Most roof waterproofing projects have one primary objective: preventing water intrusion. In more complex cases, aesthetic concerns must also be addressed. A prime example of this is the recent restoration of the Marin County Civic Center’s iconic blue roof. Sometimes, however, roofs do more than protect buildings and add visual interest: they serve as functional spaces. This is the case at École Notre Dame Des Victoire, where roof waterproofing is no ordinary task.
The Challenge: Multifunctional Roofing
École Notre Dame des Victoires (NDV) is a private Catholic school located at 659 Pine Street in San Francisco. Also known as “The Little French School downtown”, the French language school was founded by French Marist Fathers in 1924 and currently serves over 300 students in grades K-8.
To fulfill its commitment to nurturing students and offering a diverse array of enriching experiences in an urban environment, NDV has to be thoughtful in how it uses space. This includes creating a playground on an elevated roof deck above usable, occupied space.
While this multifunctionality is a smart solution for providing outdoor activities in San Francisco’s district, it presents unique challenges for building maintenance and repair, as the roof must reliably protect the building itself as well as occupants below and directly on top of the surface. So when the waterproof roof membrane failed in 2020, the waterproofing experts at Rainbow had to get creative.
An Innovative Roof Waterproofing Solution
Roof waterproofing systems can vary greatly in material, durability, and quality. Usually, however, they don’t have to serve as an inviting play surface for children. At NDV, ensuring that the roof deck could continue to safely fulfill its dual purposes therefore required a different approach than most roof waterproofing projects.
To begin, the original roof membrane was removed. The Rainbow team, led by Chris Abell, then repaired cracks and spalls in the concrete to ensure structural integrity and solid performance. While this is critical in any location, concrete repair takes on particular significance in the San Francisco Bay Area, where seismic tremors can easily compromise concrete structures.
Working with a representative from Sika, an innovative roof waterproofing system was then developed to keep the area watertight while simultaneously providing a user-friendly playground surface. This involved two stages:
- Sika’s Sikalastic RoofPro System, a single-component, cold-applied, moisture-triggered polyurethane membrane, was installed over the 6,400 square foot concrete roof deck. RoofPro is a cost-effective solution that forms a seamless, watertight surface that retains flexibility at low temperatures and is easily recoated without the need for stripping.
- After the RoofPro system cured, it was overlaid with SportMaster ColorPlus™, a high-quality sport surface commonly used for tennis courts and other high-impact athletic courts. This resilient, fade-resistant acrylic surface offers vibrant color, consistent texture, and impressive longevity in a variety of weather conditions—all invaluable for a playground that sees daily use in downtown San Francisco.
Together, these materials offer a durable system that meets NDV’s multiple needs.
The roof waterproofing system at NDV offers durable protection against water intrusion while providing a safe and colorful playground surface for students.
Working With the Experts
Whether you are working with new construction or protecting a historic building, choosing the best waterproofing company matters. Rainbow’s years of experience and partnerships with industry-leading vendors allow us to confidently take on unique and complex roof waterproofing projects. By offering a full range of waterproofing and restoration services—including creative custom solutions—across the San Francisco Bay Area, our team can ensure that your project is a success and your building is protected for years to come.
Rainbow is the premier roof waterproofing company in the San Francisco Bay Area. Reach out to the Rainbow team today.
The Rainbow Team is Northern California’s most trusted waterproofing and restoration company. We have the craftsmanship and expertise to handle any commercial or historic building envelope, masonry, or waterproofing project in the San Francisco Bay Area.
