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Landlords · 4 min read

Landlord gas safety certificate: what NI landlords need.

If you rent out a property with a gas appliance, you need an annual CP12 certificate by law. Here's what it covers, how an installer on the network handles it, and what happens if the boiler fails.

Engineer with clipboard checking a boiler
Published 4 Mar 20264 min read

The legal position in NI

Under the Gas Safety (Installation and Use) Regulations, any landlord renting out a property with gas appliances must:

  • Have every gas appliance and flue checked annually by a Gas Safe registered engineer.
  • Keep a record (the CP12 certificate) for at least 2 years.
  • Provide a copy to the tenant within 28 days of the check, and to any new tenant on move-in.

Non-compliance is a criminal offence. Penalties can include fines and imprisonment. More immediately, it invalidates your landlord insurance if a gas incident occurs.

What the certificate covers

  1. 01 Every gas appliance in the property is inspected for safety.
  2. 02 Tightness test on the gas installation, checks for leaks.
  3. 03 Combustion analysis on boilers and flue integrity checks.
  4. 04 Ventilation and flue routing verified for compliance.
  5. 05 Written CP12 certificate issued on the day.
  6. 06 Certificate emailed to both landlord and tenant (satisfies 28-day rule).
  7. 07 Copy lodged with the installer and available on request for 7 years.

What happens if the boiler fails the check

If the installer finds a safety issue, the installer classifies the appliance as one of:

  • At Risk (AR), a fault exists but the appliance is still usable in the short term. Fix required soon.
  • Immediately Dangerous (ID), the appliance must be turned off and not used. We'll disconnect it with your agreement, lodge the notice, and quote a repair.
  • Not to Current Standards (NCS), the appliance was legal when fitted but doesn't meet modern standards. No immediate action required.

In every case the installer agrees the remedial work with you before proceeding and reinspect afterwards at no extra charge.

Portfolio landlords

If you manage 5+ properties, the installer can route the annual renewal across a planned schedule, cheaper per certificate, less admin for you. Certificates emailed automatically to tenants. Ask about portfolio rates.

Book your CP12

From £90 per certificate across Greater Belfast.

Issued on the day. Emailed to you and the tenant. Same-week appointments across Belfast, Lisburn, Bangor and surrounds.

See CP12 service

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CP12 due?

Send the property addresses and we'll route the renewals. emergency request.

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