Commercial landlord air conditioning
By Airva Editorial Team · Checked against published UK guidance · Updated
Landlords tend to approach air conditioning as a letting decision — does the unit show better with cooling, and does it justify the rent. That part is easy. The part that catches people out is that the statutory duties attached to the equipment do not automatically transfer to whoever occupies the space. They follow the agreement, and if the agreement is silent, they may well stay with you. A landlord who installs a system, lets the unit, and assumes the tenant now owns the compliance can find several years later that nobody has been doing the leak checks, nobody has commissioned a TM44 inspection, and the records that should exist do not.
The duties follow the agreement, not the occupier
Government guidance on F-gas is unusually direct about this. Responsibility for having stationary air-conditioning equipment checked for leaks sits with the party that uses it — and it adds that if you rent out equipment, you may be responsible for the leak checks rather than the end user, depending on the rental agreement [1]. Responsibility for preventing leaks is shared between the users of the equipment and the service technicians who install, maintain or dispose of it [1].
Read that carefully, because it is the opposite of the assumption most landlords make. The default is not "the tenant is in occupation, so the tenant is responsible". The default is that it depends on what you wrote down. A landlord who retains the plant, or who lets a unit with air conditioning under a lease that says nothing about it, has not disposed of the obligation by handing over the keys.
This is a lease drafting question and it is worth taking proper advice on it. What we can tell you is which duties need allocating, so nothing gets missed when the drafting happens.
Who usually carries what
| Duty | Attaches to | The landlord's practical position |
|---|---|---|
| F-gas leak checks | The party using the equipment; may sit with the owner depending on the rental agreement [1] | Allocate explicitly. Silence in the lease does not move the duty to the tenant. |
| F-gas records (5 years) | Whoever is responsible for the checks [2] | Records outlive most tenancies. Retaining them centrally protects the asset at sale or refinancing. |
| TM44 inspection above 12kW | The person with control of the system [3] | In a multi-let building with retained plant, this is usually you — and the threshold aggregates. |
| Routine servicing | As drafted | Often tenant, but standardising it across a portfolio buys better rates and consistent records. |
| Replacement at end of life | As drafted | The most commonly omitted clause and the most expensive one to argue about. |
| MEES / EPC letting standard | The landlord [4] | A letting restriction, not a repairing obligation. It cannot be passed to a tenant. |
| Workplace temperature in retained common parts | The employer in that space [5] | Applies to your own staff in managed buildings. |
The leak-check threshold is lower than landlords expect
F-gas leak checks are widely assumed to be a supermarket-and-cold-store problem. The thresholds say otherwise.
Checks fall due at least every 12 months once equipment contains 5 tonnes of CO₂ equivalent or more; at least every 6 months from 50 tonnes; and every 3 months at 500 tonnes and above, where automatic leak detection also becomes mandatory [1]. Installing automatic leak detection doubles the permitted interval [1].
The number that matters is the conversion. For R-410A — still the refrigerant in a very large number of installed commercial systems — 5 tonnes of CO₂ equivalent is 2.4kg of refrigerant [1]. That is not a large charge. A multi-zone system serving a few floors of a let building will hold considerably more than that, and so will many single-unit installations of any size. The 50-tonne, six-monthly threshold arrives at 24kg [1].
There is one relief worth knowing: hermetically sealed systems have no maximum period between checks unless they contain the equivalent of 10 tonnes of CO₂ [1]. Most split and VRF systems in commercial buildings are not hermetically sealed in the sense that exemption means.
Failing to have the right leak checks in place, or failing to fix leaks, is a breach that can attract a civil penalty [1]. Records must be kept for five years [2]. Our TM44 and F-gas guide works through the bands in detail.
TM44 and the aggregation trap
Systems with an effective rated output above 12kW must be inspected by an accredited energy assessor at intervals not exceeding five years [3].
The trap is that the threshold is the combined effective rated output of the units serving a building under one person's control — not the rating of any single unit. In a multi-let building where the landlord has retained the plant, that aggregation runs across the whole building and clears 12kW without difficulty. Four modest cassettes in a small retail parade, all landlord-owned, count together even though no individual unit comes close.
