Practical guide
Managing the shared plumbing system
The shared plumbing system is one of the building components that generates the most complaints and disputes among owners, because a hidden leak in a riser pipe can damage several units at once and raise questions about who should pay for what. Managing it properly requires the property manager to do three things: know how to distinguish shared plumbing from private pipework, run scheduled maintenance that prevents failures rather than chasing them, and apply the cost allocation rules set out in the Italian Civil Code without improvising. This guide covers how to organize maintenance of shared risers, how to respond to a leak, how costs are split among owners, and how to handle an insurance claim, all with the goal of limiting damage and disputes.
What counts as shared plumbing
Article 1117 of the Italian Civil Code lists water and sewage systems, up to the branch point serving each privately owned unit, among the building's common parts, unless the property deed states otherwise. In practice, the vertical risers running through the building, the horizontal collectors, the main drainage pipes and any booster pump or water system control unit are shared; the sections branching inside a single apartment, together with fixtures and taps, belong exclusively to the individual owner.
This distinction is not merely theoretical: it determines who pays for the repair and who is liable for damage if a pipe bursts. A leak in a riser, even if it shows up inside an apartment, for example as water staining on a ceiling, is a shared-property matter if the broken section is the shared one; if instead the break is in the pipe feeding only one unit's sink, both the liability and the cost remain with that unit's owner.
Scheduled maintenance of shared risers
Preventive maintenance drastically reduces the risk of sudden failures, which are almost always more costly and more damaging than a planned intervention. Galvanized steel or cast iron risers, typical of older buildings, tend to corrode from the inside over time and should be inspected periodically, while newer plastic pipework has a longer service life but still needs checks at the joints.
A good maintenance plan includes periodic visual inspection of accessible sections in basements, stairwells and utility rooms checking for oxidation, dampness and signs of corrosion, checking water pressure and the correct operation of the booster pump where one is installed, cleaning and checking the inspection chambers of the shared sewage system, and scheduling replacement of the oldest sections before they reach the end of their service life rather than waiting for them to fail.
The assembly approves the maintenance plan and its costs with the ordinary majorities set out in Article 1136 of the Civil Code for routine administration acts; larger interventions, such as fully replacing a riser, may require a specific resolution together with the corresponding cost allocation.
What to do when a leak occurs: response and communication
When a leak is reported, the priority is to isolate the affected section quickly to limit the damage, using dedicated shut-off valves where the system allows it. The property manager must act promptly, being responsible for the custody of the common parts, contacting a plumber for diagnosis and, if necessary, ordering an urgent intervention even without waiting for the assembly, within the powers Article 1130 of the Civil Code grants for works needed to prevent harm.
It is important to document the situation promptly with photos and a written report, both for technical management and for any insurance claim, and to notify without delay the owners whose units have been damaged. Timely, transparent communication about the ongoing intervention, expected timelines and initial assessments significantly reduces the risk of later disputes over how the emergency was handled.
Allocating costs among owners
Costs for maintaining and repairing the shared plumbing system are split according to the general ownership shares, following the criterion set out in Article 1123 of the Civil Code, unless the building's bylaws set a specific allocation table for that system. If the building has multiple staircases or blocks and the plumbing system serves only part of the building, the cost must be charged only to the owners who benefit from it, not to the whole building: a common mistake is charging everyone for work that concerns only one riser or one staircase.
When a leak has also damaged private areas, such as water staining on walls or ceilings of an apartment, two items need to be kept separate: the repair of the shared part, which follows the general allocation shares, and compensation for the private damage suffered by the owner, which is normally covered by the building's comprehensive insurance policy if one is in place. Keeping these two components separate in the financial statement avoids confusion among owners and makes it easier to review the accounts at the assembly.
Handling the insurance claim
If the building has a comprehensive property insurance policy, the property manager must open the claim promptly, gathering photographic evidence, the plumber's report and the repair quotes requested by the insurer. Timely reporting matters because most policies set tight deadlines for notifying an event, and a delay can complicate recognition of the damage.
For buildings with digitally organized accounting and documentation, managing the insurance claim, tracking quotes and communicating updates to affected owners becomes much simpler: AmministraPro allows the claim documents to be archived, the repair costs to be linked to the financial statement, and a history of interventions on the system to be kept, which is also useful in case of future disputes or when handing over to a new property manager.
Frequently asked questions
Who pays for repairing a riser that serves only some apartments?
The cost should be split only among the owners who use that riser, applying the ownership shares relevant to that part of the building or the specific table set out in the bylaws, not the general shares of the whole building. This avoids charging a localized intervention to owners who get no benefit from it, consistent with the proportional criterion of Article 1123 of the Civil Code.
Can the property manager have an urgent leak repaired without calling an assembly meeting?
Yes. Article 1130 of the Civil Code gives the property manager the power to carry out conservation measures necessary to prevent harm to the common parts, so in the presence of a leak that risks worsening the damage, an urgent intervention can be ordered and reported to the assembly afterward, with the cost presented in the next financial statement.
How do you tell a fault on the shared part of the plumbing system from one on the private part?
The criterion is Article 1117 of the Civil Code: water and sewage systems are shared up to the branch point serving each privately owned unit. If the broken pipe supplies water to the whole building or part of it, it is shared; if it is the internal section feeding only one apartment's fixtures, it is private and the cost stays with that unit's owner.
Why is it worth keeping a digital history of interventions on the plumbing system?
A history makes it possible to assess the real age of the pipework, schedule replacements before they fail, and quickly reconstruct past events in case of a new leak or a dispute raised by an owner. It is also useful for anyone taking over as property manager, since it avoids starting from scratch in understanding the system. Management software such as AmministraPro allows technical reports, quotes and costs linked to each intervention to be archived in one place.
A water leak damages the apartment below: who compensates the owner?
If the damage stems from a fault in the shared part of the system, compensation is generally the building's responsibility, often covered by the comprehensive property insurance policy where one exists; if instead the cause is a defect or negligence traceable to another owner's private plumbing, liability and compensation fall on that owner. When the cause is unclear, it is advisable to have a technician establish the origin of the fault before determining who should compensate whom.
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