Air Conditioning on the Balcony: Must the Owners' Association Approve a Split Unit?

With § 20 WEG, the legislator created a clear right to install an air-conditioning split unit – yet owners' associations often reject such applications out of hand. When you can enforce the installation and how I can represent you.

The heatwave summer of 2026 has made one thing clear to many flat owners: without air conditioning, a top-floor flat or one with a south-facing balcony becomes almost unbearable. So you put the request to the next owners’ meeting – and it is turned down, often without any real justification, simply because some of the co-owners dislike split units on the façade as a matter of principle. Does the association get to have the last word, or do you have an enforceable right?

In brief

Yes, as a general rule you have a right to be permitted to install an air-conditioning split unit, provided that no other owner is affected beyond the level that is unavoidable in an orderly shared living arrangement. This follows from the purpose of § 20 Abs. 3 WEG: a blanket refusal based on a mere dislike of the appearance is not enough – the association must genuinely examine and weigh up your request, not simply say “no”. If it refuses without justification, you can have the permission enforced through the courts.

How I can help you

• Checking whether your split-unit plans meet the requirements of § 20 WEG
• Drafting a resolution-ready application including the technical specifications (installation location, noise levels, façade penetration) that makes it easier for the association to give its consent
• Representing you at the owners’ meeting and during the passing of the resolution
• Following a refusal: bringing a claim for a substitute resolution against the association, so that the court itself grants the permission
• Monitoring the deadlines for the claim, so that your right does not lapse

Your statutory right: § 20 WEG

Since the 2020 reform of the German Condominium Act (WEG), a structural alteration is no longer a special case that the association may refuse at will. § 20 Abs. 3 WEG gives you a right to permission where all owners whose rights are affected by the measure beyond the level that is unavoidable in an orderly shared living arrangement have given their consent. Conversely, this means: where no one is unreasonably affected, the association must consent – there is no discretion to say “we simply don’t want this”.

The only statutory limit is drawn by § 20 Abs. 4 WEG: alterations that fundamentally reshape the residential complex, or that unfairly disadvantage an owner without their consent, may neither be resolved upon nor demanded. A single split unit on a balcony parapet or façade almost never reaches this threshold – the position would be different if, say, an entire external installation with several visible compressor units were to change the façade design of the complex as a whole.

What the association must actually weigh up

From the purpose of § 20 Abs. 3 WEG, the points to be examined can be summarised as follows – and these should also shape your own line of argument:

• Noise: the operating noise of a modern split unit will generally not stand in the way of the right, as long as the applicable immission guideline values are observed. A vague “this could be a nuisance”, without any concrete basis, is not enough for the association to justify a refusal.
• Appearance and façade: an intervention in the façade (a core drilling for the refrigerant line) is not an automatic ground for exclusion where the work is properly planned. Purely aesthetic reservations without solid substance are not enough to block the right.
• Location of the outdoor unit: the distance from neighbouring bedroom windows and visibility from the street play a role – here it pays to propose from the outset a location that is as unobtrusive and sound-insulated as possible.
• Future operating disturbances: should unreasonable interference actually arise after installation, the association can subsequently impose operating conditions – but this does not justify a refusal in advance where, at the time of the decision, there is no concrete indication of a disturbance.

The process: from application to court enforcement

1. Submit a substantiated application: don’t just put forward “air conditioning yes/no”, but a concrete concept – type of unit, sound power level as per the data sheet, the planned mounting location, a photo visualisation. This deprives the association of the ammunition for a blanket refusal.
2. Passing the resolution at the meeting: structural alterations are decided by a simple majority of the votes cast. If no majority is reached or the application is rejected, that is not yet the end of the matter – your substantive right under § 20 Abs. 3 WEG remains in place.
3. Claim for a substitute resolution under § 44 Abs. 1 S. 2 WEG: if the association fails to pass a positive resolution despite your right, you can apply to the competent court for it to pass the resolution itself and grant the permission. The claim is directed against the community of owners.
4. Observe the deadline: if your application is rejected by an express resolution (a negative resolution), that resolution must be challenged by an avoidance action under § 45 WEG within one month of the meeting – otherwise the refusal becomes final and binding. This one-month period applies only to the challenge of the negative resolution; the substantive right to permission under § 20 Abs. 3 WEG itself is not tied to it. If no resolution is passed at all, you can in principle bring the claim for a substitute resolution independently of this deadline. For reasons of legal certainty, however, you should still act promptly.

