Indice
Large Concrete Infrastructure: Waterproofing with Unibar F
A 10,000 m³ Underground Detention Tank Protected with a High-Performance Epoxy System
Extreme weather and intense rainfall events are increasingly challenging urban hydraulic systems. Detention and retention infrastructures have become essential for preventing flooding, safeguarding urban areas, and ensuring the efficiency of municipal drainage networks
In Parabiago (Lombardy), a major hydraulic engineering project was successfully completed: a 10,000 m³ underground stormwater detention tank designed to capture excess water during heavy rain and release it gradually into the municipal drainage system
To ensure long-term waterproofing, durability, and protection of the concrete structures, the project team selected UNIBAR F by Winkler Chimica, a high-performance epoxy waterproofing system specifically engineered for demanding, moisture-rich environments.
Project Context and Objectives
The Parabiago detention tank is a large underground water-storage structure built beneath a parking area that includes:
- 36 parking spaces
- Landscaped green areas
Project dimensions:
- Storage capacity: 10,000 m³
- Treated surface area: 1,500 m²
- Depth: 8 meters
L’obiettivo primario dell’intervento era assicurare una tenuta idraulica perfetta e proteggere l’integrità del calcestruzzo dai cicli continui di riempimento e svuotamento, garantendo la continuità del servizio idraulico cittadino.
Structural Challenges of the Concrete Tank
Waterproofing underground hydraulic infrastructure of this scale significant technical challenges:
- Constant humidity: Being underground, the structure is continuously exposed to moisture – conditions under which conventional coatings often fail
- Hydrostatic pressure: The tank must withstand both internal (water stored inside) and external (soil groundwater) hydrostatic forces
- Absence of a vapour barrier: Without a vapour barrier, the waterproofing system required must be breathable, allowing vapour transmission without blistering or detachment
- Chemical exposure: Stormwater may contain:
- Hydrocarbons
- Acidic or alkaline residues
- Suspended pollutants
All of which can gradually deteriorate unprotected concrete.
The Solution: Unibar F Waterproofing System
To overcome these challenges, the project team selected Unibar F, a two-component epoxy coating with high breathability, engineered for cementitious substrates exposed to humidity and without a vapour barrier.
Technical Application Details
The application followed a precise, certified procedure:
- Surface preparation: Complete cleaning and substrate preparation to ensure maximum adhesion
- Application of UNIBAR F
- Two coats in grey
- Consumption> 400–500 g/m²
- Versatile installation Methods
- Roller application for large horizontal and vertical surfaces
- Brush application for corners, pillars up to 7 meters high, and detailed structural elements
Technical and Environmental Advantages
Using Unibar F delivers high-level performance while meeting sustainability requirements.
- Waterproof yet breathable:
Allows vapour to escape from the substrate while blocking liquid water- preventing detachment or blistering.
- Strong resistance to chemical aggression
Ideal for environments containing diluted acids, alkalis and salts – typical of urban runoff water.
- Exceptional adhesion
Forms a durable chemical-mechanical bond, even on damp concrete
- Winkler-Safe approach:
A solvent-free, low emission formulation that ensures:
- maximum safety for applicators
- minimal environmental impact
Results and Benefits Achieved
The waterproofing works were completed on schedule and delivered both immediate and long-term benefits:
- Long-lasting protection:
Increased structural durability and resistance to chemical and mechanical wear.
- Cost efficiency:
Fast installation and reduced labour times helped optimize project costs
- Simplified maintenance
Smooth, protected surfaces allow easier inspection, cleaning, and upkeep
- Reliable hydraulic performance
The system guarantees watertightness and continuity of municipal stormwater management operations
FAQ – Frequently Asked Questions
1. Why was Unibar F chosen for this underground tank?
It is specifically engineered for constant humidity environments and can withstand internal/external hydrostatic pressure.
2. Can it be applied without a vapour barrier?
Yes. Its breathable formulation is ideal for damp substrates where traditional coatings may fail.
3. Is it resistant to aggressive or chemically aggressive water?
Absolutely. It protects concrete from diluted acidic, alkaline, and saline solutions commonly found in stormwater.
4. Is it suitable for large areas such as 1,500 m²?
Yes. Its versatility allows efficient roller and brush application even on large and complex surfaces.
5. What long-term benefits does it provide?
Durability, reduced maintenance, and long-term watertightness throughout the structure’s service lifezazione per grandi opere idrauliche?
