Chimney and Fireplace Service in Salt Lake City

Built for coal, handed something else

The brick grid around downtown and up through the Avenues went in when a household burned coal in the fireplace itself. A coal flue is narrow, and it was expected to run hot. When those chimneys were later given a wood fire, a gas log set, or a furnace connector teed into the side, nobody resized anything. The flue stayed exactly the size it had always been while the appliance underneath it changed two or three times.

That mismatch explains most of what we find. Too much cross-section for a modern gas appliance and the exhaust cools on the way up and condenses inside the masonry. Too little draft for an open wood fire and you get smoke rolling into the room on a still, cold morning, which owners usually blame on the wood.

Height, and what it costs

Stacks here run taller than anywhere else in the valley, often two or three stories of unreinforced brick standing clear of the roofline with nothing bracing it. The ground underneath is seismically active. The top few courses are also the part that has been soaking and freezing for a century, frequently under a sloped skim of mortar rather than a real crown. When we inspect an older chimney in this city we want to see the top first, because both of those problems arrive in the same place.

Winter air on the valley floor

Cold air pools downtown for days at a stretch in midwinter. Under that lid the pressure difference driving a flue weakens, fires burn cooler than they should, and a cool fire lays down deposit far faster than a hot one. A fireplace that pulled cleanly in October can be sooting and spilling by January with nothing about it having changed except the weather above the roof.

None of this is a reason to stop using an old fireplace. It is a reason to know what is actually inside the flue before you light it, and to have that written down rather than guessed at.