Chimney maintenance and repointing involve the careful structural preservation and weatherproofing of brickwork, lead flashing, and stack masonry exposed above the roofline. As the highest and most vulnerable feature of a property, chimneys are constantly subjected to punishing freeze-thaw cycles, fierce wind loads, and aggressive flue gas condensation. Far beyond being a traditional architectural focal point, a well-maintained chimney is critical for safely venting harmful combustion gases away from living areas while keeping the roof vault watertight. When mortar joints crumble, brickwork spalls, or lead flashings fail, water leaks directly into internal walls and timber joists, causing serious masonry degradation, internal plaster dampness, and structural instability.