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We pride ourselves on the knowledge and experience we've gained helping our customers (since 1978!) This section of our website contains articles about our industry and some of the challenges we've overcome.
If you have a topic/question you'd like us to cover, please click here and let us know. — Jason Clough
Chimney Spalling: Why Bricks Crack, Flake and Fall Apart
If you've noticed pieces of brick lying on your roof, in your gutters, or on the ground around your chimney, your chimney is probably spalling. This is one of the most common types of chimney damage we see in northeast Kansas, and it almost always starts with water.
Brick or stone spalling occurs when water has soaked into the brick and then freezes. This freeze cycle causes the water to expand which breaks the brick or stone apart. Spalling is much more prevalent from the roof up because more freeze/thaw cycles happen above the roof away from the protection of the house itself. Once bricks have begun spalling the damage will get exponentially worse every winter because the spalled surface allows even more water intrusion.
Read more: Chimney Spalling: Why Bricks Crack, Flake and Fall Apart
Chimney Crown vs. Mortar Wash: Why Most Masonry Chimneys Eventually Leak
If your chimney is leaking, cracking, or losing bricks, the problem may not be the bricks at all—it may be the top of the chimney. Many masonry chimneys are built with a simple mortar wash instead of a properly constructed reinforced concrete crown. While a mortar wash costs less initially, it is one of the most common causes of water damage and deterioration that we see during chimney inspections.
Almost all masonry chimneys are built originally with a mortar wash, or splay, instead of a proper crown. An argument can be made that this is what causes most problems with masonry chimneys. A mortar wash is typically made of hand formed mortar with no reinforcement. There is usually no bond break between the wash and the brick chimney and no expansion joint between the wash and the flue tiles. Often, a mortar wash is supported by plywood or other combustibles and it is not unusual to find these combustibles burnt and laying on top of the smoke chamber.
Read more: Chimney Crown vs. Mortar Wash: Why Most Masonry Chimneys Eventually Leak
Full Coverage Chimney Caps: An Alternative to a Concrete Chimney Crown
Water is the number one enemy of a masonry chimney. If you can keep most of the rain off the chimney, you can dramatically slow deterioration caused by freeze-thaw cycles. While a properly built concrete crown is an excellent solution, it isn't the only one. A custom-built full coverage chimney cap can protect the entire top of the chimney while offering several additional benefits.
Just like a proper crown, the full coverage cap acts like an umbrella keeping a majority of rain off the chimney. With this cap installed, wind-blown rain will still land on the windward side of the chimney but the rest of it will usually remain dry. Without it, the entire chimney will be wet every time it rains.
Read more: Full Coverage Chimney Caps: An Alternative to a Concrete Chimney Crown
Required chimney inspections
The chimney industry must adhere to national guidelines such as NFPA 211 and NFPA 54, alongside local building codes usually based on the International Residential Code. These standards dictate different levels of chimney inspections and specify when each level is necessary.
Wood stove evolution
Over the past fifty years, wood stoves and wood inserts have undergone significant transformations, particularly in the pursuit of enhanced efficiency. The 1970s marked the introduction of the "air tight" wood stove, a design shift focusing on controlling combustion air intake instead of using a damper in the stove pipe to regulate exhaust.
Tightly sealed homes and fireplaces
Open fireplaces and wood stoves depend on a good supply of air to function well. In homes that are tightly sealed to keep heat from escaping, this can also block the flow of necessary air for these fireplaces and stoves. This lack of air leads to issues like smoke from the fireplace filling the home, or wood stoves not burning efficiently. Such problems result in more creosote build-up, increasing the risk of chimney fires and lowering the quality of the air inside the house.
Purchasing the right firewood
Selecting the right firewood is crucial for optimal use of your wood stove or fireplace. It's essential that the firewood is dry, ideally with a moisture content below 20%. You can easily measure this using a moisture meter, which is readily available at most hardware stores or online for around $30. These meters have dual probes that need to be inserted into freshly split wood to gauge its internal moisture content accurately.