Overbuilding: building permits and technical formalities

Overbuilding a building lives on two parallel tracks. On one side are the civil-law limits of Article 1127 of the Italian Civil Code, concerning the relationship between the person building and the other owners: structural conditions, architectural appearance, air and light, indemnity. On the other side are the public and building-law formalities, that is, the required permits, compliance with technical and planning rules, and cadastral obligations. Ignoring either track exposes the project to civil disputes or administrative penalties.

The required building permit

Overbuilding, since it creates new volume and transforms the building, is among the more significant works governed by building regulations. In general it requires a permit at a level appropriate to the scale of the work, which in many cases is the building permit (permesso di costruire). The precise classification depends on national and regional legislation, the municipal building regulations and the features of the work. It is therefore necessary to engage a qualified technician to identify the correct permit and prepare the application to the municipality.

Structural and seismic aspects

Respecting the structural conditions required by Article 1127 translates, technically, into verifying the building's capacity to bear the new loads. Overbuilding affects the structural behaviour of the whole building and, in seismic zones, entails specific safety assessments and formalities. A structural designer must check the foundations and load-bearing structures, plan any reinforcements and produce the required documents. The safety of the entire building, not just the new floor, is the guiding parameter.

Distances, heights and planning parameters

The new construction must respect the applicable planning and building parameters: maximum permitted heights, distances from boundaries and neighbouring buildings, buildability indices and any constraints on the context. These parameters are set by the municipal planning instruments and the relevant legislation. An overbuilding that exceeds the permitted height or violates distances is unlawful even if it respects the civil-law limits among owners. A prior check avoids carrying out works destined for demolition or regularisation.

• identify with a technician the building permit appropriate to the work
• carry out the structural checks and the required seismic formalities
• check maximum heights, distances and planning indices
• verify the presence of landscape or heritage constraints on the building
• plan the cadastral update of the new unit or layout

Constraints and protected contexts

If the building lies in an area subject to landscape, heritage or environmental constraints, overbuilding may require further authorisations issued by the competent authorities. In such contexts the protection of the asset and the landscape adds to the ordinary assessments and can strongly limit the possibilities of intervention. It is essential to ascertain the presence of constraints from the earliest design stages, so as not to start a process destined to stall or to impose solutions very different from those envisaged.

Coordinating applications and communications in the condominium

An overbuilding involves technical applications, authorisations and communications to owners that are best kept orderly and tracked, both for transparency and in view of possible challenges. The manager has an interest in storing the building's documentation in an organised way and recording relevant communications. With a management platform such as AmministraPro the manager can archive projects and authorisations and manage communications with owners in a tracked way; the features are described on /funzioni, while plans and costs are on /prezzi.