Sewer and Drain Cleaning: Who Pays in a Condominium

Cleaning sewers, drain pits and septic tanks is a periodic operation that keeps the wastewater disposal system efficient. In a condominium the cost falls on the owners, but the allocation criterion is not single: it depends on which portion of the system is involved. The common sewer collector, which gathers the discharges of the whole building, follows ownership thousandths (millesimi); a vertical waste stack serving only some units falls on the owners who use it. Telling the two cases apart avoids wrong charges.

Sewers are common parts

Article 1117 of the Italian Civil Code includes among common parts the sewers and drainage channels intended for collective use, up to the connection point with the public network. It follows that maintenance, periodic cleaning and the emptying of the common collector are the condominium's responsibility. These fall within ordinary conservation expenses when they are scheduled operations or the clearing of blockages affecting the shared network, whereas replacing the piping is extraordinary in nature.

Common collector: allocation by thousandths

When the work concerns the part of the sewer serving the entire building indistinctly, such as the buried horizontal collector, common inspection pits or the condominium septic tank, the first paragraph of Article 1123 applies: the expense is split in proportion to the value of the individual properties, that is by general thousandths. All discharges flow into that network, so the benefit is considered common.

Vertical waste stacks: only those who use them

The case of vertical waste stacks that collect the wastewater of a single line of stacked apartments is different. Since they serve only that group of units, the cost of cleaning or unblocking them falls exclusively on the owners concerned, under the third paragraph of Article 1123, which places the cost on the group that draws a benefit from the common part. Someone connected to a different stack need not contribute to unblocking that one.

Blockage from improper use

If the blockage is caused by improper use by a single owner, for example discharging unsuitable materials into the network, the cost of the intervention can be charged to whoever caused the damage, based on the liability principle. In these cases it is useful to document the cause with the cleaning company's report, because an individual charge requires reasonable proof of the link between the conduct and the blockage. Without proof, the expense follows the ordinary criterion of the common part involved.

How to identify the part involved

• Horizontal collector and common pits: allocation by ownership thousandths, Article 1123 paragraph 1.
• Vertical waste stack serving a few units: charged to the group served, Article 1123 paragraph 3.
• Condominium septic or Imhoff tank: common part, allocation by thousandths.
• Blockage due to documented improper use: charged to the responsible party.
• Rebuilding or replacing the piping: extraordinary expense, with owners' meeting resolution.

Ordinary nature and resolution

Periodic cleaning and unblocking generally fall within ordinary expenses that the manager can arrange as part of their duty to preserve the common parts, under Article 1130 of the Italian Civil Code. Rebuilding the sewer network or installing new pits are instead extraordinary maintenance works that must go through the owners' meeting with the required majority. Scheduling periodic operations, rather than acting only in an emergency, reduces costs and prevents flooding damage.

Keeping track of operations and criteria

The practical difficulty is remembering which stack or group each operation belongs to and applying the correct criterion year after year. Management software lets you assign the expense to the common part served and generate installments only for the owners concerned, avoiding disputes. With AmministraPro you set up allocation tables dedicated to the different portions of the drainage network and produce a transparent report: the allocation features are described on the /funzioni page and the plans on the /prezzi page.