From time immemorial, humans have taken inspiration from nature to drive innovation. The practice of emulating elements of nature to solve complex human problems is called biomimicry, and its application can be seen in anything from aerodynamic vehicles to bacteria-resisting surfaces and many other examples.
Sto Corp.’s Lotus-Effect® is one of them. Named after the lotus leaf’s superhydrophobic surface and self-cleaning mechanism, it mimics nature’s solution to the problem of dirt – working as elegantly on building envelopes as it does on delicate leaves.
While the underlying technology behind Sto’s Lotus-Effect remains the same throughout, Sto translated the principle into two products: StoColor® Lotusan® and Stolit® Lotusan®. Both solutions apply the same biomimetic concept; each offers a different type of solution.
The Science Behind the Lotus-Effect
Before we get into the difference between Sto’s two product offerings using the Lotus-Effect, let’s go over what it is and how it works.
Lotus leaves have a micro-structured surface that creates air pockets under water droplets. This reduces the contact area between water, dirt particles and the surface. Instead of spreading or soaking, water beads up and rolls off, carrying surface contaminants and dirt away with them.
Sto’s Lotus-Effect works in much the same way on a building envelope, providing multiple benefits:
- Reduced biological growth
- Faster drying after rain or dew
- Extended service life and color retention
Both products are vapor permeable, allowing water vapor to pass through the applied finish or coating. This supports the drying potential of properly designed wall assembles and helps reduce the risk of blistering associated with trapped vapor.
StoColor Lotusan — The Coating
StoColor Lotusan, one product option featuring the Lotus-Effect, is a high-performance exterior wall coating for recoating over existing facade finishes, coating of new substrates outside an integrated Sto wall system, or building restoration/rehabilitation projects. It can be applied over concrete, stucco, EIFS, fiber cement board, and primed or pre-painted wood surfaces.
StoColor Lotusan is best used when the surface texture is already established or not desired. It works great for an aesthetic refresh with an added self-cleaning performance upgrade.
Some features of StoColor Lotusan:
- Flat sheen
- Tintable in a variety of colors
- Vapor permeability
- Highly resistant to soiling, pronounced self-cleaning effect
- Excellent weather and chalk resistance
Stolit Lotusan — The Textured Finish
Stolit Lotusan, the other Lotus-Effect facade solution from Sto, is a textured, ready-mixed synthetic finish coat used as the visible finished layer for Sto wall assemblies, such as StoTherm® ci and StoPowerwall® or as a textured finish layer over existing prepared vertical concrete, masonry or plaster substrates in new construction or renovation projects.
Some features of Stolit Lotusan:
- Combines Lotus-Effect self-cleaning performance with the full Sto textured finish range.
- Offers design flexibility without compromising long-term facade cleanliness and weather resistance
- Available for dark or saturated colors
- Lasting uniform color
- Improved resistance to mold, mildew and algae
How to Choose
Choosing between Sto’s Lotus-Effect facade coating solutions depends on the substrate, desired texture and wall system application.
Choose StoColor Lotusan for:
- Façade recoating and restoration projects where the texture is established or not desired
- New construction projects that desire self-cleaning Lotus-Effect to minimize soiling and extend service life.
Go with Stolit Lotusan for:
- New Sto wall systems desiring textured finish with self-cleaning performance
- StoTherm® ci
- StoPowerwall® ci
- StoPanel® Prefabricated Wall Systems
- StoVentec® Render
- StoQuik® Silver
- Sto Specialty Systems
- Prepared existing walls wanting textured finishes with self-cleaning performance
For mixed conditions, such as new wall systems combined with existing structure renovations, or the use of saturated or dark colors, Sto’s technical consultation team provides support from project design to completion. They can help coordinate products based on the specific project to achieve a seamless aesthetic continuity and single-source system performance.
One Principle, Engineered for Two Realities
The Lotus-Effect is a proven, single piece of biomimicry bringing nature’s engineering to building envelope technology. Sto’s family of products translates this concept to fit any situation. Whether it’s StoColor Lotusan, Stolit Lotusan or a combination, there’s a solution to keep facades clean, durable and dry for every project.
Ready to add nature’s self-cleaning innovation to your next project? To learn more about Sto’s family of Lotus-Effect solutions, check out StoColor Lotusan and Stolit Lotusan’s product pages, or take a look at the Project Gallery to see some real-world applications here and here.
For expert color, texture and substrate guidance, reach out to Sto’s technical support team here.
