What sort of climatic restrictions should I know about in Maryland as it relates to historic slate roofing?
February 29, 2024Do I have to replace all the flashings when I replace my old slate roof?
February 29, 2024One of the most important factors in flashing options is lifespan. After all, you don’t want to install a roof that can last 100 years only to have the flashings fail after just 25 or 30 years. Copper is the most common metal that we use in historic roof work and is most often required to meet historic qualifications. The weight of the copper (thickness) is also important. We use 20oz copper for most flashings, or 16oz copper where the flashing will receive less water run-off.
Heavy gauge stainless steel flashing will last even longer than copper but is not usually used because of its appearance. Aluminum has a shorter lifespan and should only be considered for asphalt shingle roofs. While it may be tempting to opt for cheaper metals up front, the savings are negligible as labor costs typically outweigh any savings on materials.