Landlord Gas Safety Duties: The CP12 Gas Safety Record Explained

Quick Answer: Under the Gas Safety (Installation and Use) Regulations 1998, regulation 36, a landlord must have every gas appliance, flue and fitting they provide checked for safety every 12 months by a Gas Safe registered engineer, and must give the tenant a copy of the Gas Safety Record (commonly called a CP12) within 28 days of the check, or before a new tenant moves in. The record must be kept for 2 years. Only Gas Safe registered engineers may carry out the work; failure to comply is a criminal offence enforced by the HSE, with unlimited fines and up to 6 months' imprisonment.

Summary

The Landlord Gas Safety Record — almost universally called the "CP12" after the old CORGI form number — is the single most important compliance document for any rented property with gas. It is the landlord's legal proof that every gas appliance and flue they are responsible for has been checked and is safe to use. The duty sits squarely on the landlord (or their managing agent), not the tenant, and not the engineer.

For the tradesperson, the value of understanding these duties is twofold. First, gas safety checks for landlords are steady, repeatable annual work — a good engineer builds a book of landlord clients with renewal dates that recur every year. Second, landlords frequently misunderstand their obligations: they confuse a "gas safety check" with a "boiler service" (they are not the same), they think they can do checks themselves or use an unregistered handyman (they cannot), and they let records lapse. An engineer who knows the regulations precisely is a trusted adviser, not just a pair of hands.

This guide sets out exactly what regulation 36 requires, what is and isn't on the check, the differences between a safety check and a service, record-keeping and tenant-supply duties, and the common pitfalls that turn into HSE prosecutions. It applies to England, Wales and Scotland; Northern Ireland has equivalent provisions under separate but materially similar legislation.

Key Facts

Quick Reference Table

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Requirement Duty Time limit Legal source
Annual gas safety check Check each landlord-provided appliance & flue Every 12 months max GSIUR reg 36
Use a competent engineer Gas Safe registered, correct categories Each check GSIUR reg 3 & 36
Issue record to existing tenant Provide copy of CP12 Within 28 days GSIUR reg 36(6)
Issue record to new tenant Provide copy before occupation Before move-in GSIUR reg 36(6)
Retain record Keep copy of each record 2 years GSIUR reg 36(6)
Maintain installation Keep pipework/appliances/flues safe Ongoing GSIUR reg 36(3)
CO alarm (England) Fit in rooms with fixed combustion appliance At start of tenancy / from 1 Oct 2022 Smoke & CO Alarm (Amendment) Regs 2022
Early renewal window May check up to 2 months early, keep anniversary Up to 2 months before deadline GSIUR reg 36 (2018 amendment)

Detailed Guidance

What a Gas Safety Check Actually Involves

Regulation 26(9) of GSIUR sets out the minimum scope of a safety check on each appliance and flue. A competent Gas Safe engineer must check:

  1. Effectiveness of the flue — that products of combustion are being safely removed (flue flow and spillage tests)
  2. Supply of combustion air — that ventilation is adequate and not blocked
  3. Operating pressure or heat input — appliance is operating to manufacturer's data plate / standards
  4. Operation of safety devices — flame supervision, oxygen depletion sensors, etc., function correctly
  5. That the appliance is safe to use — overall condition, gas tightness of the installation

The engineer records each appliance, the results, any defects, and whether the appliance passed, and signs the record. Tenant-owned appliances are noted but the formal duty is on the landlord-provided ones.

CP12 vs a Boiler Service — They Are Not the Same

This is the most common landlord misunderstanding and worth being clear about with every client.

Gas Safety Check (CP12) Boiler Service
Legal requirement? Yes — annual, by law No legal requirement (but advised)
Purpose Confirm safe to use Maintain reliability/efficiency
Scope Safety of all gas appliances & flues Strip-down/clean of one appliance
Includes cleaning burners? No Yes
Duration Quicker, focused on safety Longer, more thorough

A safety check confirms the appliance is safe, not that it is maintained. Manufacturers' warranties usually require an annual service to remain valid, and an unserviced boiler can fail a future safety check. Many landlords sensibly book the service and the safety check together — but they are separate pieces of work and should be priced and recorded as such. Note that the underlying duty in reg 36(3) is to maintain appliances and flues in a safe condition, so a check alone does not discharge the maintenance duty if defects are found and ignored.

