Superbonus and shared systems: when the incentive does not apply

The Superbonus has made large-scale energy renovation projects possible, but not all buildings can access the deductions with the same ease. One of the most complex scenarios involves properties with heating, plumbing or thermal systems shared among multiple residential units or multiple owners. In these cases, the building's system configuration can make it technically or legally impossible to meet the requirements set by the legislation, effectively ruling out the benefit.

Why shared systems create problems

As a general rule, the Superbonus requires that the driving interventions — those that open the door to the deductions — concern the building envelope or the building's heating system as a whole. When the system is shared among units belonging to different owners, any work on it requires the consent of all the co-owners or condominium members involved. If this consent cannot be reached, or if the system configuration does not allow for a unified replacement or upgrade, the basic technical requirement cannot be met.

In practice, this often concerns historic or rural buildings — a very common type in the Umbrian territory, and in Todi in particular — where boilers, wells or connections were built collectively, without a clear division of the system-related appurtenances. In these contexts, even simply identifying the system to be replaced may require an in-depth technical analysis.

The cases in which the incentive does not apply

As a rule, the incentive is inapplicable or very difficult to obtain in the following scenarios:

• A single heating system serving separately owned units, with no possibility of separating the systems.
• Lack of agreement among the co-owners on the work to be carried out or on how to share the costs.
• Technical impossibility of installing individual systems (such as heat pumps or independent boilers) for each unit.
• Buildings with structural or landscape restrictions that prevent the necessary modifications to the systems.
• Absence of a pre-existing heating system, a condition which in certain regulatory configurations precludes access to the incentives.

What to do before starting the work

Before making any decision, it is advisable to engage a qualified professional — an engineer or a surveyor with experience in energy efficiency procedures — for a preliminary assessment of the building's system configuration. This step makes it possible to understand whether technical solutions compatible with the regulatory requirements exist, or whether the current configuration rules out access to the incentive from the outset.

At the same time, it is advisable to consult an accountant or a specialised tax advisor, because the conditions for accessing the Superbonus have been subject to frequent updates and can vary depending on the type of building, the number of units and the ownership structure. Your local municipality can also provide guidance on local building restrictions that might interfere with the work.

Alternative solutions worth considering

When the Superbonus is not accessible, it does not necessarily mean giving up on energy renovation. Other incentive schemes exist — standard tax deductions for renovation and energy efficiency, regional grants, subsidised financing — which can cover part of the costs, albeit with different rates and ceilings. In Umbria, certain support measures for the recovery of rural and historic building stock complement the national incentives: it is worth checking the availability of up-to-date resources with the Region or your municipal help desk.

If you are considering buying or selling a property in Todi or the surrounding area and want to understand how the system configuration affects the property's value and the options for intervention, our team is available for a no-obligation conversation. We know the territory and the specific features of the local building stock, and we can help you find your way with practical information.