An example from practice

A top-floor owner asks the meeting to permit a split unit, as her flat heats up to over 30 degrees in summer. The outdoor unit is to be mounted on the rear, non-visible façade, several metres away from other people’s bedroom windows. One neighbour votes against, “because it doesn’t fit the ensemble” – without any further reasoning. The resolution fails to secure a majority. After a legal review it becomes clear: there is no concrete indication of noise or visual impairment going beyond the unavoidable level. By means of a claim for a substitute resolution, the permission is enforced through the courts, coupled with conditions on noise levels and condensate drainage.

Common mistakes

• Vague applications: anyone who merely applies for “I would like air conditioning”, without naming the unit, the location and the noise levels, hands the association ammunition for an unsubstantiated refusal.
• Missing the avoidance deadline for the negative resolution: if the application is rejected by an express resolution, this negative resolution must be challenged by an avoidance action within one month of the meeting, otherwise the refusal becomes final and binding – regardless of whether one still wanted to reach an “amicable settlement”. This deadline concerns the challenge of the negative resolution; the substantive right to permission itself is not tied to it, but should nonetheless be pursued in good time.
• Installing on your own initiative without permission: anyone who mounts the unit without a resolution risks a claim by the association for its removal – even where a substantive right to permission would have existed.
• Inadequate technical preparation: without a data sheet on the sound power level and without a proposal for the mounting location, it is difficult to prove in court that no unreasonable impairment is threatened.

Frequently asked questions

Can the association simply reject the air conditioning without giving reasons?

No. Since the 2020 WEG reform, the purpose of § 20 Abs. 3 WEG requires a concrete weighing of interests in each individual case. A blanket refusal without solid grounds will, as a rule, not withstand judicial review.

Do I have to bear the installation costs on my own?

Yes, in principle the applicant owner bears the costs of installing, operating and maintaining the split unit themselves, since this is a structural alteration made in their favour. In return, the association may impose conditions on how the work is carried out.

What happens if a neighbour later complains about the operation?

If unreasonable disturbances actually arise after installation – for example noise above the permissible values – the association can subsequently impose operating conditions or, in extreme cases, demand removal. That is not, however, a ground for refusing the permission out of hand in advance, as long as there is no concrete indication of a disturbance.

Does this right also apply to rented flats?

The right described here under § 20 WEG concerns the relationship between flat owners within the owners’ association. Tenants additionally need their landlord’s consent, and the landlord in turn – if they are themselves a flat owner – must take the route through the association described above.

How long does a claim for a substitute resolution take?

The duration depends on the competent court and on the complexity of the individual case, in particular on whether an expert opinion on noise levels has to be obtained. I will give you a realistic assessment of the likely duration in your case at our initial consultation.

Your next step

A rejected application at the owners’ meeting is not the last word – the legislator has deliberately placed an enforceable right in your hands with § 20 Abs. 3 WEG. Before you take matters into your own hands or give up in resignation, have your case assessed: I will evaluate the prospects of success with you, prepare a resolution-ready application, or initiate the claim for a substitute resolution before the deadline expires. You will find further topics relating to property and neighbourly relations on my topic page Real Estate Law. Contact me for an initial consultation – I will clarify the costs of it transparently with you, depending on your legal expenses insurance or the RVG.

This article provides general information and is no substitute for legal advice in an individual case. Last updated: 2026-07-27.

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