*5.3. The Technical Maintenance Index (Itm)*

The technical maintenance condition of an asset undoubtedly represents one of the fundamental elements for planning a correct valorisation strategy, even if not in absolute terms: elements such as the dimensions of the building itself (floor areas and the size of the lot), internal heights, and architectural constraints may take priority over technical maintenance requirements in relation to possible uses. In fact, for example, proceeding with an operation of valorisation through recovery and adaptive reuse to create social welfare or tourism/hospitality activities is highly improbable when building dimensions do not respect legally defined minimum standards. The same is true when future uses are incompatible with heritage listings and conservation projects.

In any case, these aspects must be carefully evaluated: prior to this process, through an initial screening that limits the sample of assets to be evaluated and identifies those best able to satisfy particular requirements; at the end of the process, they verify the congruity of proposed strategies.

Though the technical-maintenance index (Itm) expresses a plurality of parameters, an asset's current performance level can be analysed by subdividing the seven classes of needs suggested by Italy's UNI 8289:1981 standard. Furthermore, with a view toward simplification, a dichotomic variable can be proposed for each parameter related to the presence/absence of a specific requirement, evident even during a quick inspection. The following elements were analysed:


(reinforced concrete or steel) imposes less constraints than buildings with a box-like structure (load-bearing masonry). The parameter will be set to 1 for framed structures and 0 otherwise.


The index is expressed as follows:

$$I\_{s0} = \left\{\frac{\sum\_{i=1}^{n} P\_i}{n}\right\},\tag{3}$$

