CP12 Gas Safety Certificate FAQ

By | 13th April 2017

A valid gas safety certificate is a legal requirement (1) in any rented or commercial property in the UK. The legislation supporting this has been around since 1998 and is widely publicised by the government. Despite this, many landlords are still failing their tenants and not providing gas safety checks on time for their homes (2).

Not having an inspection for the gas safety certificate could leave tenants at risk of illness or injury. Malfunctioning appliances could leak gas, risking an explosion, or could cause carbon monoxide (CO) to enter the living space, causing sickness and even death. As a landlord, you must ask yourself how much is a gas safety certificate worth to you?

Here’s what you need to know about the gas safety certificate in the UK, as well as answers to some of the most commonly asked questions.

What is a gas safety certificate?

A gas safety certificate is a document issued by a Gas Safe registered engineer, following an inspection of gas appliances in a property. It is proof that these appliances have been checked for safety and are considered safe for the residents to use.

Image showing an empty template for gas safety certificate

A sample cp12 or gas safety certificate

If you’re still unclear on what is a gas safety certificate, there is lots of information available on the HSE website.

What is a CP12?

A CP12 and a gas safety certificate are one and the same thing. CP12 refers to CORGI Proforma 12, from when CORGI was the national body for gas safety. Today it is run by the Gas Safe Register who took over from CORGI in 2009, but is often still referred to as a CP12.

Who needs a gas safety certificate?

Gas checks are required by anyone who is renting out a property or part of it to another person, either for money or for payment in kind, as well as anyone who owns a commercial property. For example:

  • Private landlords and social housing providers
  • Owners of hotels, guest houses and B&B’s
  • People with live in staff, lodgers or family members who pay rent
  • Student premises, halls of residence and those hosting students in the summer for money
  • ‘Hobby landlords’, Airbnb owners, caravan owners and those letting out holiday homes

There is a comprehensive article about who needs a gas safety check available here and advice from HSE available on their website.

How much is a gas safety certificate?

The gas safety check cost includes the engineer’s time at your property, and increases incrementally with every appliance requiring checks. If you have no gas appliances and it is only the main supply meter that needs to be tested, your gas safety check cost could be as low as £30 – £40 (3).

For most landlords and property owners, there will be at least one, if not more, appliances that need to be checked in addition to the meter. These are often charged at a per-appliance rate, so the more gas appliances to be checked, the higher the gas safety check cost.

More important than how much a gas safety certificate is, is that it is done annually and conducted by a registered Gas Safe engineer, keeping your investment and your tenants or guests safe and healthy.

What is checked during the CP12 inspection?

Your Gas Safe engineer will check all the appliances that YOU OWN in the property. Please note that they will not check things that your tenants have brought into the home, such as room heaters and standalone gas fires. However, these things should be checked, so it’s important to encourage your tenants to do this.

This usually includes gas fires, boilers, water heaters, cookers and any other gas appliances in the building. They will check for gas leaks, CO (carbon monoxide) leaks, they will check pressure, safety systems, flues, ventilation and mounting brackets. Everything they check is targeted at ensuring safety.

What happens if something fails a gas safety check?

If an appliance fails the gas safety check, the record will note the defect and your Gas Safe engineer will disconnect the device from the gas supply. You must repair or replace the appliance before a connection will be allowed again.

Who pays the gas safety check cost?

As the building owner and original landlord, you are responsible for the cost of the gas safety check. If you have a tenant who is subletting the property, you are still responsible, although you can ask the tenant to share the cost of the inspection.

Does my tenant have to give access for the safety check?

Ideally, you should have a clause in your contract which states tenants must allow access for maintenance and safety checks. You need to give the tenants at least 24 hours’ notice, but ideally will let them know at least a week before. Ensure you give this in writing, as a paper trail will help your case if there are any problems gaining access.

What if a tenant refuses access for the gas safety check?

You must take all reasonable steps to contact your tenant and to make arrangements for access. This should be documented and all records kept, so that you can demonstrate your attempts. Explain to your tenant the importance of having a CP12 gas safety certificate for the property, and how you are trying to keep them safe.

If they still refuse access, you should report the situation to appropriate bodies, including:

  • Your local Environmental Health Officer
  • The Health and Safety Executive
  • Your legal representative

You may not force entry to the property under any circumstances.

How long does a gas safety certificate last?

Your CP12 certificate will be valid for 12 months following the check. You need to arrange to have another check next year, so be sure to book it in good time. If possible, book your gas safety check in the summer months, when your Gas Safe engineer will be less busy.

There is no grace period, so if you’re unclear on how long a gas safety certificate lasts, be aware that from the very date of expiry, you will be liable if something goes wrong. The HSE is currently proposing some changes to the gas safety legislation (4) which may make it easier to maintain year round coverage, so do sign up to the HSE gas safety e-bulletin to keep up with any changes.

What will happen if I don’t get a CP12?

The penalties for not having a valid gas safety certificate can be extreme. Most cases incur a fine of up to £20,000, plus court costs, and the potential for up to six months in prison. If something happens, for instance someone is injured or killed, you could end up in court and subject to unlimited fines and criminal charges. The gas safety check cost is small compared to these risks, so think carefully before overlooking this important duty of care.


1. Gas Safety (Installation and Use) Regulations 1998. Legislation.gov.uk. [Online] 2017. http://www.legislation.gov.uk/uksi/1998/2451/contents/made.

2. Landlords failing tenants over gas safety checks. The Guardian. [Online] https://www.theguardian.com/money/2011/sep/19/landlords-tenants-gas-safety-checks.

3. Gas Safety Check Cost. Whatprice. [Online] 2017. http://www.whatprice.co.uk/prices/plumbing/gas-safety-check.html.

4. HSE Proposes Changes to Gas Safety Checks for Landlords. Landlord News. [Online] 2016. https://landlordnews.co.uk/changes-gas-safety-checks-landlords/.

5. Gas Safety (Installation and Use) Regulations 1998 Approved Code of Practice and guidance. HSE. [Online] 2017. http://www.hse.gov.uk/pubns/books/l56.htm.

6. One in five part-time landlords and holiday home owners flout gas safety rules and run the risk of ‘unlimited’ fines. This is Money. [Online] 2016. http://www.thisismoney.co.uk/money/buytolet/article-3592928/One-five-time-landlords-holiday-home-owners-flout-gas-safety-rules.html.

7. Penalties for non compliance with gas safety laws. PIMS.co.uk. [Online] http://www.pims.co.uk/penalties-non-compliance-gas-safety/.

8. Safety in the installation and use of gas systems and appliances. HSE.Gov.UK. [Online] 2017. http://www.hse.gov.uk/pubns/books/l56.htm.

9. The Smoke and Carbon Monoxide Alarm (England) Regulations 2015. Gov.UK. [Online] 2017. https://www.gov.uk/government/publications/smoke-and-carbon-monoxide-alarms-explanatory-booklet-for-landlords/the-smoke-and-carbon-monoxide-alarm-england-regulations-2015-qa-booklet-for-the-private-rented-sector-landlords-and-tenants.

10. A guide to landlords’ duties. HSE.gov.uk. [Online] 2017. http://www.hse.gov.uk/pubns/indg285.pdf.