When it comes to chimney maintenance, most homeowners remember to clean out their fireboxes and know they need to have their chimneys swept. However, many may forget that some of the most important parts of the chimney cannot be seen from street level. One of these chimney parts that is often ignored is the chimney crown.
What is the chimney crown?
Chimney crowns are the slightly-angled slabs that surround and protect the top of the flue. Sometimes referred to as a chimney wash, the chimney crown acts as the base for the chimney cap; chimney crowns are designed to help moisture from ice, rain, or snow to flow away from the chimney structure and safely onto the roof.
What causes chimney crown damage?
There are a number of factors that can cause chimney crown damage. One of the primary causes of chimney crown damage is improper construction. Oftentimes, inexperienced contractors build the chimney crown using mortar instead of cement. Mortar, however, deteriorates much faster than concrete, especially when constantly exposed to the elements. The can cause the chimney crown to crack and spall, allowing moisture into the chimney structure.
Another major cause of chimney crown damage is long-term exposure to the elements without upkeep. Because of their location, chimney crowns take the brunt of Mother Nature’s forces; they are constantly exposed to varying temperatures as well as large amounts of moisture. These conditions can take a toll on chimney crowns, especially if it is not correctly angled. If left too flat, water and moisture can accumulate on the chimney crown and cause further damage.
Chimney crowns may also lose their watertight seal around the flue. This happens due to long term extreme temperature variations caused by fireplace use. The hot air and gas from a fire as it travels up the flue along with the cold outside air temperatures can cause the chimney crown to expand and contract, breaking the seal. This can let water into the chimney, causing even faster deterioration.
Chimney crown repairs
If your chimney is leaking, your chimney crown may be to blame. In these cases, we often recommended either repairing or rebuilding the chimney crown. The amount of repair needed will depend on the amount of damage the chimney crown has suffered.
When building or repairing a chimney crown, one of the keys is to make sure the edges extend over the sides of the chimney structure. This lip is known as a kerf and should extend at least 2-2.5 inches beyond the sides of the chimney. This acts as a rain gutter that helps water flow away from the chimney and onto the roof.
If your chimney crown only needs minor repairs, we often recommend CrownCoat, a professional waterproofing sealant that can help protect and extend the life of your chimney crown. When applied professionally, CrownCoat comes with a 15 year warranty, giving you peace of mind that this eco-friendly product will last.
Whether your chimney crown has minor damage or needs to be complete rebuilt, trust the experts at Lords Chimney to repair your chimney crown.
Is your chimney leaking? We’re willing to bet that if you’ve found this blog post, you may be trying to find an answer to why there are water stains on the ceilings or walls around your chimney or why you smell mold or hear a drip-drip-drip sound coming from your chimney. A chimney leak can be caused by any number of things, but here in Houston, Lords Chimney’s certified technicians have seen it all; from our many years of leak resolution, we now know that most chimney leaks can be attributed to one of the following four issues:
All chimneys—whether they’re brick, stone, or prefab—require some type of maintenance to keep water out of them. We’re happy to advise you about which waterproofing method(s) are best for you and your home.
1. Gapping or Rusted Flashing: Flashing is the metal band that is woven around the base of your chimney where it meets your roof. In most cases it is partially embedded in your roof’s shingles—so that new flashing is often installed at the same time as a new roof. This junction point is a vulnerable one, hence the flashing is installed to give it added armor from potential leaks. However, flashing is notorious for gapping or rusting over time, especially if caulk has come loose or if the flashing was installed improperly. If we determine that faulty flashing is the cause of your leak, Lords Chimney can either repair your existing flashing or custom fit new flashing onto your chimney.
2. Inadequate Protection Up Top: A chimney without a chimney cap or a top-sealing damper is not unlike a house without a roof. In other words you’ve got a recipe for disaster, as your chimney is inviting water into your home. A chimney cap or top-sealing damper will not only keep water out but also keep animals and debris out, keep sparks in, and in the case of a chimney damper, save you money on energy bills.
3. Cracked Crown: At the very top of your chimney sits your chimney’s crown, which seals your chimney from the chimney’s flu(es) to the edge of the chimney. According to the CSIA, “The crown should provide a downward slope that will direct the water from the flue to the edge of the crown. The overhanging drip edge, by directing the run-off from the crown away from the chimney, helps prevent erosion of the brick and mortar in the chimney’s vertical surfaces.” Many chimney crowns are built with an inadequate mortar mix that too soon chips or cracks, allowing water to seep in. In many cases existing crowns can be repaired, though we sometimes determine that a crown needs to be completely rebuilt.
4. Masonry Problems: Surprisingly porous, brick and mortar—if not professionally waterproofed and maintained—can actually act as a sponge to draw water into your chimney. In addition, chimney brick can crack and spall over time, making your chimney more susceptible to leaks. If this is the case, tuckpointing or other repairs may be necessary, along with the application of a waterproofing sealant.
Lords Chimney serves the entire Greater Houston area. Having chimney problems? We hope you will call us first.
Has the inside condition of your chimney ever concerned you? Are you confident enough to say that after years of successive use and all the times your chimney never let you down, that it’s still in perfect condition? It is important for your home, your family and your bottom line, to keep your chimney cleaned and inspected annually. Knowing the basics can help you understand and make more informed decisions about your home.
Getting to Know the Parts
Learning about how your chimney works makes the annual conversation with your chimney sweep a great deal more clear. You need to understand to make the best decisions with regard to risk.
It is important to know the parts of the chimney. You should at least know which is which and which goes where. There are six important parts to remember that overall, help the function of the chimney.
At the uppermost part of the chimney is the spark arrestor. This performs the duty of preventing sparks from getting out of the chimney. You might think that this part is somehow unimportant but we all know that fire can spontaneously and unexpectedly start with a single spark along with the wind’s aid. It can automatically turn into a blazing roof fire. This is exactly why this part is very important.
Below the spark arrestor is the chimney crown. This functions as a shield and a barrier for any object and huge volumes of water to enter and accumulate inside the chimney.
The flue is another vital part of the chimney. It is long and thin and is often mistaken to be the chimney. This should always have a flue liner attached to it for two reasons:
Protection of the flue itself
Helping hand to the performance of the chimney as a whole
At the very end of the flue is the damper. This opens and closes the flue. Always make sure that when you are lighting up your fireplace, the damper should always be open. When you see abundant smoke coming out of your chimney, this means that the damper is closed. It’s important to check before attempting to ignite a fire in the fireplace.
Below the damper is the smoke shelf. This performs the duty of catching any foreign and unwanted objects that passes through the chimney. This might cause serious problems when involved in the fire.
Lastly, the smoke chamber is one of the most important parts of a chimney. I’m sure you’re already wondering why. This performs the most important task and that is to compress gases during combustion. If this has a defect, the smoke will go into your home instead of going into the chimney flue. This may cause negative air pressure and carbon monoxide to fill your home’s atmosphere.
The Importance of Knowing
You see, chimneys can be very tricky. They might always seem okay on the outside but big problems may start to rise on the inside. Eventually, you might need to get your chimney relined and restored to ensure safe and stable performance all throughout the winter season.
Here at Lords Chimney, we want to make sure you are aware of the fundamental parts and functions of your chimney. This can be beneficial on your part as a homeowner because you are allowing yourself to be completely aware of the things that are really important concerning your chimney. This can help us talk to you about your chimneys’ condition easily and effectively.