The answer to 'best flashing' is that high-quality metal flashing is generally considered the best option for roofing systems. Metal flashing, such as aluminum or galvanized steel, is durable, weather-resistant, and helps create a watertight seal around roof penetrations, edges, and transitions. It is an essential component of a well-designed and long-lasting roof.
Metal flashing is preferred over other materials like plastic or rubber because it is less prone to cracking, warping, or deterioration over time when exposed to the elements. It can also be easily shaped and molded to fit complex roof features and details. Proper installation of metal flashing is critical to ensure it effectively diverts water away from the roof and protects the underlying structure.