Renovation of a historic building with expansion and creation of a parking lot near Lecco

The historic building underwent various types of intervention:
<ul>
<li>The base portion and the elevator room in contact with the groundwater;</li>
<li>The walls against the mountain with water infiltration;</li>
<li>The external walls.</li>
</ul>

For this part of the project, we chose to adopt the PROIND technology of the SIRIOBARRIERA System, based on the use of catalyzed silane monomers formulated for the treatment of absorbent yet vapor-permeable building materials. This system prevents capillary rising damp in masonry thanks to the use of SIRIOBARRIERA WR.

SIRIOBARRIERA WR, formulated with water and therefore odorless, is inserted into the masonry using a pressure injection, creating a horizontal barrier capable of blocking capillary rising damp.

At the same time, dehumidifying mortars are used, such as SIRIOBETON IDR, a smoothing plaster compliant with UNI EN 998-1, which provides excellent dehumidifying and masonry restoration capabilities. The product has very low resistance to vapor diffusion and excellent water vapor permeability (μ ≤ 15); these characteristics allow the masonry to expel water in the form of vapor in quantities generally greater than that absorbed by capillary action.

IRIOBETON IDR is also formulated to provide a water-repellent coating. Its fire reaction class is A1, while water absorption is ≥ 0.3 kg/m² after 24 hours.

For the finishing of the internal and external walls, RASOCAL mortar was used. This ready-to-use mortar complies with (GP)(CS III W1) UNI EN 998-1, in Class 5.0 (NHL 5 natural hydraulic lime for smoothing rough plasters, completely free of pozzolanic materials, blast furnace slag, fly ash, or hydraulic binders of any kind (clinker, cement, etc.). It consists of hydrated mono- and dicalcium silicates, specific wetting agents, controlled-grain aggregates, and additives to promote adhesion and workability.

The total absence of salts, chemicals, and volatile organic compounds, combined with the completely mineral nature of the components, guarantees purity, non-toxicity, harmlessness, and complete recyclability. The unique characteristics of Pure Natural Hydraulic Lime NHL 5, such as its slow hardening process and continuous increase in strength over time, Mechanical properties, combined with a low elastic modulus, provide elasticity to products made with it, differentiating them from those made with lime or cement-based products. The use of NHL 5 allows for perfect adherence to the ancient building techniques used in restoration and green building.

The porosity of NHL 5 Natural Hydraulic Lime ensures high water vapor diffusion, provides breathability to the substrate, allows for the elimination of absorbed water, and regulates environmental humidity, preventing the formation of harmful condensation and mold. The high basicity of the mixture (pH = 12.5) makes surfaces resistant to biodegradable agents and prevents their proliferation, creating hostile conditions for the survival of pathogenic microorganisms (bacteria, fungi, viruses) that cause infections, diseases, or allergic reactions. Products obtained with only the NHL 5 binder, being entirely mineral, do not constitute “special waste.”

Applicable to all substrates, mainly in very thin layers (1-2 mm) without showing problems of rapid water evaporation; high breathability and excellent adhesion to the substrate.

It has a high level of finish: it can be left as is or painted with highly breathability paints.