Waterproofing for renovations of historical importance: effective and long-lasting solutions with Hydrostop and Siriosan

The renovation of historic buildings is not just a building restoration operation, but an act of protecting cultural and architectural heritage. In this context, waterproofing plays a fundamental role in ensuring the durability of structures and the preservation of their original aesthetics. Surfaces subject to rising damp or water infiltration, if not properly treated, are at risk of rapid deterioration, compromising both the safety of the building and its historical value.
Proind, which has been active in the field of professional building solutions for many years, offers two high-performance products designed to specifically address water-related issues: Hydrostop, for creating a chemical barrier against rising damp, and Siriosan, for waterproofing horizontal surfaces subject to infiltration.

Buildings of historical and architectural value often have construction characteristics that differ from modern buildings. Materials such as solid bricks, natural stone, tuff, lime and traditional mortars are highly porous and, over time, become increasingly vulnerable to water damage.
Rising damp can lead to:

• The formation of salt efflorescence, which alters the appearance of the walls.
• Progressive deterioration of plaster and coatings, which become detached or flake off.
• The appearance of mould, which is harmful to health and difficult to remove permanently.
• Loss of structural characteristics of building materials.

In conservative restoration projects, every intervention must be selective and reversible, and above all respect the originality and authenticity of the building. It is therefore necessary to rely on non-invasive technical products that do not alter the aesthetic appearance or compromise the breathability of the materials.

Hydrostop is a solvent-based siloxane water repellent, specially formulated to protect highly porous building materials. Thanks to its molecular structure based on oligomeric organosiloxanes, Hydrostop penetrates deep into the pores of materials, forming a hydrophobic chemical barrier that blocks capillary water rise, while leaving the breathability of the substrate intact.
Main features of Hydrostop:

• Does not alter the colour or appearance of surfaces.
• Resistant to UV rays and ageing.
• Prevents the formation of salts and mould.
• Does not form surface films (non-film-forming).
• Easy to apply even on uneven surfaces.

Hydrostop is ideal for use on stone, brick, tuff and lime-based plaster walls, both indoors and outdoors. Its effectiveness has been proven even in the most complex contexts, such as churches, noble palaces, museums and listed rural buildings.

Another common problem in restoration work is horizontal surfaces such as terraces, flat roofs, flat roofing and balconies. In these cases, water infiltration can occur silently, causing significant structural damage and leaks in the rooms below.
To solve this problem, Proind offers Siriosan, a highly reactive, solvent-based organic binary compound that can penetrate deep into concrete through capillary absorption.
Main advantages of Siriosan:

• Blocks water absorption through surface porosity.
• Penetrates deeply and reacts chemically to create a permanent barrier effect.
• Does not alter the surface appearance or compromise the adhesion of any coatings.
• Suitable for historic roofs, terraces of ancient buildings, string courses and balconies made of stone or concrete.

Siriosan is particularly useful in restricted contexts, where it is not possible to use traditional invasive waterproofing methods or where the geometry of the roof cannot be modified. Its use allows for invisible and long-lasting protection of surfaces exposed to atmospheric agents, even in the absence of sheathing or membranes.

Proind’s approach to historic renovation is based on striking a balance between technology and respect for the existing building. Hydrostop and Siriosan products offer a discreet yet highly effective solution, in line with the principles of conservative restoration.
Both products are easy to apply, compatible with historic materials, and guarantee long-term protection without invasive interventions. Thanks to these characteristics, they are used in numerous restoration projects in Italy and abroad, helping to safeguard prestigious buildings and places of collective memory.

The waterproofing of historic buildings cannot be entrusted to standard solutions. Specific products are needed, tested and developed to meet the needs of conservation. With Hydrostop and Siriosan, Proind provides designers, technicians and restorers with two fundamental tools for combating damp and infiltration, while fully respecting the construction and cultural characteristics of historic buildings.