Gas Safety Certificate (CP12): What Landlords Must Have and How Long it Lasts

Summary

The Landlord Gas Safety Record (LGSR) — the document still known across the trade as the "CP12" after the old CORGI form number — is the single most important paperwork in the UK private rental sector for gas safety. It documents that every gas appliance owned by the landlord, every fixed gas pipework run and every flue serving a let property has been inspected and confirmed safe by a Gas Safe registered engineer.

For a heating engineer, issuing CP12s is one of the most steady revenue streams in the trade — annually recurring, legally compelled, and price-sensitive but not price-elastic (landlords cannot legally skip it). The work itself takes 30–60 minutes per property; the value is in the renewal pipeline, not the one-off ticket.

The most common landlord-facing mistakes — and where engineers get drawn into disputes — are: missing the 12-month deadline, mistaking a "boiler service" for a CP12 (different paperwork, different scope), failing to retain certificates for the required 2 years, and not providing a copy to new tenants within 28 days.

Key Facts

• Legal basis — Gas Safety (Installation and Use) Regulations 1998, regulation 36 (landlord duty).
• Frequency — every 12 months from the last completion date. The certificate is valid for exactly one year.
• Two-month early window — a check can be completed up to 2 months before the existing certificate expires and the new expiry date is calculated from the original expiry, not the new check date. This avoids the "creep" of dates each year.
• Retention period — landlord must keep certificates for 2 years minimum.
• Tenant copies — must be provided to existing tenants within 28 days of the check; to new tenants on or before the day they move in.
• CP12 origin — the form number from CORGI (Council for Registered Gas Installers), the predecessor scheme to Gas Safe. The number stuck even though the form name is now Landlord Gas Safety Record (LGSR).
• Gas Safe Register — the only recognised UK gas registration scheme since April 2009. CORGI registration ceased.
• Who can issue — only a Gas Safe registered engineer with the correct competence categories (typically CCN1 + CENWAT for domestic boilers, plus appliance-specific competences).
• Scope per appliance — flue test, gas tightness check, combustion analysis, working pressure, safety devices, ventilation, visible pipework condition.
• Not included by default — boiler service. A CP12 is a safety check; a service is a maintenance task. The two are often bundled but are technically separate jobs with separate scope.
• Penalties — unlimited fine and up to 6 months' imprisonment under HSWA 1974. HSE prosecutions for gas safety breaches have averaged £25,000+ in fines in recent years.
• HMO and serviced accommodation — same rules apply; no exemption for short-term lets.
• Tenant-owned appliances — not the landlord's responsibility for the appliance itself, but pipework and flue still are.
• Holiday lets / Airbnb (28-day rule) — short-term lets of less than 28 days are still classed as a "relevant tenancy" by HSE — CP12 required.

Quick Reference Table — When a Certificate is Required

Quick Reference Table — Inspection Scope

Detailed Guidance

What a CP12 inspection involves

For a typical 1-2 appliance property (combi boiler + gas hob):

CP12 INSPECTION SEQUENCE
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1. Confirm scope — all gas appliances, pipework, flue
2. Visual inspection of every appliance
3. Gas tightness test (let-by + tightness, 2-min stabilisation)
4. Working pressure at appliance
5. Combustion analysis on boilers + open-flued appliances
6. Flue flow test (spillage)
7. Ventilation check
8. Safety device function (FSD, flame failure, AAV)
9. Visual pipework check
10. CO alarm presence and test
11. Issue certificate (paper or electronic)
12. Email/post to landlord + agent

Typical time: 30 min for a 1-appliance flat, 45-60 min for a 3-appliance house. Allow more for older systems, decommissioned appliances or first-time visits.

What a CP12 is NOT

• Not a boiler service — a service includes burner clean, heat exchanger check, descaling and parts replacement. A CP12 is a safety check only. If a landlord asks for "service and certificate", quote both.
• Not a warranty document — gives no guarantee that an appliance will keep working. Just confirms safe at point of check.
• Not a flue gas analysis report — though analysis is done, the certificate isn't a substitute for a full FGA report on a newly commissioned boiler.
• Not a CO alarm install — though presence and function are checked, install of a missing alarm is separate work.

"At Risk" vs "Immediately Dangerous" classifications

Per the Gas Industry Unsafe Situations Procedure (GIUSP):

An ID classification means the certificate fails — the appliance is unsafe to use. Landlord must remedy before reletting.

