Every rented property with a gas appliance needs an annual gas safety check by a Gas Safe registered engineer, with a certificate issued to tenants. We carry out landlord gas safety checks (commonly known as a CP12) across Farnham, Guildford, Godalming, Farnborough, Fleet and Camberley, for individual landlords, letting agents and managing agents running a portfolio.
The Gas Safety (Installation and Use) Regulations 1998 place a legal duty on landlords to have every gas appliance, flue and installation pipework in a rented property checked for safety at intervals of no more than 12 months, by a Gas Safe registered engineer. This applies to any property let under a tenancy where the landlord has arranged for a gas supply, gas appliance or associated pipework to be installed or used, with limited exceptions that don't apply to the great majority of standard residential lettings.
The certificate produced from this check is generally referred to as a CP12, after the number of the form it replaced, though the regulations themselves don't use that term. Getting this wrong is not a paperwork technicality — it is a legal obligation with enforcement consequences, and it is the single most important compliance item most landlords carry.
ComGas Services UK Ltd Gas Safe · OFTEC · REFCOM F-Gas · CHAS · Constructionline
What the annual check covers
A statutory duty with a defined scope, not a rough visual check.
The annual landlord gas safety check follows a defined set of inspections, tenant duties and safety classifications set out in law. Here is what is involved, from what gets checked through to what happens if an appliance fails.
What's Actually Checked
A landlord gas safety check is a defined set of inspections on every gas appliance and the associated installation, carried out and recorded by the attending engineer.
Every gas appliance checked for safe operation and correct combustion
Appliance ventilation checked as adequate and unobstructed
Flue performance checked to confirm safe removal of combustion products
Physical stability and safe installation of each appliance
Gas tightness testing of the installation to check for leaks
Every appliance is classified during the check using the Gas Industry Unsafe Situations Procedure (GIUSP), and any finding is explained on the spot, not left for you to interpret from the certificate alone.
Immediately Dangerous: disconnected on the spot with the occupier's agreement
At Risk: may continue in use only with informed consent, or is turned off without it
Not to Current Standards: recorded for information, no action required at the time
Any Immediately Dangerous or At Risk finding is followed up with a clear repair quote
Landlords are expected to take all reasonable steps to arrange the annual check. Where a tenant isn't cooperating with access, a clear record of the attempts made is what demonstrates that effort.
Dated letters or messages requesting access at reasonable notice
At least two or three documented attempts, ideally with a final warning letter
Evidence that references the legal duty and the safety risk of an unchecked appliance
Engineer attendance records supplied for any visit that couldn't go ahead
The 12-month cycle allows early renewal without losing your date.
You can have the check carried out up to two months before the current certificate expires without losing your original renewal date — the new certificate's 12-month cycle then runs from the original anniversary date, not from the earlier check date. This exists so landlords aren't penalised for booking ahead of the deadline, but it doesn't extend the interval beyond 12 months from the original date, and a check carried out earlier than the two-month window resets the anniversary to that earlier date instead.
A landlord gas safety check and a boiler service cover different things and are governed by different rules. The gas safety check is a statutory requirement covering every gas appliance in the property, exists specifically to protect tenants, and must result in a certificate issued to them. A boiler service is manufacturer-recommended maintenance focused on the boiler's own performance and warranty conditions. The two are frequently confused because they can be carried out on the same visit, but a service alone does not satisfy the landlord's legal duty, and a gas safety check alone is not the depth of manufacturer-specification maintenance a service provides.
Check can be carried out up to two months early without losing the existing renewal date
The new certificate's 12-month cycle runs from the original anniversary date
A check carried out earlier than the two-month window resets the anniversary to that date
A boiler service alone does not satisfy the landlord's legal duty to certify gas safety
Reviews from real ComGas customers, shown as submitted through Google.
Posted on Google
Ricky Matthews
5 October 2026
Trustindex verifies that the original source of the review is Google.
I'm the site Manager at St Paul's primary school and we have used ComGas for a whole refit of our water pipes. They was brilliant excellent friendly team never left a mess and the pipe work is so neat and tidy very professional work. We Also had an issue with our school Kitchen gas interlock system I called on Thursday morning they was there checking it over and parts ordered and fixed by Monday morning definitely recommend this company for any of your works especially in schools.
Posted on Google
steve brown
5 October 2026
Trustindex verifies that the original source of the review is Google.
Comgas fit our central heating system six years ago and made a fantastic job of it .They have serviced it regularly every year ever since .
