent re-checks and licence renewal dates in one sheet — so you never miss a 28-day window.