Air conditioning in a listed building in England needs listed building consent wherever the work would affect the building's character as a building of special architectural or historic interest, and that applies inside as well as outside. Doing it without consent is a criminal offence. Planning permission is a separate question.
You have the lease on a Georgian building off a London square, the top floor is unbearable from June onwards, and the quotes you have been sent talk about kilowatts and condensers but say nothing about consent. That gap is where listed building projects go wrong. The equipment is the easy part. The question is what the building will allow, and who has to agree.
At a glance
| Question | Answer |
|---|---|
| Which law applies? | The Planning (Listed Buildings and Conservation Areas) Act 1990 |
| What needs consent? | Works to alter or extend a listed building "in any manner which would affect its character as a building of special architectural or historic interest" |
| Does internal work count? | Yes. Unless the list entry says otherwise, listing covers the entire building, internal and external |
| Is planning permission enough? | No. Listed building consent is needed irrespective of whether planning permission is also required |
| Does the application cost anything? | There is no fee for a listed building consent application |
| What if you go ahead without it? | A criminal offence under section 9, with up to two years' imprisonment or a fine on conviction on indictment |
Sources: Planning (Listed Buildings and Conservation Areas) Act 1990, section 7 and GOV.UK planning practice guidance, Historic environment
What counts as "the listed building"
People tend to picture the front elevation when they hear "listed". The law takes a much wider view. Section 1 of the 1990 Act treats any object or structure fixed to the building as part of it, and the same goes for any object or structure within its curtilage that forms part of the land and has done since before 1 July 1948. The government's planning practice guidance puts it plainly: "For all grades of listed building, unless the list entry indicates otherwise, the listing status covers the entire building, internal and external, and may cover objects fixed to it, and also curtilage buildings or other structures."
That matters for air conditioning because almost nothing about an installation is confined to one spot. A ceiling cassette means opening a ceiling. A wall unit means fixings and a core hole. The pipes have to travel somewhere, the condensate has to drain somewhere, and the outdoor unit has to sit somewhere. Each of those can touch fabric the listing protects, including inside rooms that look plain.
The list entry itself is worth reading before anyone designs anything. The Act allows an entry to exclude particular objects, structures or features from protection, so the entry for your building can change the answer.
When listed building consent is needed
The test sits in section 7. No one may carry out works "for the demolition of a listed building or for its alteration or extension in any manner which would affect its character as a building of special architectural or historic interest" unless they are authorised. The planning practice guidance repeats the point and adds that consent is needed "irrespective of whether planning permission is also required".
Two practical consequences follow. First, internal works can need listed building consent even where they need no planning permission at all. The guidance gives internal works to listed buildings as an example of works that may not be "development" for planning purposes, but the listed building test is a different test. Second, the person who decides whether a change affects character is not the installer. If there is any doubt, the conversation with the council's conservation team has to happen before the work, not after it.
| Part of the installation | Why it can raise a consent question |
|---|---|
| Outdoor condensing unit on a wall, roof or in a yard | Fixed to the building or placed within its curtilage; visible changes to the exterior and roofscape |
| Holes through walls for pipework and cables | Alteration of historic fabric, internal and external |
| Ceiling cassettes or ducted units | Opening ceilings that may carry plasterwork, cornices or historic joists |
| Wall-mounted indoor units and trunking | Fixings into historic walls and visible change to the room's character |
| Condensate drainage | New pipe runs and connections that cross historic fabric |
| Electrical supply and controls | New cable routes, isolators and controllers on historic surfaces |
Sources: the "affect its character" test in section 7 and the fixed objects and curtilage rule in section 1(5) of the 1990 Act. Whether a particular item affects character is decided by the local planning authority, not by this table.
The offence, and why it is not a technicality
Section 9 of the Act makes it an offence to contravene section 7, and also to ignore a condition attached to a consent. The penalties are not trivial. On summary conviction the Act allows imprisonment for up to six months or a fine, or both, and on conviction on indictment up to two years or a fine, or both. When fixing the size of a fine, the court is directed to take into account any financial benefit the offender has gained or is likely to gain from the offence.
There is a narrow defence for works that were urgently necessary for safety, health or the preservation of the building, limited to the minimum measures immediately necessary and with written notice to the planning authority as soon as reasonably practicable. A hot office in July is not what that defence was written for.
The section 9 wording also catches anyone who causes the works to be carried out, not only the engineer holding the drill. For a tenant, a landlord and a contractor, that is a shared reason to get the paperwork right.
