Landlord gas safety certificates (CP12):the rules and the cost

What does the law require of landlords?

The duties are set out in regulation 36 of the Gas Safety (Installation and Use) Regulations 1998. The record the engineer produces is often called a CP12 or a landlord gas safety certificate. In summary, a landlord must:

• Have each gas appliance and flue they provide checked for safety within 12 months of installation, and at intervals of not more than 12 months after that.
• Use a Gas Safe registered engineer for the check and for maintenance of the gas equipment they provide.
• Give a copy of the record to each existing tenant within 28 days of the check.
• Give a copy to any new tenant before they move in. For a tenancy of 28 days or less, the record may be displayed prominently instead.
• Keep each record until two further checks have been done, or for 2 years from the last check if the appliance has been removed.

The duty covers the appliances and flues the landlord provides. HSE guidance says that where a tenant has their own gas appliance, the landlord is still responsible for parts of the installation and pipework serving it, but the tenant is responsible for checking the appliance itself, and its flue if that flue only serves their appliance.

When is the next check due?

Before April 2018, checking early pulled every future deadline forward. Regulation 36A, in force from 6 April 2018, fixed that: a check completed in the 2 months before the deadline is treated as if it were made on the deadline date. In HSE's words, you retain the original deadline date. It works much like an MOT.

A check before 15 January 2027 in that example would sit outside the window, and the new deadline would run 12 months from the day it was done. When you use the window, HSE says to keep records until two further checks have been carried out, so you can show the chain of deadlines.

What does the engineer check?

The law sets a minimum. Regulation 36(9) says the check must include, but is not limited to, the four examinations in regulation 26(9):

1. The effectiveness of any flue.
2. The supply of combustion air.
3. The appliance's operating pressure or heat input, or both where necessary.
4. Its operation, to make sure it functions safely.

Every permanent and portable gas appliance and flue you provide is in scope, which usually means the boiler plus any gas hob, cooker or fire. The written record must show the date, the address, your name and address (or your agent's), a description and location of each appliance and flue checked, any safety defect found and any remedial action taken, and the engineer's name, signature and Gas Safe registration number.

HSE accepts electronic records if they can be printed when needed and are secure from loss and interference. Tenants can receive them electronically if they agree, but can still ask for a paper copy.

How much does a landlord gas safety certificate cost?

The check tells you whether the appliances are safe on the day. It does not maintain them. Most boiler manufacturers also require a yearly service to keep their guarantee valid, which is why doing both in one visit is common. See what a boiler service includes.

What are the carbon monoxide and smoke alarm rules?

These sit in separate law, the Smoke and Carbon Monoxide Alarm (England) Regulations 2015 as amended in 2022, and apply to private and social landlords in England. From 1 October 2022, relevant landlords must:

• Fit at least one smoke alarm on each storey that has a room used as living accommodation.
• Fit a carbon monoxide alarm in any room used as living accommodation that contains a fixed combustion appliance, which includes a gas boiler but excludes gas cookers.
• Check each alarm is working on the day a new tenancy begins.
• Repair or replace an alarm once told it is faulty.

Local housing authorities enforce these rules and can fine a landlord up to £5,000 for failing to comply with a remedial notice. HSE recommends CO alarms that comply with EN 50291 and carry a recognised approval mark such as a Kitemark, and is clear that an alarm is not a replacement for the yearly check.

What happens if you miss a check, or the tenant will not let you in?

HSE is direct about it: a landlord without a valid check is putting lives at risk and breaking the law, and enforcement could result in a substantial fine and/or a custodial sentence.

Tenants sometimes do not answer the door. HSE inspectors look for at least three attempts to complete the check, with the approach suited to the situation. Leave notice with your contact details, explain in writing that the check is a legal requirement and is for the tenant's own safety, and keep a record of every attempt.

What if the check finds a problem?

An appliance classed as 'At Risk' or 'Immediately Dangerous' is labelled 'Danger Do Not Use', and HSE notes it is illegal to use an appliance suspected to be unsafe. It must be put right before the record can show it as safe. If an old boiler keeps failing, see repair or replace your boiler, and for the energy rating rules on rented homes, landlord EPC rules.

Common questions