Where each tenant has installed and owns its own system, the aggregation position is different. This is another reason to know precisely which equipment you own and which you do not — an asset register is the unglamorous document that answers both the TM44 and the F-gas question in one place.
MEES: a letting restriction you cannot delegate
Minimum Energy Efficiency Standard is separate from everything above, and it behaves differently: it restricts your ability to let, rather than imposing a maintenance duty. For non-domestic property, the F and G restriction was extended to existing tenancies from 1 April 2023 [4].
Landlords sometimes assume that installing air conditioning will help an EPC. It generally will not — cooling is a load, and adding it to a building can move the rating the wrong way. Our MEES and air conditioning guide explains what the assessment actually models and where the improvement budget is better spent. The short version for a portfolio: fix the fabric and the heating, and treat cooling as a lettability and comfort decision rather than an EPC strategy.
Specifying across a portfolio
Once the compliance position is settled, portfolio specification rewards priorities that differ from a single owner-occupier's:
Standardise the equipment. One manufacturer across a portfolio means one spares inventory, one set of engineer familiarity, and one service contract with real negotiating weight behind it. The aesthetic argument that dominates domestic choice barely registers here.
Prefer serviceable over cheapest. Parts availability over a fifteen-year holding period is worth more than a discount at installation. Our guide to the best air conditioning brand for rental property works through that trade-off.
Design the plant position for access, not just for planning. A condenser that needs a scaffold for every service visit converts a routine maintenance line into a capital-scale one, repeated annually for the life of the system.
Keep the paperwork in one place. Commissioning certificates, refrigerant charge in kg and tCO₂e, F-gas check dates, TM44 dates and assessor reports. This is what a purchaser's surveyor will ask for, and its absence is a price chip.
Zone for how units actually let. A building specified as one open floor and later subdivided will need re-zoning at the worst possible moment. Where subdivision is plausible, a multi-zone VRF design with independent branch control anticipates it.
For an ageing installation, a replacement is often the cleaner answer than progressive repair — it resets the refrigerant position, improves the efficiency the tenant pays for, and starts a fresh maintenance record.
What a landlord installation costs
Landlord projects are priced from a survey because unit count, subdivision, existing plant condition and access drive the cost more than floor area does. As planning figures drawn from our commercial cost guide:
- Ceiling cassettes in a fitted-out unit: typically £2,500–£4,500 per cassette installed.
- A multi-zone VRF system serving several units or floors from shared plant: commonly £8,000–£20,000 depending on zone count and plant siting.
- Ongoing: planned servicing, F-gas leak checks at the applicable interval, and a TM44 inspection at least every five years above 12kW. Budget these as a recurring line, not an occasional one.
Frequently asked questions
Is the landlord or the tenant responsible for air conditioning in a commercial lease? It depends on the agreement. For F-gas leak checks, government guidance states that where you rent out equipment you may be responsible rather than the end user, depending on the rental agreement [1]. Allocate it explicitly in the lease and take legal advice on the drafting.
Does the tenant taking occupation transfer the F-gas duty? Not automatically. Responsibility sits with the party using the equipment and is shared with service technicians [1], and the rental agreement can determine where it lands. Silence is not a transfer.
How much refrigerant triggers annual leak checks? 5 tonnes of CO₂ equivalent — which for R-410A is 2.4kg of refrigerant [1]. That is a smaller charge than most landlords assume.
Who arranges the TM44 inspection in a multi-let building? The person with control of the system. Where the landlord retains the plant, the 12kW threshold aggregates across the units serving the building under that control [3], so a landlord-owned installation usually falls in scope.
Will installing air conditioning improve the EPC? Generally not. Cooling is an energy load. MEES compliance is better pursued through fabric and heating measures — see our MEES guide.
How long must F-gas records be kept? Five years [2]. Retain them centrally rather than leaving them with successive tenants; they are asset documents.
Can a system be installed with tenants in occupation? Yes, and it is routine. It needs phasing agreed with each occupier, out-of-hours slots for noisy work, and access rights that the lease actually permits — check that before programming.
Specifying for a building you do not occupy
Tell us about the premises or the portfolio — unit count, existing plant, and how the space is let — and we will match you with one vetted, commercially capable installer. One enquiry goes to one installer, and your details stay private until they accept: start a business enquiry.