Chimney crown, chase cover, chimney cap: What’s the difference?


Three of the most common, and the most commonly confused, words when discussing chimneys are chimney crown, chase cover and chimney cap. Often these words are used interchangeably, but in fact, they represent very different components that sit atop chimneys. It’s important to know the difference so you can communicate effectively with your chimney sweep — It’s difficult to describe or understand a problem if you’re unsure what the terms are referring to!

Chimney crownDifference between Chimney crown, chase cover, & caps - New Haven - Fairfield CT - Total Chimney Care

Chimney crowns are a masonry component at the very top of a chimney’s structure. Made of concrete, the chimney crown seals the top edge of your chimney. It slopes away from the chimney flue to help divert water downward, and it should extend a few inches beyond the edges of the chimney itself to help shield the chimney structure from water.

Too often, chimney crowns are improperly constructed from masonry mortar, which leads them to crack and wear away quickly. Even properly constructed chimney crowns will crack or deteriorate over time. A crack in your chimney crown can lead to water damage, so it’s important to be aware of its condition. Your chimney sweep should update you on the health of your chimney crown during your annual inspection.

Chase cover

A chase cover offers a similar function to a chimney crown, but it is made from metal and sits atop factory-built chimneys. Chase covers are used on non-masonry chimneys, such as vinyl, wood, or aluminum sided chimneys. Like chimney crowns, they seal around the edges of the chimney to help keep water away from the flue.

Even though chase covers are made from metal, they are break down over time. The metal corrodes, and can lead to rust dripping down the sides of your chimney or water leaking down the inside of your flue. Every so often, your chimney chase cover will need to be replaced. As with a chimney crown, your sweep should give you an idea of the condition of your chase cover during your annual inspection.

Chimney cap

A chimney cap works in conjunction with your chase cover or chimney crown to keep water from penetrating your chimney. A chimney cap fits atop the opening of your flue to keep rainwater, snow or ice from flowing freely down the walls of your chimney. Most chimney caps are elevated from the main chimney by a wire cage. This case allows smoke to exit your chimney while keeping birds, rodents and debris from entering your chimney.

Chimney caps, too, are subject to break down or become displaced over time. You’ll want to make sure your chimney sweep reports on the health of your chimney cap, as it’s your chimney’s primary defense against water damage.

Chimney crown, chase covers and chimney caps are the most crucial elements to protect your chimney and your home from water damage. Be sure you know the health of your chimney crown or chase cover and your chimney cap, and make sure you communicate with your sweep to know when a repair or a replacement is needed!

If you have questions about your chimney crown, chase cover or chimney cap, call the experts at Total Chimney Care at 203-874-6772.