The short answer
A tenant cannot fit fixed air conditioning without the landlord’s written permission, and the landlord may also need freeholder or planning consent. Because a fixed split involves drilling, a refrigerant circuit, electrical work and an outdoor unit, it alters the property and triggers F-gas, Part P and possibly planning rules. A plug-in portable unit needs no installation and is the practical option for most tenants. Always get permissions in writing before committing.
Renting complicates air conditioning because you do not own the building you want to alter. A fixed system is a permanent change with legal and structural implications, so consent is the first question, not the last. This guide sets out what tenants, landlords and leaseholders need to agree, and the realistic options for each. It is general information, not legal or tenancy advice; check your tenancy or lease and the relevant rules.
Rented property at a glance
- Tenant fitting fixed AC Needs landlord’s written consent
- Landlord May need freeholder / planning consent
- Refrigerant work F-Gas-certified engineer only
- Electrical Notifiable under Part P
- Flats Permitted development doesn’t apply
- Practical tenant option Plug-in portable unit
Why renting changes the answer
A fixed split air conditioning system is a permanent alteration: it means drilling through an external wall, mounting an outdoor unit, running a refrigerant circuit and adding an electrical circuit. None of that is something a tenant can do unilaterally, because it changes a property they do not own. Most tenancy agreements prohibit alterations without the landlord’s written consent, and fitting air conditioning without it can breach the tenancy and leave the tenant liable for reinstatement at the end of the term. The first step is therefore always to ask the landlord in writing, and to keep that permission on record.
Consents stack up
Even with the landlord’s agreement, the permissions can stack up before anything is fitted:
- Landlord’s consent — the tenant’s starting point, given in writing.
- Freeholder or superior landlord consent — often needed where the landlord is themselves a leaseholder, especially in flats.
- Planning permission — flats and maisonettes are outside permitted development, so an outdoor unit may need an application; conservation areas and listed buildings add further restrictions.
- Building control and F-gas — the electrical work is notifiable under Part P and the refrigerant work needs an F-Gas-certified engineer.
Options by situation
| You are… | Realistic option |
|---|---|
| Tenant in a house | Portable unit, or fixed AC only with landlord consent |
| Tenant in a flat | Portable unit; fixed AC needs landlord + freeholder + likely planning |
| Landlord | Can add fixed AC; check lease, planning, F-gas, Part P |
| Leaseholder | Check lease for alteration clauses and freeholder consent |
For most tenants, a plug-in portable unit is the pragmatic answer: it needs no drilling, no refrigerant work and no outdoor unit, so it sidesteps the consent stack entirely — you simply vent its exhaust hose through a window. The trade-off is lower efficiency and more noise inside the room. To compare it with a fixed system, read portable vs fixed air con.
For landlords considering air conditioning
A landlord can install fixed air conditioning as an improvement, but must still navigate the lease (if they are themselves a leaseholder), planning where it applies, the F-gas requirement to use a certified engineer, and the Part P notification for the electrical work. Air conditioning can add appeal and, where it doubles as a heat pump, efficient heating — but it is a capital cost and an ongoing maintenance and service responsibility that falls on the landlord. For the system’s service needs over its life, read air con servicing explained.
The sensible sequence
Whoever you are, the order is the same: confirm consents in writing, then engage an F-Gas-certified installer to survey, design a compliant outdoor position, and handle the Part P electrical notification. Reinstatement terms — what happens to the equipment and the wall when a tenancy ends — are worth agreeing up front so there is no dispute later. Treating air conditioning as a documented, consented project rather than a quiet weekend job protects the tenant, the landlord and the building alike. For the planning element, see do you need planning permission.
A few practical questions settle most disputes before they start. Who pays for the installation, and who owns the equipment if the tenant funded it? Is the system left in place at the end of the tenancy, or removed and the wall made good, and who bears that cost? Will the landlord take on the annual service, since a neglected system loses efficiency and can leak? Putting the answers in writing — ideally as a short agreement attached to the tenancy — means everyone knows where they stand. Air conditioning can be a genuine improvement to a rented home, but only when the consent, the certification and the end-of-tenancy terms are all agreed before the first hole is drilled.
Sort consents before fitting
Tenants: get written landlord permission first. Landlords: check the lease, planning and use an F-Gas-certified installer for a compliant, notified installation.
Frequently asked questions
Can a tenant install air conditioning?
Not without the landlord’s written consent. A fixed split is a permanent alteration involving drilling, refrigerant and electrical work, so most tenancies require permission first. A portable unit needs no consent.
Does a flat need extra permission for air con?
Usually yes. Permitted development does not apply to flats, so an outdoor unit may need planning permission, and freeholder consent is often required in addition to the landlord’s.
What is the easiest option for renters?
A plug-in portable unit, because it needs no drilling, refrigerant work or outdoor unit and vents through a window. It is less efficient and noisier indoors but avoids the consent stack.
What must a landlord consider before fitting AC?
The lease and any freeholder consent, planning permission where it applies, the F-gas requirement to use a certified engineer, Part P electrical notification, and the ongoing service responsibility.
Sources & further reading
- gov.uk — private renting: alterations and tenant responsibilities
- Planning Portal — outdoor units and permitted development (flats excluded)
- gov.uk — Building Regulations: Approved Document P (electrical safety)
- gov.uk — Fluorinated Greenhouse Gases Regulations 2015 (refrigerant work)
This guide is general information, not a site-specific survey or a substitute for a quote from an F-Gas-certified installer. Installation, servicing and refrigerant handling are legally restricted to F-Gas-certified engineers.