Every gas appliance and flue in a let property must be checked for safety every twelve months by a registered engineer. The record must reach existing tenants within 28 days and new tenants before they move in, and must be kept for two years.
The three duties
Under the Gas Safety (Installation and Use) Regulations 1998, a landlord must:
- Maintain gas pipework, appliances and flues in a safe condition. This is a continuing duty, not an annual one – it applies every day of the tenancy.
- Check every gas appliance and flue for safety at intervals of no more than twelve months, by a registered engineer.
- Record and issue. Give the record to existing tenants within 28 days of the check, and to any new tenant before they move in. Keep records for two years.
The duty sits with the landlord. It does not transfer to a managing agent unless that is expressly agreed, and even then the landlord remains responsible in law. It applies to appliances the landlord owns and to the flues and installation pipework serving the property.
The twelve-month rule, and the flexibility in it
The interval must not exceed twelve months. There is, however, a useful provision: a check carried out in the two months before the anniversary date can be treated as though it had been done on the anniversary itself, preserving the original date rather than letting it drift earlier each year.
Why that matters practically:
- You can book early around tenant availability without shortening your cycle.
- You can align multiple properties onto a common month without losing time.
- You have margin to deal with access problems without going out of date.
- You can build in time to rectify a defect before a tenancy starts.
If you are having the check done early, make sure the record reflects the anniversary date rather than the visit date, so your cycle stays stable. It is a small administrative point that saves several weeks a year over a portfolio.
What gets checked
Every gas appliance and flue in the property, plus the installation serving them:
- Appliance operation and that it is burning correctly, with combustion analysis where the appliance type allows.
- Flue integrity and terminal position – that combustion products are removed safely.
- Ventilation – present, adequate for the appliances, and unobstructed. Blocked-up airbricks are a recurring find.
- Safety devices operating correctly.
- Gas tightness of the installation and the operating pressure.
- Installation pipework, visually along its accessible route.
What it is not: a service. The safety check establishes whether the appliance is safe today; it does not include the manufacturer’s cleaning and maintenance, which the warranty requires. The landlord’s legal duty is the check; the warranty condition is the service. Most landlords should have both, and they are commonly done in one visit.
The classifications
| Code | Meaning | Consequence |
|---|---|---|
| ID – Immediately Dangerous | Risk of injury or death now | Appliance turned off and labelled with permission. Emergency provider notified if permission is refused |
| AR – At Risk | Defects that could become dangerous | Turned off with permission until rectified |
| NCS – Not to Current Standards | Does not meet today’s requirements but is not dangerous | Recorded and explained. Landlord decides |
| Pass | No defects found | Record issued |
An ID or AR classification means the appliance is turned off, and it may mean the property is not lettable in its current state. That is a strong argument for booking with enough margin to rectify something, rather than the day before a tenancy starts.
The access problem
The most common practical difficulty is not the engineer – it is getting into the property.
The regulations recognise that landlords cannot force entry, and expect them to take all reasonable steps to gain access. What matters is that those steps are documented.
- Tenancy agreements should require access for safety checks and inspections. If yours does not, add it at renewal.
- Write, and keep copies. Letters, emails and texts, dated, explaining why access is needed and offering appointments.
- Offer more than one appointment, including outside normal hours where you can.
- Record attended visits where nobody was in.
- Escalate in writing, explaining the legal position and the safety reason.
- Keep the whole file. It is the evidence that you took all reasonable steps, and it cannot be created retrospectively.
Some landlords attempt entry using a right of access clause. That is legally fraught and it risks harassment allegations. Documented persistence is the better route, and it is what the regulations actually expect.
Where a tenant refuses or repeatedly misses appointments, a landlord’s position rests entirely on having documented reasonable steps. Dated evidence of attempts is the whole defence, and the moment you need it is the moment it is too late to create it.
Related obligations often missed
- Carbon monoxide alarms are separately required in rented property in England – in any room used as living accommodation containing a fixed combustion appliance, with repair or replacement when a tenant reports a fault. This includes solid fuel and oil appliances, not just gas.
- Smoke alarms – one per storey, working at the start of each tenancy.
- Electrical installation condition reports every five years.
- Legionella risk assessment, as a duty holder.
- Oil-fired appliances have no statutory annual requirement, which is exactly why they get missed. An oil-fired let with no service history is a liability with insurers regardless.
For portfolios, getting these onto a single managed calendar is the change that makes the difference – see landlords and letting agents.
Several properties? Aligning them onto one renewal cycle makes the whole calendar manageable and the visits cheaper.
Questions we get asked about this
How often is a landlord gas safety check required?
Every twelve months. A check done within the two months before the anniversary can be dated to the anniversary, which keeps your cycle from creeping earlier each year.
Is a CP12 the same as a boiler service?
No. The check establishes safety and produces the legal record. A service is the manufacturer’s cleaning and maintenance, which the warranty requires. They are different pieces of work commonly done in one visit.
What if the tenant will not let us in?
Take and document reasonable steps – written requests, multiple appointment offers, attended visits. The regulations expect documented persistence rather than forced entry, and the file is your evidence.
Does it apply to holiday lets?
Yes. The duty applies to short-term lets and holiday accommodation as well as to assured shorthold tenancies.
What about the tenant’s own cooker?
The appliance is generally the tenant’s responsibility, but the landlord retains duties for the flue and installation pipework serving it. The engineer records the position.
What happens if I do not have one?
It is a criminal offence carrying an unlimited fine and, in serious cases, imprisonment. It will also invalidate most landlord insurance and can affect the validity of certain notices.
Regulations and standards referenced on this page
- The Gas Safety (Installation and Use) Regulations 1998 (SI 1998/2451) — UK Statute Law Database
You might also need
- Boiler fault codes: what they actually tell you
- Boiler Plus: what has to be fitted alongside a new boiler
- Boiler pressure: why it drops, why it climbs, and what to do
- Boiler warranties, and the things that quietly void them
- Combi, system or regular: choosing the right boiler type
- Flue positions, and why the location decides the boiler
Need this doing?
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