Neighbour complaining about your air conditioning? What actually happens next

What a complaint actually triggers

Your neighbour contacts the council's environmental health team. They log it and usually ask the complainant to keep a diary of dates and times for two to four weeks. If the diary suggests a genuine problem, an officer visits — sometimes with a sound meter, often at night.

Only if the officer judges the noise a statutory nuisance under the Environmental Protection Act 1990 does anything formal follow, and the first step is an abatement notice giving you time to fix it.

What counts as a statutory nuisance

There's no single decibel number in the Act. Officers weigh loudness, time of day, duration, how often it happens and the character of the area. A constant low hum at 2am in a quiet cul-de-sac is treated far more seriously than the same unit running on a hot afternoon beside a main road.

A modern inverter unit installed to the permitted development limit of 42 dB(A) at 1m from the nearest habitable window is very rarely found to be a nuisance.

The fixes that resolve most complaints

• Switch quiet / night mode on as the default — typically drops the outdoor unit to around 38 dB(A)
• Add anti-vibration rubber mounts or a floor plinth — kills the structure-borne hum through the wall
• Reposition the condenser away from the neighbour's bedroom window
• Fit an acoustic barrier or louvred screen (never boxed in — it needs airflow)
• Set a schedule so it isn't running overnight unless it's genuinely needed
• Service the unit — worn fan bearings and loose brackets are a common cause of a sudden new noise

Talk to them before the council does

The single most effective step is knocking on the door first. Most complaints are about the perception of being ignored rather than the decibels. Offering to switch to night mode, or to move the unit, usually ends it there — and a resolved conversation costs nothing, while a contested abatement notice can cost thousands.

Could you be made to remove it?

Ignoring an abatement notice is a criminal offence and can carry a fine up to £5,000 for a domestic property, plus the council can carry out works itself and bill you. But outright removal of a correctly sited, modern domestic unit is very unusual — the remedies above almost always satisfy the officer first.

FAQ