Household utilities

Allocation of water consumption also based on the number of people

The condominium regulations apply in the absence of meters in the flats

by Matteo Rezzonico

20 August 2025

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Key points

If meters are only installed in some flats
The Decision
Compliance with the conventional allocation criterion
Jurisprudential precedents

3' min read

Article 146 letter f of the Environment Code (Legislative Decree 152/2006), which deals with water saving, provides that 'the regions, having consulted the Supervisory Authority on water resources and waste, in compliance with the principles of state legislation, shall adopt standards and measures aimed at rationalising consumption and eliminating waste and in particular to:...f) install meters for water consumption in each individual housing unit as well as differentiated meters for productive activities and the tertiary sector exercised in the urban context'.

Consequently, where there are subtraction meters for recording water consumption in each apartment/unit, the criterion to be adopted for the allocation of water expenses is deemed to be that dictated by the actual consumption recorded by the meters. And yet - where only one meter has been installed in one (or some) of the exclusive properties - the question arises as to the correct criterion to be adopted. All the more so if the contractual condominium regulation expressly provides for a different allocation criterion for water consumption, e.g. by number of persons.

If meters are only installed in some flats

The Court of Appeal of Milan in its judgment of 16 July 2025 number 2165 resolves the issue, deemingthe condominium regulation to prevail, (hence the criterion determined by negotiation), all the times when the subtraction meters are not installed in all the flats, but only in some of them.

The case stemmed from a shareholder's challenge to a number of assembly resolutions: he objected, in particular, to the erroneous apportionment of expenses relating to water consumption, purging and lift maintenance, and requested their annulment. With regard to the apportionment of water costs, according to the appellant - who had installed a meter to measure the water consumption in his living unit - the judicial authority should have ascertained, inter alia, the ineffectiveness of the contractual condominium regulations (which provided for the apportionment by number of persons occupying the flats), as well as the condominium owner's right, pursuant to Article 146(f) of Legislative Decree 152/2006, to have the actual consumption recognised, as resulting from the meter installed. Moreover - again according to the appellant - the condominium should have kept the consumption of the individual dwellings separate from that of the common parts.

The Decision

The Court of Monza upheld the appellant's argument, annulling on this point the resolutions that had adopted different allocation criteria. Hence the condominium's appeal, for which instead the court should have sanctioned the inapplicability to the case in point of the principle set forth in Article 146 of the Environmental Code, if only because of the failure to install subtraction meters in all the apartments/private property units. In the appellant's view, the apportionment criterion should have been that per person provided for in the regulation.

The Court of Appeal of Milan reformed the ruling of the Court of Monza, agreeing with the condominium. According to the Court, in fact, the Court wrongly held that the provisions of Article 146 of Legislative Decree 152/2006 - which, by means of a public provision, provided for the installation of water meters in each individual dwelling unit, including condominiums, make it unnecessary to obtain authorisation from the shareholders' meeting for the installation of such meters. Nor is it true that the installation of a single meter in a unit legitimises the alteration of the criterion for apportioning the costs of water, established by the condominium rules, without the unanimous consent of all the participants in the condominium (that is to say, the holders of real rights: ownership, usufruct, use, habitation).

Compliance with the conventional allocation key

Indeed - even though one might agree with the principle that in the presence of metering systems it would be unreasonable not to take account of actual water consumption - the installation of the meter in a single property unit is not sufficient to overcome the conventional apportionment criterion. All the more so because the installation of a single meter does not allow for an appropriate division of the consumption inherent in the common parts and, in any event, does not guarantee the proportionality of the division of the expense among all the owners provided for by Article 1123 of the Civil Code.

Jurisprudential precedents

The Court of Appeal of Milan in its judgment 2165 recalls two important and well-known precedents on the subject:

Cassazione 17119/2022 according to which 'the agreement contained in the condominium contractual regulation on the apportionment of the costs of the water bill is valid, since such an agreement can then be amended only by unanimous decision of all the owners, and only by the installation of a subtraction meter in an individual property unit (Cassazione 17557/2014)';
Cassazione 17557/2014 according to which, in the absence of abstraction meters and in the absence of a different contractual apportionment criterion, for the correct apportionment of expenses the apportionment by ownership thousandths must be applied, since the expense for water consumption can be traced back to a propter rem obligation, which also has regard to the potential use of the service.