Listed building, conservation area or neither
A conservation area is a different regime, and a building can sit in one without being listed. Under section 69 of the 1990 Act, local planning authorities designate areas whose "character or appearance" it is desirable to preserve or enhance. When the authority exercises its planning functions there, section 72 requires "special attention" to be paid to that aim. Listed building consent does not apply to an unlisted building just because it is in a conservation area.
| Listed building | Conservation area (unlisted building) | Neither | |
|---|---|---|---|
| Consent regime | Listed building consent for works affecting character, plus planning permission where the works are development | Planning permission where needed, judged with special attention to the area's character or appearance | Planning permission where needed |
| Inside the building | Covered, unless the list entry says otherwise | Planning rules only | Planning rules only |
| Who decides | The local planning authority | The local planning authority | The local planning authority |
| Working without consent | Criminal offence under section 9 | Planning enforcement where permission was needed | Planning enforcement where permission was needed |
Sources: sections 69 and 72 of the 1990 Act, with the listed building rows from section 9 and the GOV.UK guidance above
The planning permission side of an outdoor unit, including size, siting and noise, is covered in our guide to planning permission for air conditioning. This post sticks to the listed building layer that sits on top of it.
What an application usually involves
The planning practice guidance says a Design and Access Statement is required with certain applications for listed building consent, and that applicants should explain the significance of the heritage asset and its setting and how that understanding shaped the proposal. It also says the level of detail "should be proportionate to the asset's importance". For an air conditioning scheme that usually means drawings showing where every unit, pipe, cable and drain goes, photographs of the affected areas, and a clear explanation of why that layout does least harm.
From an engineering point of view, the useful thing is to design with those questions already in mind. Some of the options a conservation officer may want to see considered:
- Outdoor units placed out of public view, for example in a rear yard or a roof valley, rather than on a principal elevation.
- Pipe and cable routes that reuse existing service voids, risers or redundant flues instead of new cuts through decorative work.
- Indoor units chosen to keep away from cornices, ceiling roses and panelling, even if that means a different unit type.
- Fixings and penetrations that can be removed later with minimal damage.
None of these is a guarantee of consent. They are the conversation worth having early, because redesigning a pipe route on paper costs a fraction of what it costs once the plaster is open. For hotels and restaurants in historic buildings, our posts on hotel air conditioning and restaurant air conditioning cover the system choices.
When to get help
If your building is listed, get the survey and the design done before you ask anyone for a price, so the scheme you take to the council is one that can actually be built. Be Cool has installed commercial air conditioning across London and the South East since 2004, with F-Gas certified engineers and more than 2,000 projects behind us. Our commercial air conditioning installation team can survey the building and draw up a layout for you and your heritage adviser to take forward.
Frequently asked questions
Do I need listed building consent for air conditioning?
If the work would affect the building's character as a building of special architectural or historic interest, yes. That test applies to internal and external work, and the local planning authority decides whether it is met.
Is it illegal to install air conditioning in a listed building without consent?
Carrying out works that need listed building consent without it is a criminal offence under section 9 of the Planning (Listed Buildings and Conservation Areas) Act 1990.
Does it cost anything to apply for listed building consent?
No. The government's planning practice guidance says there is no fee for submitting an application for listed building consent.
Do indoor units need consent if nothing changes outside?
They can. Listing covers the entire building, internal and external, unless the list entry says otherwise, so internal work that affects character needs consent too.
Is a conservation area the same as a listed building?
No. A conservation area is designated by the local planning authority to protect an area's character or appearance. Unlisted buildings in it are dealt with through planning rules, not listed building consent.
Start with the building, not the brochure
Listed buildings can be cooled. The projects that go well start with the list entry, a survey and a conversation with the council, and only then move to equipment. As of October 2026 this reflects the Act and the planning practice guidance for England; if your building is in Wales, check the position locally.
About the author: Ali Elm runs Be Cool Refrigeration & Air Conditioning, a family-run London firm that has been installing, servicing and repairing commercial refrigeration and air conditioning since 2004. His F-Gas certified team has delivered more than 2,000 projects across London and the South East.
Last updated: 19 October 2026
Written by
Ali Elm
Ali is the Head of Operations at Be Cool Refrigeration with over a decade of hands-on experience in HVAC and commercial refrigeration. He oversees every installation, repair, and maintenance project, making sure the work meets the highest standards. Ali holds full F-Gas certification and has worked across residential, commercial, and industrial refrigeration systems throughout London and the South East. When he is not on site, he writes these guides to help business owners and homeowners understand their cooling systems better.