Everything You Need to Know about Chimney Caps

A man installing a single-flue stainless steel chimney cap on a multi-flue chimney

Between pricing, sizes, and installation, there’s a lot to understand about chimney caps. These humble metal shields have a lot going on under the hood, and it can be tough to know just where to start.

At HY-C, we’ve been manufacturing chimney caps for over 75 years. We’ve produced millions of them during that time, and we want to share everything you need to know about chimney caps with you to make sure you get the perfect one for your home.

In this guide, we’re going to cover what chimney caps are, how they work, and if you even need one at all. We’ll also take a look at how much a chimney cap costs, what sizes they come in, and how to install them.

By the time you’re finished here, you’ll be armed with all the information you need to ensure you purchase the perfect chimney cap for your flue.

What is a Chimney Cap?

A basic chimney cap consists of three main components:

  1. A solid metal band (or base) at the bottom
  2. A metal mesh body
  3. A metal hood welded on top

Found most commonly on wood burning fireplace chimneys, chimney caps are installed on top of your chimney flue or crown. They serve two primary purposes:

  1. Keeping rain, sleet, and snow out of your chimney and firebox
  2. Keeping animals (like raccoons and birds) out of your chimney

Chimney caps can be made of a few different kinds of metal, but by far the most common are:

  1. Galvanized steel
  2. Stainless steel
  3. Aluminum
  4. Copper

Do You Need a Chimney Cap?

This may sound biased coming from a chimney cap manufacturer, but if you have a wood burning fireplace, the answer is yesyou should have a cap on your chimney.

Leaving your chimney uncapped is like leaving a door or window open — not only will rain or snow accumulate in your fireplace, but you’ll also invite a host of animals and insects directly into your home.

Chimney caps are also vital while you’re burning wood in your fireplace. They can prevent downdrafts from the outside into your chimney flue, ensuring smoke and other gasses don’t spill back out into your home.

Should an Unused Chimney be Capped?

You might be wondering, “Even if I don’t use my fireplace, do I still need to put a cap on my chimney?” It’s a fair question. But even if you don’t use your fireplace, you should still put a chimney cap on your flue or crown.

Weather and wildlife can still get in, even if you never use your fireplace. A small $60 to $100 investment in a chimney cap can save you thousands of dollars in damage caused by a bird, raccoon, or bat later on.

What are the Disadvantages of a Chimney Cap?

A good, solid chimney cap will do its job well for years at a time. But there are some caveats to chimney caps that you should consider before you get one.

Chimney caps are usually installed at the highest point on your home, so it can be tough to get to them to inspect for damage. It’s wise to examine your cap every few years to make sure it’s still on tight and not deteriorating, but some caps are hard to access.

Also, depending on which type of metal your cap is made from, it may rust after a while. A rusty cap will wind up with holes that animals can bypass or rain can fall through.

What Does a Chimney Cap Sit On?

Chimney caps go on chimneys, of course. But, more specifically, what does the cap itself actually attach to?

That depends on whether you have a single-flue chimney cap or a multi-flue chimney cap. A single-flue chimney cap is just what it sounds like — it covers just one flue pipe. As a result, the majority of single-flue chimney caps attach directly to the chimney flue tile.

A black galvanized single-flue chimney cap being in stalled in a chimney flue with trees in the background
A single-flue chimney cap being installed on a flue

A multi-flue chimney cap, on the other hand, covers two or more flue pipes that protrude from the chimney’s crown. The crown is the concrete cover that seals the top of the chimney, and a multi-flue cap is screwed directly into the crown (as opposed to attaching to a flue).

A stainless steel multi-flue chimney cap being installed on a chimney flue with trees in the background
A multi-flue chimney cap resting on a chimney crown

How Much is a Chimney Cap?

The price of a chimney cap can vary quite a bit, and our chimney cap cost guide has more specific, in-depth information on the topic. Generally speaking, though, chimney cap cost is determined by two factors: material and size.

GalvanizedStainlessCopper
9” x 9”$56$79$376
9” x 13”$60$92$398
13” x 13”$67$99$422
13” x 18”$74$125$446

The table above outlines the cost of a few different chimney cap sizes based on the material from which they’re made. A bigger cap utilizes more material and therefore costs more.

When it comes to metals, galvanized steel is a budget-friendly, economical material, while stainless steel costs a bit more but holds up longer.

Copper is a premium material, and chimney caps made out of copper command a pretty penny (pun intended).

Do Chimney Caps Come in Standard Sizes?

This is a complicated question. Essentially, yes — there are four chimney cap sizes that can basically accommodate around 90% to 95% of the chimneys out there:

  • 13” x 13”
  • 9” x 9”
  • 9” x 13”
  • 13” x 18”

And while those sizes will take care of most flues, there are several factors to consider, including:

  • Whether you need a single-flue or multi-flue cap
  • The shape of your flue tile (round, square, or rectangular)
  • The height of your flue tile (from the chimney crown)
  • Whether you need ⅝” mesh (as a California or Oregon resident)

Chimney cap sizes are a complex topic, and our chimney cap size guide takes a much deeper dive into dimensions and cap types to help you find the perfect size for your chimney flue or crown.

Who Installs Chimney Caps?

A roofer placing a black galvanized multi-flue chimney cap on top of a chimney crown on a roof with trees in the background

Chimney caps are most commonly installed by two kinds of professionals: chimney sweeps and roofers. Both groups are familiar with the safety procedures involved with working from heights, and they’re typically well-versed in chimney cap sizes and styles to help you find what you need.

Can You Install a Chimney Cap Yourself?

If you can assemble your own furniture, you can probably install your own chimney cap. Both require the same entry-level familiarity with tools and hardware. The primary difference, though, is that installing a chimney cap requires venturing onto your roof.

As a chimney cap manufacturer, we’d recommend against climbing your roof to install a cap yourself. Climbing a roof is dangerous, and falling can result in severe injuries. Leave your cap installation to a chimney sweep or a roofer who has experience with working from heights.

How Long Do Chimney Caps Last?

When they’re installed properly, a galvanized steel, stainless steel, or aluminum chimney cap can last for 50 years or more.

A well-installed metal chimney cap locks wildlife out very well, and they typically can’t bypass them, even with a lot of effort. The greatest danger to a chimney cap is gale-force winds, particularly from hurricanes.

If, by chance, a strong storm does somehow manage to blow your cap off, we’d recommend replacing the entire chimney cap — not reinstalling the damaged one.

Which Chimney Cap Should You Get?

If you’ve read this entire guide so far, you’ve read over 1,100 words on chimney caps — everything from what they are, to what they’re made of, to how to install them. Hopefully, at this point, you have a clearer picture of what kind of cap you might need for yourself.

From here, one of the biggest battles is figuring out what size you need. Chimney caps are like shoes: if you don’t get the right size, the cap simply won’t work out for you.

Our chimney cap size guide covers every possible size you’ll need for single-flue, multi-flue, and band-around-brick chimney caps. It will help you find the perfect cap for your chimney so you can keep your fireplace weather- and wildlife-free.

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