Chimney Shroud or Chimney Cap: What a Shroud Is

Cap, Shroud and Chase Cover

Three metal parts sit at the top of a framed chimney chase, and they are easy to mix up. On a factory-built fireplace, the cap is not a separate accessory: it is the listed termination, part of the chimney system the fireplace was tested with. The Superior wood fireplace manual we read says its system must end in one of its listed round-top or chase-top terminations, and names them by model.

The chase cover is the flat metal pan that closes the top of the framed chase around the pipe. In the Superior instructions it is fabricated from 28 gauge galvanized steel with a hole and a 2 inch collar for the pipe, set on noncombustible spacers, with a note not to seal its ventilation openings. The shroud is the third piece: a decorative box, often with a sloped or pyramid top, that hides the round termination.

• Cap or termination: on the flue itself, part of the listed chimney system.
• Chase cover: the flat pan on top of the chase, under the termination.
• Shroud: a decorative housing over or around the termination.

What the Florida Code Says About Shrouds

Section R1004.1 of the 2023 Florida Building Code, Residential, requires factory-built fireplaces to be listed and labeled, tested to UL 127 and installed in accordance with their listing. Section R1004.3 then deals with shrouds directly: a decorative shroud may not be installed at the termination of a factory-built fireplace chimney unless it is listed and labeled for use with that specific fireplace system and installed per the manufacturer's instructions. Section R1005.2 says the same for factory-built chimneys.

The Superior manuals add their own line: if a decorative shroud is to be installed, contact the manufacturer for specifications. In the notices that maker prints for Canadian installs, it allows a shroud approved by a testing agency for that fireplace, or a locally made one only with the maker's own shroud leg spacer kit.

What a Shroud Can Do to the Termination

A termination is tested to draw smoke in open air. Box it in and the air around it changes. The Majestic MPL11 manual warns that a cap placed where wind creates turbulence or pressure can cause poor draft and smoke spillage, and that poor placement lets wind-blown rain into the chimney. The Superior manual suggests spacing separate terminations at least 24 inches apart so smoke from one does not spill into another. An untested shroud can do any of these to its own termination: hold smoke and heat around the cap, change the draft, or steer rain into the flue.

A listed shroud has been tested with the system, which is why the code accepts it and nothing else.

Checks on a Shroud

When we find a shroud on a factory-built chimney, these are the checks before anything is cleaned or replaced.

• A label or paperwork showing the shroud is listed for this fireplace model.
• The termination underneath is the maker's listed cap, not a substitute.
• Clearances and spacers between the shroud and the termination as the instructions require.
• Rust, loose fasteners or storm damage on the shroud and the chase cover below.
• Ventilation openings at the chase top left open, not caulked shut.

If Your Shroud Is Unlisted or Damaged

A homemade or unlisted shroud is not something to fix in place; it comes off, and the listed termination is checked and left in open air, or a listed shroud for that system goes on. A damaged listed shroud is replaced with the same listed part where the maker still supplies it. Either way, do the looking from the ground; a chase top is a roof job.

Our chimney chase cover crew handles the chase top, the termination and the shroud together, and our chimney repair work covers the chase walls below if water has got in.

A Local Crew for the Chase Top

Shrouds and chase tops are work for an experienced roof crew, and ours belongs to a local, family-run business that is Proudly American. Ask for a free inspection, and our Proudly American family crew will tell you whether your shroud is listed, what it is doing to the termination and what the fix involves, in a written estimate.