Chimney Removal in the Seattle Area, WA.

There comes a point where keeping a chimney stops making sense. The fireplace has not been lit in a decade, the stack needs a crown, a cap, repointing and new flashing, and none of that buys anything you use. In Western Washington there is a second argument too: an unreinforced masonry chimney is one of the least earthquake-tolerant parts of an older house, and the ones that come down in a shake tend to come down through the roof.

Removal comes in two forms and the difference matters. Taking the stack down to the roofline is the common one: everything above the roof goes, the roof is framed over and closed up with matching material, and the structure below stays where it is, usually boxed into the house anyway. Full removal takes the chimney out from the foundation up, which means the floors, walls and ceiling it passed through have to be framed, insulated and finished, and anything that was bearing on it has to be carried another way.

That last point is the one that gets missed. In older houses, floor joists and sometimes rafters bear on the chimney mass, and the stack may be carrying more than its own weight. Removing it without replacing that support is how a removal becomes a structural problem. There is also the fireplace to decide about, the roof to make watertight and match, and, where the chimney served gas or oil appliances, their venting to resolve before anything comes down.