Successful balcony and rooftop waterproofing begins with a stable, properly prepared surface. Cracks, damaged sections and unsuitable existing coatings may need to be repaired or removed. The membrane must be carefully applied around edges, corners, drains, thresholds and penetrations. These areas require particular attention because even a small gap can provide a path for water. The selected system should also suit the location, surface and level of weather exposure. Rooftops and balconies may require different approaches depending on whether they will be tiled, covered or left as an exposed membrane finish.