Riverton · Salt Lake County
Getting the Right Cap on a Riverton Chimney
The cap is the one chimney component people are most often sold the wrong version of, because on a factory-built system the cap is not an accessory. It is part of the appliance.
Two questions decide what belongs on top of your chimney: is the chimney masonry or a listed metal system, and does it vent solid fuel or gas. Get either wrong and the hardware is either useless or not permitted.
Listed chimneys take listed terminations
The metal chimney inside a framed chase was certified as an assembly, and the termination on top of it was part of what got tested. Swapping in a generic cap from a hardware store changes the airflow at the top of a system whose draft characteristics were established with the original in place, and it takes the installation outside its listing. When a termination on one of these has corroded or been damaged by wind, the replacement is the manufacturer's part for that system.
Masonry chimneys and what they need
On the brick stacks around the older Riverton properties, a stainless multi-flue or single-flue cap does three jobs at once: it keeps rain and snow melt off the smoke shelf and out of the damper, it stops birds nesting in an open flue, and on a solid-fuel chimney the mesh acts as a spark arrestor. It is one of the least expensive things on a chimney and it prevents several of the more expensive repairs.
Exposure out here
Chimneys on the open ground at this end of the valley get more wind than sheltered ones, and wind matters at the top of a flue in two ways. It drives rain against and into an unprotected opening, and on some roof geometries it presses down the flue and stalls the draft. A cap that is properly secured and, where needed, shaped to break that pressure is worth having on an exposed lot. Anything only friction-fitted onto a flue tile will eventually be somewhere else.
Dampers and dry flues
Open masonry fireplaces lose heated air continuously through a throat damper that no longer seals. A top-mounted damper with a gasket closes the flue at the top instead, which also keeps the whole chimney dry all summer and stops the musty smell that comes with a damp flue.
Waterproofing masonry
Repairs first, sealer second, and the sealer has to be vapor permeable. Brick needs to dry outward, and a film-forming coating traps water in the wall where the next freeze can break it apart. A siloxane repellent stops liquid water entering while letting vapor escape, which is the combination that actually protects masonry here.
Questions
Caps & Dampers in Riverton — common questions
Can I buy a cap at a hardware store and fit it myself?
On a masonry flue, a properly sized stainless cap secured to the tile is a reasonable job if you are safe on a roof. On a factory-built metal chimney, no. That termination is part of a listed assembly and it needs the manufacturer's matching part.
Does a gas fireplace chimney need a cap too?
It needs the correct termination for the appliance, which for a direct-vent unit is the sealed coaxial terminal supplied with it. Do not add mesh, screening or an aftermarket cover to a gas termination, because restricting it interferes with the balance the appliance depends on.
How should a cap be fixed down on an exposed lot like ours?
Mechanically, not by friction. A cap that simply slips over a flue tile relies on being a tight fit, and out here that eventually loses. We want a clamped or fastened attachment on masonry, and on a listed metal chimney the manufacturer's own termination, secured the way its instructions specify.
Will waterproofing stop our chimney leaking?
Only if the leak is water soaking through sound brick, which is one cause among several. If the crown is cracked, the joints are open or the flashing has failed, a sealer will not solve it and can make matters worse by trapping water. We repair first and seal afterward.
Also in Riverton
Our other services here
Chimney Sweep Inspection Chimney Repair Fireplace Repair Installation Gas Fireplace Dryer Vents All Riverton services
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