Technical criteria, construction conditions, and recommendations from Krypton Chemical experts
Introduction
When renovating a roof, choosing the right waterproofing system is not just a question of price. Factors such as sun exposure, the type of substrate, the climate, and the construction schedule can determine the success of the project.
In the case of sprayed polyureas, the decision between pure polyurea and hybrid polyurea requires an understanding of how each behaves in real application conditions. Both guarantee continuous, joint-free waterproofing, but they respond differently to humidity, temperature, and traffic.
In this article, we analyze the practical selection criteria and recommendations that Krypton Chemical‘s technical team applies in renovation projects around the world.
Application conditions: humidity, temperature, and timing
The first variable to evaluate is always the application environment.
- If the project involves damp substrates, condensation, or areas that are difficult to dry (such as old roofs with asphalt layers or absorbent mortars), pure polyurea is the safest option. Its 100% reaction with amines prevents problems such as bubbling or lack of curing.
- In contrast, hybrid polyurea requires more controlled and dry conditions, making it ideal for interior projects or renovations with greater scheduling flexibility.
In terms of time, pure polyurea allows the roof to be put back into use in less than an hour, which is crucial in logistics or industrial facilities where every minute of downtime counts.
Sun exposure, transit, and maintenance
Another determining factor is exposure to sunlight and pedestrian or technical traffic.
- Walkable roofs or roofs exposed to intense UV radiation require pure aliphatic polyureas or hybrid systems protected with an aliphatic polyurethane top coat to ensure color stability and resistance to aging.
- On non-trafficable roofs, technical areas, or areas requiring occasional maintenance, a hybrid polyurea with a protective finish is sufficient, reducing the total cost without compromising waterproofing.
Maintenance planning also plays a role: while pure polyurea can offer more than 25 years of durability, a hybrid coating usually requires surface recoating in the medium term.
Type of support and structural movement
Not all substrates behave in the same way. In renovation projects, it is common to find a combination of concrete, ceramic, or polyurethane foam, and even areas with differential movement.
Pure polyurea, thanks to its high elongation (>400%) and excellent adhesion, absorbs these movements better without cracking the waterproof layer.
On the other hand, hybrid polyurea, although also elastic, responds better on more stable or level substrates, such as flat concrete or prefabricated roofs.
In both cases, a specific primer is key to ensuring adhesion and continuity between old and new layers.
Budget, performance, and life cycle
The economic comparison cannot be limited to the cost of the material per square meter.
Pure polyurea requires high-pressure spraying equipment and specialized personnel, which increases the initial cost. However, its performance and durability offset the investment in projects where the work cannot be easily repeated (industrial warehouses, logistics roofs, or communal terraces).
Hybrid polyurea offers an ideal balance in residential or periodic maintenance projects, where the customer values ease of application and cost optimization.
In summary:
- Pure: high investment, minimal maintenance, extended service life.
- Hybrid: medium investment, scheduled maintenance, excellent cost/benefit ratio.
Conclusion
The choice between pure and hybrid polyurea is not a question of “better or worse,” but rather one of technical suitability for the context of the project.
Both technologies offer outstanding results when properly formulated, applied, and monitored. The difference lies in the objectives of the project:
- Maximum demands, exposure, or humidity → pure polyurea.
- Maintenance or light refurbishment projects → hybrid polyurea.
Contact us and our technical team will advise you personally to find the most efficient and durable solution.
At Krypton Chemical, we help you select the optimal system for your needs, guaranteeing professional results and waterproofing without surprises.