Matt has done the last two services for us and he is very thorough, he rectified a couple of small issues with the rads and is always pleasant and informative. He advices us of what he’s done and what he thinks will be required on our next years service.
We are happy to continue with their services and have found all the guys to be reliable and trustworthy.
Posted on Google
Julia Walker
30 September 2026
Trustindex verifies that the original source of the review is Google.
Paul Pharo turned up on an emergency,within minutes he gave us so much reassurance to a burst hot water pipe isolated went and got new parts and had the penthouse back up with hot water with minimal damage..
can’t thank him enough and the company Comgas
Posted on Google
Ian Chevalier
30 September 2026
Trustindex verifies that the original source of the review is Google.
First time we've used this company and it won't be the last. Very professional and efficient in everything they do and Matt was excellent in his knowledge and efficiency when dealing with our gas and plumbing problems.
Posted on Google
Kerryann Wood
25 September 2026
Trustindex verifies that the original source of the review is Google.
Really happy with the service! Matt came out to carry out our boiler service and was friendly, professional and did a great job. The office team were also lovely and really helpful when arranging everything. Would definitely recommend and use them again. Thank you!
Posted on Google
Rob Haynes
14 September 2026
Trustindex verifies that the original source of the review is Google.
Great service and the work completed in good time and professional company
Posted on Google
Ian Melville
11 September 2026
Trustindex verifies that the original source of the review is Google.
Boiler service today engineer Matt on site, again great job very thorough clean and polite would recommend Comgas very professional outfit lovely staff. 👍🛠
Posted on Google
Bazmac
8 September 2026
Trustindex verifies that the original source of the review is Google.
We use Comgas for our gas and water and Matt does a monthly check on the systems.
Always a pleasure do deal with.
Chloe in their office is really helpful with all enquiries
Barry
Nower House
Posted on Google
Lynn Brooks
8 September 2026
Trustindex verifies that the original source of the review is Google.
Highly recommend. I think the engineers name was Matt, came to service my boiler, friendly and got on with the job quickly and efficiently.
Rated 5.0 out of 5 from 75 Google reviews.
"Really happy with the service! Matt came out to carry out our boiler service and was friendly, professional and did a great job."
Kerryann, Google review, September 2026
"First time we've used this company and it won't be the last. Very professional and efficient in everything they do…"
Ian, Google review, June 2026
"…ended up coming to my place of work and sorting an old heating system that hadn't worked for years in a car showroom & workshop. Great team of guys"
If a certificate has already lapsed or a tenant is not cooperating with access, contact us directly so we can prioritise attendance rather than waiting for a routine booking.
CP12 is the informal name still widely used for a landlord gas safety record — the certificate produced when a Gas Safe registered engineer completes the annual safety check required under the Gas Safety (Installation and Use) Regulations 1998. The name comes from an old form number; the regulations refer to it as the landlord's gas safety record.
How often does a landlord gas safety check need to be done?
At intervals of no more than 12 months. You can have the check carried out up to two months before the current certificate expires without losing your existing renewal date, which the new certificate will run from instead of the earlier check date.
What happens if I let a certificate lapse?
A lapsed certificate means you are letting a property without a valid gas safety record, which is a breach of your legal duty and a genuine enforcement risk, separate from the safety risk of an unchecked installation. Book the next check as soon as possible and keep a record of when it was arranged.
Do I need to give my tenant a copy of the certificate?
Yes. Existing tenants must receive a copy within 28 days of the check. New tenants must receive a copy of the current record before they move in. Both are separate duties from having the check carried out at all.
What if the tenant won't give access for the check?
Document every attempt to arrange access — dated requests, reasonable notice, and ideally a final letter referencing the legal duty. This record is what demonstrates you took all reasonable steps if the check runs late. We can supply attendance records for any visit that couldn't go ahead.
What happens if an appliance fails the check?
It's classified as Immediately Dangerous, At Risk, or Not to Current Standards. An Immediately Dangerous appliance is disconnected on the spot. An At Risk appliance may continue in use only with informed consent while repairs are arranged, or is turned off without it. Either way, you'll receive a clear explanation and a repair quote, not just a fail notice.
Is a gas safety check the same as a boiler service?
No. The gas safety check is a statutory requirement covering every gas appliance in the property, with a certificate that must go to the tenant. A boiler service is manufacturer-recommended maintenance on the boiler specifically. We can carry out both on the same visit where useful.
We use essential cookies to run this website. With your permission, we’ll also use Google Analytics and page-speed measurement to improve it, and show a Google map on our Contact page. You can change your choice at any time in ‘Cookie settings’. Cookie policy
