What the job involves
A landlord gas safety certificate, usually called a CP12 or Landlord Gas Safety Record, is the annual check that a landlord in the UK must have carried out on the gas appliances and pipework in a rental property. It must be done by an engineer on the Gas Safe Register, and they should be qualified for the type of appliance in the property. Ask to see their Gas Safe ID card before they start.
The engineer visits the property and checks every gas appliance the landlord is responsible for. That usually means the boiler, a gas hob or cooker, and a gas fire if there is one. They also look at the gas pipework they can see and test it for tightness. For each appliance they check:
- that it is installed safely and is in a safe working condition
- that the flue or chimney removes fumes properly
- that there is adequate ventilation where the appliance needs it
- that safety devices work
- that the burner pressure or gas rate is correct, where it applies
At the end you get the certificate, which records what was checked, any defects found and any action taken. The landlord must give a copy to tenants and keep records. The rules on timing are specific, so check the current guidance for your situation.
A safety check is not a boiler service. The two overlap a little, but a service involves cleaning and detailed work on the boiler that the safety check does not. Some engineers offer both in one visit, which can save a second trip.
What affects the price
The work is fairly standard, so prices are usually modest compared with most trade jobs. The differences come from a handful of things:
- Number of appliances. Each boiler, hob, oven or fire needs its own checks. A flat with a combi boiler and a gas hob takes less time than a house with several gas appliances.
- Type and age of appliances. Older appliances can take longer to inspect, and some are harder to test. Appliances in awkward spots, such as a boiler in a loft or a tight cupboard, take more time.
- Access. If the engineer has to move stored items, lift floor hatches or work around furniture, the visit takes longer. Poor access to the pipework or flue has the same effect.
- Location. Travel time and local demand for engineers vary around the UK. Busy urban areas and rural areas with few engineers can both push prices up, for different reasons.
- Who is doing it. A sole trader, a local heating firm and a large letting agent or national company price differently. Agents sometimes add a management fee for arranging the visit.
- Bundling. Having a boiler service done at the same visit, or booking several properties with the same firm, can change the price per property.
- Timing. Short-notice bookings, evenings and weekends can cost more. Booking in good time usually costs less.
- Defects and follow-up. If the engineer finds a fault, the certificate cost does not usually cover the repair. Revisits for a failed check, replacement parts and remedial work are charged separately.
- Access arrangements with tenants. Missed appointments and return visits can add cost, particularly if the engineer charges for wasted journeys.
The prices on this page show what other homeowners and landlords locally actually paid, which is a better guide than a national average.
Ways to keep the cost down
- Book early. Do not leave it until the certificate is about to expire. You get more choice, and you avoid paying a premium for a rushed slot.
- Get more than one quote. Compare like for like: same number of appliances, same scope and the same paperwork.
- Bundle the work. If the boiler is due a service, ask for the service and the safety check together. Ask how the combined price compares with booking them separately.
- Use one engineer year to year. A regular engineer knows the property and the appliances, and will often keep the price steady. They can also warn you about parts that are ageing.
- Make access easy. Clear the area around the boiler and any other appliances. Tell tenants the date well in advance and make sure someone can let the engineer in.
- Avoid missed appointments. Agree a time with the tenant in writing. A wasted visit is a cost you can avoid.
- Fix known problems first. If you already know about a leaking pipe joint, a dodgy flue or a faulty appliance, deal with it separately rather than finding out during the check.
- Do not skip the check. A cheap quote is not worth much if the paperwork is not valid. A lapsed certificate can leave you with legal and insurance trouble that costs far more.
What should be included in a quote
Use this as a checklist when comparing quotes:
- [ ] Confirmation that the engineer is Gas Safe registered, with their registration number
- [ ] The number and type of appliances included in the price
- [ ] Whether the price covers the pipework tightness test and flue checks
- [ ] A copy of the completed certificate, and how it will be delivered (paper or digital)
- [ ] Whether a boiler service is included or priced separately
- [ ] What happens if a defect is found: how it is reported, and how repairs are quoted
- [ ] Any charge for a return visit if access fails
- [ ] Travel or call-out charges, and whether VAT applies
- [ ] Payment terms
- [ ] How reminders for next year's check are handled
Questions to ask a heating engineer
- Are you Gas Safe registered, and can I see your ID card?
- Does your registration cover all the appliances in this property?
- Which appliances will you check, and is anything excluded?
- Will you carry out a tightness test on the pipework?
- If something fails, what do you do on the day? Will you make it safe, and do you turn the appliance off?
- Do you carry common spares, or would a repair need a second visit?
- How soon after the visit will I receive the certificate?
- Can you send reminders when the next check is due?
- If I book a service with the check, do you offer any saving on the combined visit?
How long it takes and what to expect
For an average home with a boiler and a hob, the visit typically takes a short time, often well under a couple of hours. More appliances or difficult access will lengthen it. The engineer will need to get to each appliance, so tenants should be told in advance. Gas supply may be switched off briefly during testing.
The engineer inspects each appliance, runs it, checks the flue and ventilation, and tests the pipework. If everything passes, you receive the certificate, usually the same day or soon afterwards.
If there is a problem, the engineer may label an appliance as unsafe and turn it off. This is for everyone's protection, and it is not a sales tactic. The engineer should explain what is wrong and what needs to be done. You then arrange the repair and, depending on the fault, a recheck.
Signs a quote is too cheap or too expensive
Too cheap
- The engineer cannot give a Gas Safe number, or the number does not match their name and business on the register.
- The quote does not say how many appliances are covered.
- The price seems to rely on a quick look rather than proper testing.
- There is no mention of a certificate or paperwork.
- A very low headline price is followed by extras for things that should be part of the check.
Too expensive
- The price is much higher than others for the same number of appliances, with no clear reason.
- Large fees for admin, travel or arranging access are not explained.
- A service or repairs are bundled in without being asked for.
- You are pressured to approve extra work on the spot, without a written breakdown.
The best check is to compare your quote with the prices on this page and with two or three other quotes for the same scope. If one is far out of line, ask why before you decide.