Start with the roof, not the product
The existing roof covering, moisture condition, cohesion, slope, seams, upstands and penetrations determine which renovation is possible. A coating that functions well on one surface does not have to adhere to another roof layer without preparation.
Therefore, first determine whether the existing structure can be retained. Wet insulation, loose layers, large bubbles or structural defects may require replacement or targeted repair.
- Substrate and existing layers
- Moisture and stability
- Slope and water tax
- Details and movement
- Accessibility and use
Three technologies with different strengths
Cold-applied 2K polyurea is interesting for a robust complete renovation where mechanical performance, detailing and controlled layer build-up are important. A fast drying water-based PU can be suitable where very low VOC, short recoat times and early rain resistance are important.
Specialized silicone systems may also be appropriate within demonstrably suitable applications. Never judge the product family alone: primer, consumption, layer thickness, detailed structure and technical documentation also determine the performance.
Ask for a complete system description
A professional offer describes preparation, repairs, primer, detail reinforcement, membrane layers, material consumption and application limits. It must also be clear which assumptions still need to be confirmed after inspection.
A low price per square meter without this information is difficult to compare. The most useful quotation makes visible why the system fits the actual roof.
- Preparation method
- Primer per surface
- Detail treatment
- Consumption and number of layers
- Weather and moisture limits
- Maintenance and repairability
This explanation is general and does not constitute project-specific system advice. Subsurface investigation, tax and official system documentation remain decisive.