What a hard Connecticut winter does to a chimney
A West Hartford chimney earns its keep through some of the coldest, wettest months in the lower forty-eight, and the two forces that wear it out are creosote on the inside and water on the outside. When you burn wood through a long winter, the smoke cools as it rises and leaves a tar-like residue called creosote clinging to the flue walls. Burn often, burn the slow smoldering fires that a cold house tempts you into, or burn wood that has not fully seasoned, and that residue builds into a hard, shiny glaze. Creosote is fuel. Enough of it, and a stray spark or an overfired flue turns it into a chimney fire that can crack the liner and spread into the framing of the house. The only real defense is keeping the flue swept clean so the fuel never accumulates.
Water is the slower enemy, and around here it is relentless. Rain and snowmelt soak into the brick and the mortar all winter, then the temperature drops and that trapped moisture freezes and expands, prying the joints open a fraction at a time. This freeze-and-thaw cycle is brutal on the old masonry chimneys that crown so many West Hartford roofs, and over enough winters it spalls the brick face, crumbles the mortar crown at the top, and lets water run straight into the system. A cracked crown or a missing cap turns the whole chimney into a funnel, and the damage compounds quietly until a interior wall stain or a falling chunk of brick finally gives it away.