Flashing a chimney on a silicone roof coating involves carefully creating a waterproof barrier where the chimney meets the roof to prevent leaks. Silicone coatings are flexible and durable, but because they form a continuous membrane rather than using traditional roofing materials, the flashing technique must accommodate this unique surface. Start by applying metal counter-flashing to the chimney, which is stepped or layered to direct water away from the joint. The step flashing pieces should tuck under the silicone coating and overlap each other like shingles to channel water down the roof. The key is to ensure each metal piece is securely fastened to the chimney and integrated into the coating without gaps. You might notice water stains or soft spots inside, or see the silicone membrane peeling or cracking near the chimney, indicating flashing issues. A simple DIY check involves inspecting the flashing lines for rust, separation, or silicone wear, and watching for drips after heavy rain.
If you detect any issues beyond surface wear, it’s best to call a roofer experienced with silicone coatings and metal flashing. Asking, “How do you ensure a long-lasting seal between the silicone membrane and metal flashing?” and “What warranty do you offer on chimney flashing repairs involving silicone roofs?” can help clarify their approach and reliability. Because silicone coatings expand and contract with temperature, a roofer needs to use methods and materials compatible with these changes to avoid leaks or membrane damage. Correct installation should also comply with the coating manufacturer’s warranty terms to avoid voiding coverage. While small crack repairs can be DIY with proper silicone sealant, flashing near chimneys usually requires professional skill for secure fastening, seamless integration, and durable water protection.