Issuing and Keeping the Record

The administrative duties trip up more landlords than the technical work:

The record can be given electronically (email/PDF) if the tenant agrees and can reasonably access it. As the engineer, leave the tenant a copy where practical and always provide the landlord/agent with a clear PDF promptly — this is part of the value you deliver and protects the landlord's compliance position.

The 12-Month Rule and the Early-Renewal Window

The check interval must not exceed 12 months. A 2018 amendment to GSIUR introduced welcome flexibility: a landlord can have the safety check carried out up to 2 months before the annual deadline while retaining the original anniversary date — the same logic as an MOT done early. This stops the renewal date drifting earlier each year and lets engineers schedule sensibly.

Worked example: if the last check was 15 August, the next deadline is 15 August the following year. Under the rule, a check done any time from 15 June to 15 August keeps 15 August as the next anniversary. A check done after 15 August (a lapse) resets the anniversary to the new date and means a period of non-compliance.

Carbon Monoxide and Smoke Alarms — Separate but Linked Duties

CO and smoke alarm rules are not part of GSIUR but are core to letting safety and frequently asked about alongside the CP12. In England, under the Smoke and Carbon Monoxide Alarm (England) Regulations 2015 as amended from 1 October 2022:

Scotland and Wales have their own, broadly stricter alarm regimes. CO alarms should meet BS EN 50291 and be sited per BS EN 50292 guidance. See the related carbon monoxide article for siting detail.

When an Appliance Is Unsafe — RIDDOR and Warning Notices

If you find an appliance that is Immediately Dangerous (ID) or At Risk (AR) under the Gas Industry Unsafe Situations Procedure (GIUSP), follow the procedure: with the customer's permission, disconnect/turn off and label, and issue a warning notice. Certain dangerous gas fittings must be reported to the HSE under RIDDOR (Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 2013), regulation 11, by the registered engineer. Make the landlord aware in writing — leaving a known-dangerous appliance in service is where the most serious prosecutions arise.

Frequently Asked Questions

Is a CP12 a legal document, or is the form optional?

The legal requirement under GSIUR reg 36 is for a record of the check containing prescribed information (appliances checked, defects, results, engineer's details and signature, dates). "CP12" is the traditional name of the form, originally from CORGI. You don't have to use any specific branded form, but the record must contain all the required information. In practice every Gas Safe engineer's software produces a compliant record, and "CP12" remains the universal shorthand.

Can a landlord do the gas safety check themselves?

No — never. Only a Gas Safe registered engineer holding the correct appliance categories may carry out the check and complete the record. This applies even if the landlord is a competent DIYer or works in another trade. Using an unregistered person is itself an offence, and any resulting record is worthless. Always check the engineer's Gas Safe ID card and the appliance categories on the back.

How often does the check need doing, and what counts as a lapse?

Every 12 months at most. The early-renewal rule lets a check be done up to 2 months before the deadline without moving the anniversary date. If the deadline passes without a valid check, the property is non-compliant from that moment — the landlord is in breach until a fresh check is completed, and the anniversary then resets to the new date.

Whose responsibility is the tenant's own gas cooker?

A gas appliance owned by the tenant is the tenant's responsibility to maintain. However, the installation pipework and any flue serving it remain the landlord's responsibility, and the landlord's duty to keep the overall installation safe still applies. The engineer should note tenant-owned appliances on the record and flag any dangerous situation regardless of ownership.

What are the penalties for not having a valid CP12?

Breaching GSIUR is a criminal offence enforced by the HSE. On summary conviction the penalty can be an unlimited fine and/or up to 6 months' imprisonment; more serious cases go to the Crown Court with potentially higher penalties. Beyond prosecution, a missing or out-of-date gas safety record can invalidate insurance and, in England, can prevent a landlord from validly serving a Section 21 eviction notice.

Regulations & Standards