Practical guide
Managing seismic upgrade of the building
The seismic upgrade of a residential building is a major structural intervention that follows a defined path: technical assessment, an assembly resolution passed with the correct majority, management of the applicable tax incentive, allocation of costs among the co-owners, and monitoring of progress through staged work certificates. Each phase has its own rules and practical consequences for building accounting. This guide walks through the process in order, from the initial seismic vulnerability assessment to final reporting, focusing on the points where property managers and owners most often make mistakes: the majority required, the correct allocation of costs, and the documentation that must be kept for the tax benefit.
Seismic assessment as the starting point
Before any resolution can be passed, a qualified professional must assess the building's seismic vulnerability, establishing its risk class according to the guidelines linked to the seismic tax incentive. The assessment identifies the actual structural weaknesses (masonry, floor slabs, connections between elements) and distinguishes between seismic improvement works and full seismic upgrade works, which have different technical requirements.
The property manager needs an assembly resolution to appoint the professional, even just for the assessment phase: it is generally an ordinary administration matter when limited to the survey, but it is still worth informing all owners in writing before proceeding, so the mandate is clear and documented from the very start of the process.
The assembly resolution and required majorities
Seismic upgrade works on common parts fall within the innovations governed by Article 1120 of the Italian Civil Code, which explicitly favors works aimed at seismic improvement and upgrade, requiring only the majority of those present representing at least one third of the building's value on second call. This is a lighter majority than for other innovations, precisely because structural safety is treated as a priority.
The resolution must clearly state the scope of the works, the estimated cost, whether the tax incentive will be used, and the cost allocation criteria. A generic agenda item about renovation works, without naming the specific seismic intervention, exposes the resolution to the risk of being challenged for lack of proper information to absent or dissenting owners.
- Notice of meeting with the professional's technical report attached
- Agenda item explicitly naming the seismic upgrade
- Cost estimate and allocation plan included
- Minutes recording the majority reached under Article 1120
Tax incentive: requirements and managing the deduction
The seismic tax incentive allows a deduction on expenses for seismic works on common parts, with percentages varying according to the risk class reduction achieved. The deduction applies to the total amount spent by the building and is allocated among owners according to their ownership shares, unless a different criterion is resolved.
To keep the benefit, documentation must be organized from day one: the professional's certification before and after the works, the assembly resolution, invoices addressed to the building paid through a traceable bank transfer, and the required technical communication when applicable. The property manager acts as custodian of this documentation and must keep it well beyond the end of the works, since the tax authority can request it during checks covering all the years the deduction is spread over.
Allocating costs among the owners
The general criterion for innovations on common parts is allocation according to ownership shares, under Article 1123 of the Civil Code, unless the works concern a part of the building that serves the owners in a differentiated way, in which case the differentiated use criterion under the same article applies. If the building has several staircases or separate blocks with separate ownership shares, the resolution must clarify which basis the expense is calculated on.
Building management software that tracks ownership shares by staircase and block, in addition to the general ones, simplifies this phase: AmministraPro allows the correct allocation to be set up already at the estimate stage and generates allocation plans consistent with the resolution, reducing the risk of disputes over the amount charged to each owner.
Staged progress certificates and reporting
Seismic upgrade works typically span several months or years and are paid based on staged progress certificates: each certificate confirms the percentage of work completed and authorizes payment of the corresponding share to the contractor. The property manager must verify that each certificate is signed by the works supervisor, matches the approved bill of quantities, and is consistent with the financial plan approved by the assembly, before proceeding with payments and related requests to owners.
In the building's financial statement, each staged certificate should be recorded as a separate item, referencing the resolution that authorized the overall expense: this lets owners follow the actual progress of the works and lets the property manager demonstrate, if requested, that amounts paid match the works actually completed at that point.
Frequently asked questions
What majority is needed to approve a seismic upgrade?
For seismic improvement or upgrade works on common parts, the favorable majority under Article 1120 of the Civil Code applies: on second call, the majority of those present representing at least one third of the building's value is enough. This is a lower threshold than for other innovations, because the legislator explicitly favors this type of intervention linked to structural safety.
Is a dissenting owner still required to pay their share?
Yes. Since this is an intervention on common parts approved with the majority required under Article 1120, the resolution is binding also on absent or dissenting owners, who remain required to pay their share calculated according to ownership shares or the different criterion resolved. Dissent may lead to challenging the resolution within the legal deadlines, but not to a unilateral refusal to pay.
How is the tax incentive allocated among owners who paid different shares?
The tax deduction follows the same allocation criterion as the expense approved by the assembly, normally the ownership shares: each owner deducts the share of expense actually charged to them under the approved allocation plan, not an equal share for everyone. The property manager provides owners with certification of the expenses individually incurred for their tax return.
What happens if a staged progress certificate does not match the work actually done?
The property manager should not authorize payment if the works supervisor does not confirm that the certificate presented matches the actual state of the works: paying for a percentage not completed exposes the building to the risk of advancing funds to the contractor without any guarantee of completion, and can expose the property manager to liability toward owners for mismanaging the mandate.
Does software like AmministraPro help manage this kind of intervention?
Yes: it allows the assembly resolution to be linked to the allocation plan, keeps track of the correct ownership shares even when there are multiple staircases or blocks, records each staged progress certificate as a separate item in the financial statement, and keeps the documentation needed for the tax incentive organized, so the full history of the intervention is always available if checked.
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