The short version
Air conditioning is an alteration to the building, not an appliance you plug in. That means a tenant needs the landlord's written consent, and a leaseholder normally needs the freeholder's consent too — even if the outdoor unit sits on your own balcony. Neither of them can be forced to agree, so the whole game is making it easy to say yes: certified installer, no cost to them, quiet unit, sensible siting, and a clear answer on what happens at the end.
Five steps to a yes
1. Check what governs your property
Tenants: the alterations clause in your tenancy agreement. Leaseholders: the alterations and 'external walls' clauses in your lease. Owners of a house: usually only permitted development rules apply.
2. Get the spec before you ask
Landlords and agents say yes to specifics, not ideas. Send us the room and we'll give you the exact unit, its decibel rating, the proposed outdoor position and the price — free, before you write to anyone.
3. Send the written request
Use the template below. Ask for the reply in writing, and keep it with your tenancy or lease paperwork.
4. Offer the two end-of-tenancy options
Leave it behind, or remove and make good. Giving both options up front removes the objection most landlords actually have.
5. Book the install
We'll copy your landlord or managing agent into the commissioning certificate and send them as-fitted photos, so the paperwork trail is closed.
What actually gets a refusal
| Their worry | What to say |
|---|---|
| "It'll damage the wall" | One 65 mm core hole, sealed and sleeved. Offer to make good on removal. |
| "Neighbours will complain" | ~48 dB(A) — quieter than a fridge at 3 m. Send the siting plan. |
| "Who fixes it when it breaks?" | You do, in writing, for the length of the tenancy. |
| "Is the installer qualified?" | F-Gas certified, NAPIT registered, insured — certificates on request. |
| "What about planning?" | Most houses are permitted development. Flats and conservation areas aren't — check first. |
| "I don't want it left behind" | Offer removal and make-good at your cost as Option B. |
The letter templates
Copy, fill in the brackets, send by email so you have a dated record. Send us the room first and we'll give you the real unit, decibel rating and price to drop into the blanks.
Tenant → landlord or letting agent
For assured shorthold tenancies. Covers cost, insurance and end-of-tenancy options.
Subject: Request for permission to install air conditioning Dear [Landlord / Agent name], I am writing to request written permission to install a domestic air conditioning system at [property address]. Details of the proposed work: - One wall-mounted indoor unit in the [room], with a single outdoor condenser unit fixed to the [rear / side] elevation. - Installation by CoolAir Midlands, an F-Gas certified and NAPIT registered installer, fully insured. - All work carried out to manufacturer specification, with an F-Gas commissioning certificate provided to you on completion. - The outdoor unit is rated at approximately 48 dB(A) and will be sited away from neighbouring windows and boundaries. Cost and responsibility: - I will pay for the installation in full. There is no cost to you. - I will cover servicing and any repairs for the duration of my tenancy. - The system will improve the property's comfort in summer and provides efficient heating in winter, which may reduce heating costs. End of tenancy: - [Option A] I am happy for the system to remain as a fixture and become your property at no cost to you. - [Option B] I will remove the system at my own expense and make good all fixings and the core hole to a professional standard. Please confirm in writing whether you are happy for this work to proceed. I am glad to provide the installer's certification, insurance details and unit specification, and to arrange for them to speak with you directly. Kind regards, [Your name] [Phone] | [Email] [Date]
Leaseholder → freeholder or managing agent
For flats. Framed as a formal application for consent to alter, including the usual undertakings.
Subject: Application for consent to alter — air conditioning installation Dear [Freeholder / Managing agent name], I am the leaseholder of [flat address]. I am writing to apply for consent to install a domestic air conditioning system, in accordance with the alterations provisions of my lease. Proposed works: - One wall-mounted indoor unit within the demised premises. - One outdoor condenser unit fixed to [the external wall at the rear / the balcony floor on anti-vibration feet], with a single 65 mm core drilled penetration, sealed and made good. - Condensate discharged to [existing drain / soakaway], not to the external face of the building. Installer and compliance: - CoolAir Midlands, F-Gas certified and NAPIT registered, with £[x]m public liability insurance (certificate available on request). - Sound pressure approximately 48 dB(A) at 1 m, sited to avoid nuisance to neighbouring flats. - Electrical work certified to BS 7671 and notified as required. - An F-Gas commissioning certificate and as-fitted photographs will be provided to you on completion. Undertakings: - I will meet all reasonable costs, including your surveyor's or solicitor's fees for granting a licence to alter. - I will maintain and service the system annually at my own cost. - I will remain responsible for the unit and will remove it and make good if required at the end of my lease. Please confirm what form of consent you require and whether a licence to alter is needed. I am happy to supply drawings, the manufacturer's data sheet and the installer's certification. Kind regards, [Your name] [Flat address] [Phone] | [Email] [Date]
We'll back up your request
Send us the property and the room and we'll email you (or your landlord or agent directly) a pack containing our F-Gas certificate, NAPIT registration, public liability insurance, the unit data sheet with its noise rating, and photos of comparable installs. It's free, and it turns a "no" into a "fine, as long as it's done properly" more often than anything else.
FAQs
Related guides
General guidance only, not legal advice. Your tenancy agreement or lease takes precedence — read the alterations clause, and take independent advice if a licence to alter or a large fee is involved.