The neighbour complains about the air conditioning: handling neighbour nuisance in a rental property without taking sides

Tuesday morning, quarter past nine. A report comes in from the resident at number 14: the neighbour's new air conditioning unit hums all night long and she hasn't slept properly in a week. You pull up the file and see that permission for that unit was never requested. An hour later, the resident at number 16 calls you himself: he had the unit installed precisely because his attic bedroom was impossible to cool in summer, and he doesn't understand why the neighbour went straight to you instead of just knocking on his door.

Two tenants, two reasonable stories, and both expect you to solve it. This isn't a one-off. The Netherlands is increasingly covered in outdoor units, and every late summer with a few warm weeks brings a new wave of installations. According to the Veiligheidsmonitor 2025 van het CBS (the Dutch statistics office's 2025 Safety Monitor), 20 per cent of people in the Netherlands experience nuisance from neighbours and more than 3 in 10 experience noise nuisance in their neighbourhood; 1 in 10 experience this to a serious degree. And neighbour nuisance in a rental property almost always ends up on your desk, because you're the point of contact for both parties.

Neighbour nuisance in a rental property is never just one report

The trap is treating this as a single complaint from tenant B about tenant A. In reality, you're holding two files, and each deserves its own track.

The first file is the nuisance report itself: a tenant reporting that her enjoyment of her home is being affected. You register that report, confirm it and give it an expected turnaround time, exactly as you would with a repair request. Neighbour nuisance in a rental property feels urgent to the person reporting it, so silence on your part gets read as taking the other tenant's side.

The second file is the alteration to the rented property: there's an installation on the facade for which no permission was requested. That's a business matter between you and tenant A, and you deliberately keep it separate from the neighbour dispute. The moment you mix the two, every step you take towards tenant A looks, in the eyes of both parties, like a verdict on the conflict.

That separation is more than administrative tidiness. It defines your role: you're not the referee between two neighbours, you're the one handling a report and assessing a facade alteration. Lawyers at Achmea Rechtsbijstand also always advise, in cases of noise nuisance from an air conditioning unit or heat pump, that neighbours have a direct conversation first. You can facilitate that conversation without taking it over.

The 40 dB standard gives you an objective framework

What makes this case easier than the average neighbour dispute: for outdoor units, a hard, measurable standard exists. Under article 5.14 of the Besluit bouwwerken leefomgeving (the Dutch decree on buildings and the built environment), an outdoor installation for generating heat or cold, such as an air conditioning unit or heat pump, may cause no more than 40 dB at a home adjoining another home. That requirement also applies when the unit is installed at an existing home, not only in new-build situations.

That fundamentally changes the conversation. The question is no longer whether tenant B is 'too sensitive' or tenant A is 'inconsiderate', but whether the installation meets the standard. Have a sound measurement carried out, or ask tenant A to supply the sound power level from the installer's specifications. If the unit stays under the standard and the placement can otherwise be sorted out properly, you have a fair, sourced story to give tenant B. If the unit exceeds it, you have objective grounds to require tenant A to make changes: vibration dampers, a sound enclosure, relocation or, as a last resort, removal.

Either outcome gives you the same advantage: you don't need to have an opinion. The standard already has one.

Direct the communication, don't stand in the middle

The biggest mistake you can make now is becoming a postbox: tenant B complains to you, you pass it on to tenant A, and every reply comes back through your inbox. Within two weeks, you're the face of the conflict.

Work with a fixed sequence instead. Confirm in writing to both tenants what their report or situation is and which step follows when. Tell tenant B that the assessment against the noise standard is under way and what the outcome could be. Tell tenant A that the permission question still needs to be properly settled and under what conditions that can happen. And send a status update at every step, even when nothing has been decided yet. In nuisance files, the lack of visible progress is almost always a bigger source of escalation than the outcome itself.

At the same time, record every agreement and every point of contact in the file. If it still escalates towards a court or the Huurcommissie (the Dutch rent tribunal), your demonstrable, neutral handling of the process is your best protection.

Turn it into a playbook before next summer begins

This report will come back, just with different house numbers. If you set out a fixed approach now, with a permission procedure for outdoor units that includes the noise requirement and placement conditions, a split between the nuisance file and the alteration file, and standard status updates to both parties, you'll handle the next case in a fraction of the time. More importantly, both tenants will feel they were listened to, without you ever having to take sides.