Do You Need Planning Permission for Air Conditioning in Doncaster?

ElectriFusion Solutions · 25 September 2026

Usually not. A reverse-cycle air conditioning unit on a house in Doncaster is normally permitted development, which means no planning application, as long as it meets a short list of conditions. The exceptions are units that only cool, listed buildings, some positions in conservation areas, and flats. This is how each rule works as of September 2026.

Why air conditioning counts as a heat pump

Permitted development for heat pumps sits in Class G of Part 14 of the General Permitted Development Order. Since the rules were amended on 29 May 2025, Class G covers an air source heat pump as long as it is “not solely used for the purpose of cooling”. A reverse-cycle air conditioning unit is an air-to-air heat pump that heats as well as cools, so it can use Class G; a cooling-only unit cannot, and needs a planning application.

HMRC takes a similar view for VAT: its guidance states that most air conditioning units are air source heat pumps, which is why fixed units installed in homes are zero-rated until 31 March 2027.

The conditions for a house

• Number of units: one on a house that is not detached, two on a detached house.
• Size: the outdoor compressor unit can be no more than 1.5 cubic metres.
• Roofs: never on a pitched roof, and on a flat roof at least 1 metre from the edge.
• Walls facing a road: outside a conservation area, a unit on a wall that fronts a highway cannot be above ground-floor level.
• Noise: the installation has to comply with the MCS planning standard, MCS 020 a), which sets a limit of 37.0 dB(A).

One rule that still appears in older guides no longer applies: the requirement to keep an air source heat pump at least 1 metre from the property boundary was removed on 29 May 2025, with immediate effect.

How the 37.0 dB(A) noise check works

The limit is not measured at the unit. It applies at each assessment position, which MCS 020 a) defines as a point 1 metre outside the centre of any door or window to a habitable room of a neighbouring property: a room used for living or sleeping rather than only for cooking, and not a bathroom, toilet, hallway, corridor, utility or laundry room. The calculation is done for every position that could be affected, because the closest window is not always the loudest one.

• Sound power: the unit's A-weighted sound power level comes from the manufacturer's data, and the figure for any low-noise mode cannot be used.
• Reflecting surfaces: every surface within 1 metre of the unit that extends a metre or more beyond its edge in two or more directions, the ground included, makes the result louder; a low wall on its own does not count. A unit with more than three such surfaces around it, such as in a small lightwell, cannot meet the standard.
• Distance: measured in a straight line from the centre of the unit to the assessment position; each doubling of distance takes about 6 dB off.
• Barriers: a solid barrier that completely hides the unit from the window can take off 10 dB, and one that partly hides it 5 dB; a lighter barrier counts for less.

If the result at every assessment position is 37.0 dB(A) or lower, the noise condition is met. On a semi-detached or terraced house, which is most of Doncaster, that usually comes down to choosing a wall away from the neighbour's windows or putting a solid fence between the unit and them.

Conservation areas and listed buildings in Doncaster

City of Doncaster Council has designated 46 conservation areas, including residential suburbs such as Bessacarr, which the council describes as almost completely residential. In a conservation area the unit cannot go on a wall or roof that fronts a highway, or anywhere nearer a highway than the house itself. On a corner plot, where roads bound two sides, that can rule out a side wall as well as the front.

The council's current Article 4 directions deal with changes of use to houses in multiple occupation and the demolition of particular buildings, not external alterations, so for most homes the national rules apply unchanged. Doncaster also has around 800 listed buildings. A listed building has no Class G rights: installing a heat pump needs planning permission, and listed building consent where the work affects its character.

Flats

Flats are not “dwellinghouses” in planning law, so they do not get a house's allowance. Class G allows one air source heat pump for a block of flats, with an outdoor unit of no more than 0.6 cubic metres, but that is one unit for the whole building, and for noise purposes the other flats in the block count as neighbouring properties. For an individual flat, the freeholder or management company usually has to agree before anything is fixed to the outside, whatever the planning position.

Businesses

Class G applies to houses and blocks of flats. Air conditioning on shops, offices and other commercial buildings falls under different rules, and is checked site by site.

If you do need permission

A cooling-only unit, a listed building, a position that fails the conservation-area test, or a unit that cannot meet the noise limit all mean an application to City of Doncaster Council before installation. Councils assessing heat pump applications focus on the same issues the permitted-development rules control: Sheffield City Council's guidance, for example, names noise and appearance as the key considerations.

Our air conditioning Doncaster page covers prices, the Daikin models we fit and running costs at October 2026 electricity prices.

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