Pricing CP12s

The price spread across the UK is wide:

Pricing structure:

• Per-property base — £45–£80 covering first appliance
• Per-additional appliance — £15–£25 each
• Multi-property contract — 15-25% discount for landlords with 10+ properties
• Out-of-hours surcharge — £30–£60 for evening / weekend access

For agents and portfolio landlords, the value is in the management contract — diary the renewal date, auto-message 8 weeks before expiry, secure access slot.

Tenant access and forced entry

Landlords cannot enter a rented property without notice (24-48 hours typically). If a tenant refuses access:

1. Landlord must show evidence of attempts to gain access (recorded delivery letters, dated emails, photo of cards through letterbox).
2. If the certificate cannot be renewed in time, landlord should write to the tenant explaining their legal obligation.
3. As a last resort, court order under section 11 of the Landlord and Tenant Act 1985.

HSE will accept "all reasonable steps" as a defence if access has genuinely been refused — but document everything.

Holiday lets and short-term rentals

HSE clarified in 2009 (and confirmed since) that any letting of less than 28 days, including Airbnb and serviced apartments, falls under the same gas safety regime. Owners often miss this. A CP12 is required annually and must be available to the property manager / cleaning team for inspection if requested.

Frequently Asked Questions

Is the CP12 the same as a boiler service?

No. A CP12 (LGSR) is a safety inspection required by law for landlords. A boiler service is preventive maintenance — recommended by every manufacturer but not legally required. They cover overlapping items but are not equivalent. Most engineers bundle both as "service and certificate" for £90–£160, with the CP12 portion being the safety-check element.

How long is a CP12 valid for?

Exactly 12 months from the date of inspection. There is a 2-month early renewal window that preserves the original expiry — if your certificate runs to 30 June and you renew on 15 May, the new certificate still runs to 30 June next year (not 15 May). This prevents the date "creeping" earlier each year.

Can the tenant request a copy?

Yes, the landlord must give tenants a copy of the LGSR within 28 days of the check. New tenants must have a copy on or before move-in day. Failure to provide a copy is itself a breach — and bars Section 21 (no-fault) eviction in England under the Deregulation Act 2015.

Does a landlord need a CP12 for an electric-only flat?

No. CP12 applies only to properties with fixed gas appliances or gas pipework owned by the landlord. An all-electric property requires no gas safety certificate — though an EICR (Electrical Installation Condition Report) is required every 5 years under the Electrical Safety Standards in the Private Rented Sector (England) Regulations 2020.

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

The landlord must demonstrate "all reasonable steps" to gain access — written requests, multiple appointment offers, recorded communications. If a tenant continues to refuse, document everything in writing; HSE will accept a documented refusal as a defence. As a last resort, a landlord can apply for a court order. Engineers should never break entry — the access dispute is between landlord and tenant.

Regulations & Standards

• Gas Safety (Installation and Use) Regulations 1998 — primary legislation. Regulation 36 sets landlord duties.

• Health and Safety at Work etc Act 1974 — overarching enforcement powers.

• Deregulation Act 2015 (England) — gives the LGSR / EPC requirement teeth for Section 21 eviction validity.

• Smoke and Carbon Monoxide Alarm (England) Regulations 2015 (amended 2022) — CO alarm rule, often linked to CP12 visits.

• Gas Industry Unsafe Situations Procedure (GIUSP) — the AR/ID classification standard, issued by IGEM.

• BS 6891:2015+A1:2019 — Installation and maintenance of low pressure gas pipework. Tightness test.

• BS 5440-1:2008 — Flueing for gas appliances of rated input not exceeding 70 kW net.

• BS 5440-2:2009 — Ventilation for gas appliances.

• BS 7967-2:2015 — Carbon monoxide in dwellings and other premises. CO measurement.

• Gas Safe Register — Landlord duties — primary industry resource

• HSE — Gas safety in rented properties — enforcement guidance

• GOV.UK — Smoke and CO Alarm Regulations explanatory booklet for landlords

• IGEM — Gas Industry Unsafe Situations Procedure (GIUSP) — industry classification standard

• Deregulation Act 2015 — Section 21 changes (legislation.gov.uk)

• electrical installation condition report — EICR for rented properties

• co alarm positioning — CO alarm rules, often checked at CP12

• competent person schemes list — Gas Safe and other CPS schemes

• landlord services quoting — how to quote portfolio work