Foundations are among the most critical structural elements of a building. Once construction is complete, it can be difficult to inspect them, and even more challenging to fix any problems. This is why waterproofing must be considered right from the design stage and applied rigorously from the very start of construction.
Inadequate concrete waterproofing increases the risk of water and moisture infiltration. These issues often lead to premature degradation of materials, not to mention the hazards of mould, which can affect the health of the occupants.
A Challenging Canadian Environment
In Canada, the climatic and operational context (thermal cycling, hydrostatic pressure, and suboptimal conditions) puts waterproofing systems to a severe test. Freeze-thaw cycles, high humidity, uneven surfaces and tight deadlines mean that it is essential to have a waterproofing solution that is not only effective but, above all, easy to install.
This is why liquid waterproofing membranes are gaining popularity. They offer a continuous, joint-free barrier that conforms to any surface irregularities. This represents a major advantage when foundation details are complex or installation takes place in less than perfect conditions.
Why Choose a Liquid Waterproofing Membrane on a Conventional Foundation?
Compared to sheet membranes, the main benefit of a liquid system lies in the speed of installation. It can be applied by spraying, which allows large areas to be covered quickly and significantly speeds up the process. For smaller areas, application with a roller is also possible. One of the key strengths of liquid membranes is their ability to adapt to irregularly shaped surfaces. They conform more easily to uneven areas, something that is more difficult to manage with a sheet membrane, which is more rigid. Furthermore, the absence of joints reduces the number of critical points and decreases the risk of infiltration associated with details.
Limitations of Liquid Membranes
Liquid waterproofing membranes also have certain shortcomings: some are unsuitable for environments with high hydrostatic pressure, require strict control of thickness and are sensitive to application conditions (imminent rain, contamination of the substrate, etc.). Being aware of these limitations helps in selecting the appropriate technology.
The Importance of the System as a Whole
A waterproofing membrane, liquid or not, never acts alone. Drainage, mechanical protection, insulation boards and product compatibility directly influence overall performance. A holistic approach reduces risks and optimizes the longevity of the system.
In summary:
- For buildings with more than 3 stories and a surface area exceeding 600 m², a dampproofing solution is acceptable only if the drainage system unequivocally eliminates any risk of infiltration.
- If there is any doubt, full waterproofing is generally required.
- A dampproofing solution cannot be used if the foundation slab is not cast in place.
However, in the majority of projects, these ideal conditions are not met. Hence the need for a reliable waterproofing membrane in most situations.
Choosing the Right Technology
Selecting a liquid membrane involves several factors: application temperature, substrate moisture content, complexity of details, schedule, and desired adhesion. The decision requires balancing performance, site conditions and target durability.
Comparative table of technologies
| Dampproofing | Waterproofing | |||||
|---|---|---|---|---|---|---|
| Non-fibrous bituminous coating | Bituminous emulsion | Polyurea | STPE elastomer | |||
| Resistance to hydrostatic pressure | Dampproofing | No | Waterproofing | No | Yes | Yes |
| Cost of the installed product | Dampproofing | $ | Waterproofing | $$ | $$$ | $$$ |
| Age of concrete | Dampproofing | Green concrete | Waterproofing | Green concrete | Green concrete | Green concrete |
| Curing time | Dampproofing | 12 to 24 hours | Waterproofing | ± 24 hours | 10 seconds | 60 minutes |
| Main uses | Dampproofing |
|
Waterproofing |
|
|
|
| Main benefits | Dampproofing |
|
Waterproofing |
|
|
|
| SOPREMA product | Dampproofing | COLPHENE LM 1100 | Waterproofing | COLPHENE LM 3200 | COLPHENE LM 3500 | COLPHENE LM BARR COLPHENE LM BARR SPRAY |
Conclusion
The waterproofing of foundations is never a mere technical detail: it is an assurance of durability. Liquid membranes offer a flexible, continuous solution adapted to Canadian conditions. Understanding their benefits, limitations, and governing standards enables professionals to make informed choices and effectively protect buildings for decades to come.