Do You Have the Right Chimney Crown?

Not sure what a chimney crown is or why it's important? Learn why below!

Not sure what a chimney crown is or why it’s important? Learn why below!

In the past, we have had customers come to us to fix what other companies have previously repaired. Not only does this cost them far more money in the long run, but it also typically means their chimney has been further damaged. When it comes to chimney repairs, the lowest bid does not always equal the best service.

What are chimney crowns?

A chimney crown, sometimes known as a chimney wash, is the slab that covers the top of the chimney structure. Chimney crowns are important because they protect both the interior and exterior chimney structure from the elements. An improperly installed or damaged chimney crown can expose the interior of the chimney and fireplace to rain, snow, and other moisture while simultaneously exposing the brick and mortar of the chimney itself.

What to look for in a chimney crown

Although they can be difficult to inspect from the ground, there are several hallmarks of good chimney crowns that homeowners should be aware of. The first is the overhang, or drip ledge. To prevent water from flowing directly onto the masonry of the chimney structure, chimney crowns should have a drip ledge of at least 2 to 2.5 inches on all sides. These overhangs serve as miniature gutters, protecting the brickwork and mortar from direct exposure to rain and snow.

Another detail to look for is the material the chimney crown is made of. While regular masons may be qualified to lay bricks and mortar for a chimney, the same materials should never be used for the chimney crown itself. Because brickwork and mortar are porous materials, they should never be used to construct a chimney crown. If your chimney crown is made of mortar, it will quickly crack and deteriorate due to exposure to the elements. Instead, crowns should always be constructed from solid metal, stone, or concrete slabs.

Chimney crown supporting structures

While not technically part of a chimney crown, chimney flashing is an important structural element that also helps prevent moisture from entering a chimney structure. Even with a properly sized overhang, flashing is an additional layer of protection against the elements. Often made of metals such as aluminum, galvanized steel, or copper, flashing is designed to create a waterproof seal between the chimney and the roof itself.

However, flashing is often improperly installed which may cause the waterproof seal to be broken. Roofers often use too many nail holes, creating tiny crevices from rain and snow to gain access to the brick and mortar underneath. Likewise, over time the flashing may become loose or damaged, especially in areas prone to severe weather.

At Jack Pixley Sweeps, we can do more than just clean and inspect your fireplace. Our masons are specially trained to craft chimney crowns that are constructed with extreme attention to detail. While our services may not always be the least expensive, our chimney crowns are guaranteed to protect your chimney and last for years to come.

Anatomy of a Chimney

Understanding the Anatomy of Your Chimney

Many people have fireplaces and chimneys in their homes and trust that they will always work as they are supposed to. However, there are many ways that a chimney could malfunction and it is important to understand exactly how this occurs. In order to maintain a safe chimney, homeowners should be familiar with the parts of their chimney and how they function. This will help them to quickly identify any issues that may arise and help you communicate with a certified professional.

At the very top of the chimney, there is a piece called a spark arrestor. This will keep sparks from leaving the chimney. A small spark may not seem like a big deal but, with the proper wind, a hot spark can quickly turn into a big fire. If this occurs on the roof, the fire will spread not only throughout the home, but it could also quickly jump to the neighbor’s home. Even very warm ash leaving the chimney can start a fire in this way, making the spark arrestor a vital piece of chimney safety.

Photo of Single Flame

It only takes a spark.

Also at the top of the chimney is a cement piece known as the chimney crown. This protects the upper layer of bricks on the chimney. More importantly, it helps keep foreign material out of the chimney. In addition to many other substances, it keeps excess moisture from entering the chimney, which can cause a great deal of structural damage. In addition to the chimney crown, many people also choose to use a separate chimney cap.

The long part of the chimney, which allows smoke out of the fireplace, is known as the flue. Inside of the flue is a long piece called the flue liner. This liner helps protect the flue from general wear and tear as well as damage from water. Liners come in a variety of materials, including clay, tile, and stainless steel. However, stainless steel is typically considered the best choice because it is the most durable and lasts the longest.

Inside of the chimney is a piece called the damper. The damper opens and closes the flue, either letting smoke out or trapping it in. It is very important to make sure that the damper is always open when burning a fire in the fireplace. Leaving it closed will quickly fill the entire home with smoke and dangerous gas.

Also inside of the chimney is a smoke shelf. This is a small piece that catches material falling through the chimney. This could be anything from ash to debris from animal nests inside of the chimney. If these materials find their way into the fireplace, they could start a dangerous blaze that quickly gets out of control. It is very important to make sure that the flue is always clear of all debris, but the smoke shelf provides extra protection in the event that anything does make its way in there.

When material burns in the fireplace, it creates combustible gas. The smoke chamber compresses the gas so that it does not create a back draft. Without it, the gas may enter the fireplace or the home, causing both health and safety risks for the entire household.

There are many different parts to a chimney and each plays and important role in the safe use of the fireplace. In order to use the chimney and fireplace without incident, homeowners should understand exactly how each piece works and what it does. This will make it possible for them to quickly identify any problems and decide what action needs to be taken before using the chimney again.