Terraces are among the most exposed surfaces of a building, constantly subjected to rain, snow, frost, and temperature fluctuations. Without proper protection, these areas are prone to water infiltration, deterioration of reinforced concrete components, and indoor issues such as dampness and mold. Implementing the right waterproofing method is essential to ensure long-term durability. So how should terrace waterproofing be done? Which methods are most effective? Below is a detailed overview of key waterproofing systems for terraces and their respective advantages.
1. Liquid-Applied Membrane Systems
Liquid-applied membranes are among the most commonly used waterproofing solutions for terraces. Typically based on polyurethane, acrylic, or bitumen formulations, these systems are applied in liquid form and cure to form a seamless, elastic, and fully adhered waterproof layer.
Advantages:
- Seamless and fully bonded to the substrate
- Easily applied around details and penetrations
- Excellent crack-bridging capabilities for hairline cracks
- Can be applied using brush, roller, or airless spray equipment
Disadvantages:
- Surface preparation is critical to performance
- Some products offer limited UV resistance, requiring a topcoat or protective covering such as tiles
Recommended Products:
Dryfix Water Block, polyurethane- and bitumen-based liquid membranes
2. Polyurea Waterproofing Systems
Polyurea is a high-performance, two-component waterproofing system applied via hot spray. It cures within seconds to form a highly elastic and durable protective coating. Ideal for both industrial and commercial structures, it is increasingly used in terrace applications.
Advantages:
- Extremely fast curing (within seconds)
- Exceptional elasticity and mechanical strength
- Outstanding resistance to chemicals, UV, and abrasion
- Performs reliably across a wide temperature range (-30°C to +100°C)
Disadvantages:
- Requires specialized spray equipment and trained applicators
- Higher cost compared to conventional systems
Best Use Cases:
Large-scale commercial terraces, roof decks over parking areas, thermal insulation-covered terraces, or where long service life is a priority
Note: 100% pure polyurea provides the highest level of waterproofing performance.
3. Bituminous Membranes
Bituminous waterproofing sheets are a traditional choice, especially favored by contractors familiar with conventional methods. Applied using a torch (torch-on method), these rolls come in 3 mm or 4 mm thicknesses.
Advantages:
- Cost-effective
- Quick installation over large areas
- Compatible with traditional waterproofing practices
Disadvantages:
- Overlaps and seams pose potential leakage risks
- Detailing around edges and penetrations can be challenging
- Limited UV resistance—requires protection layer (e.g., tiles or screed)
Application Details:
Usually installed over thermal insulation boards, followed by geotextile, screed, or a tile finishing layer for protection.
4. Crystalline Waterproofing Mortars
This method involves the use of cementitious materials that penetrate concrete and form insoluble crystals within the pores and capillaries, effectively blocking water pathways.
Advantages:
- Integrates with concrete, making the substrate itself water-resistant
- Will not crack or delaminate over time
- Effective for both positive and negative side waterproofing
Disadvantages:
- Does not form a surface coating; requires a top layer (e.g., tiles or screed) for exposure
- Performs best on freshly poured concrete
Recommended Product:
Dryfix CRYSTALLIZE—a cement-based crystalline waterproofing mortar that penetrates deeply and forms a permanent barrier against both positive and negative water pressure.
5. Under-Tile Waterproofing Systems
When tiles are planned as the final terrace finish, a reliable under-tile waterproofing layer is essential. Cement-based, brush-applied waterproofing slurries are the most widely used solution for this purpose.
Advantages:
- Compatible with tile adhesives and tile finishes
- Allows vapor permeability while ensuring waterproofing
- Provides flexibility and adhesion to the substrate
Disadvantages:
- Not suitable for exposed use—must be covered with tiles or screed
Recommended Products:
Dryfix Full Flex 2K, Dryfix Semi Flex—two-component, cementitious waterproofing products ideal for under-tile use on terraces
6. Transparent Waterproofing Coatings
For terraces where the existing ceramic finish is to be retained, transparent waterproof coatings offer a practical retrofit solution. These products block water ingress through joints and microcracks without altering the surface appearance.
Advantages:
- Preserves the existing finish—no demolition required
- Simple and economical application
- Maintains visual aesthetics due to transparency
Disadvantages:
- Requires surface preparation to ensure adhesion, especially on glossy tiles
- May need reapplication every 2–4 years for continued effectiveness
Recommended Product:
Dryfix Glassy 100—a transparent, ready-to-use waterproofing coating suitable for use over tiled surfaces without removing them
Choosing the Right System for Your Terrace
There is no one-size-fits-all solution for terrace waterproofing. The optimal method depends on various factors, including:
- Whether the terrace is newly constructed or already tiled
- Intended use of the terrace (e.g., accessible or inaccessible)
- Local climate conditions
- Budget constraints
- Expected lifespan of the system
General Recommendations:
- For new construction: cementitious under-tile systems offer reliability and cost-efficiency
- For existing tiled terraces: transparent systems like Dryfix Glassy 100 enable quick, non-invasive waterproofing
- For high-performance and longevity: pure polyurea systems deliver unmatched durability
- For economical yet effective protection: single-component polyurethane or liquid-applied membranes are suitable
Don’t let water infiltration compromise your building’s integrity. Dryfix terrace waterproofing solutions provide long-lasting, professional-grade protection against rain, UV, frost, and moisture-related issues. Choose the right system, apply it correctly, and enjoy peace of mind for years to come.
