This is your reminder to check on your chimney and look out for the four most common chimney issues – it might save the lives of you and your family! The most common chimney issue is creosote buildup, and if you are not sure what creosote is, read more about it here and learn ways to avoid having it build up in your chimney and fireplace. Other common chimney issues include additional problem areas, damages, and obstructions.
Common Chimney Issues 1: Obstructions
A partially or fully blocked chimney can be extremely dangerous, and different things can obstruct your chimney. The most common obstructions include:
- Creosote Build-Up: Creosote is a byproduct of burning wood or fossil fuels in a fireplace or stove, and is the singlemost common chimney issue. Over time, creosote can accumulate on the inner walls of the chimney, forming a thick, flammable layer. If left unchecked, creosote buildup can obstruct the chimney, reduce airflow, and increase the risk of chimney fires.
- Animal Nests: Birds, squirrels, raccoons, and other animals may build nests inside chimneys, especially during the warmer months when the chimney is not in use. These nests can block the flue, preventing proper ventilation and causing smoke and carbon monoxide to back up into the home. Additionally, nesting materials are highly flammable and can ignite, leading to chimney fires.
- Debris : Leaves, branches, twigs, and other debris can accumulate on the chimney cap or inside the flue opening, obstructing airflow and trapping combustion byproducts. Additionally, objects such as balls, toys, or even branches blown onto the roof can accidentally fall into the chimney and create blockages.
- Structural Damage: Crumbling masonry, loose bricks or mortar, collapsed flue tiles, or displaced chimney liners can create obstructions within the chimney. These structural issues not only impede proper ventilation but also compromise the chimney’s stability and integrity.
- Soot and Ash: Excessive soot and ash buildup can narrow the flue passage, hindering the escape of smoke and gases. If not cleaned regularly, these residues can solidify and form blockages, leading to poor chimney performance and potential hazards.
- Faulty Dampers: Dampers control the airflow in the chimney, allowing smoke to exit while preventing downdrafts and reducing heat loss when the fireplace is not in use. If a damper becomes stuck or malfunctions, it can obstruct the flue opening, resulting in poor ventilation and smoke backup.
- External Factors: Environmental factors such as ice, snow, or frost accumulation, particularly in colder climates, can obstruct the chimney’s exterior venting system. Additionally, overhanging tree branches or nearby foliage can block the chimney cap or flue opening, restricting airflow and increasing the risk of chimney obstructions.
Blockages in your chimney create operating problems with your fireplace or stove and can cause carbon monoxide fumes to enter your home. In addition to those fumes, a blocked chimney can cause your house to catch fire! If you suspect possible chimney obstructions, a quick and safe way to spot them is to keep an eye on any possible smoke or soot entering the home when you burn a fire in the fireplace. Remember that obstructions are not always visible, and the best prevention for chimney obstructions is to have your chimney professionally cleaned at least once a year.
Common Chimney Issues 2: Damaged Liner
The chimney flue liner is arguably the most important part of your chimney. It protects the most flammable parts of the chimney from the heat. It is common for chimney liners not to last quite as long as the rest of the chimney. Creosote and other obstructions build up over time and can cause damage to the liner if left untreated. As with other issues, chimney liner deterioration can cause your home to be vulnerable to fires. Here are some common chimney issues that cause liner damage
- Creosote Build-Up: Our old enemy, creosote, can accumulate on the interior walls of chimney liners. This sticky, tar-like substance not only increases the risk of chimney fires but also accelerates liner deterioration by promoting corrosion and chemical degradation.
- Heat and Thermal Stress: Of course heat is a common chimney issue, since that’s what your fireplace is made for! Continuous exposure to high temperatures from burning fires can cause chimney liners to expand and contract. This thermal stress weakens the liner material over time, leading to cracks, fissures, or warping. Inadequate insulation or oversized fires can exacerbate this issue by subjecting the liner to extreme temperature fluctuations.
- Corrosive Flue Gases: Combustion byproducts such as moisture, acids, and corrosive gases emitted during the burning process can corrode chimney liners, especially if the liner material is not resistant to acidic substances. Acidic condensation can eat away at the liner surface, causing it to deteriorate and lose its structural integrity over time.
- Water Damage: Moisture intrusion is one of the primary causes of chimney liner deterioration. Water can enter the chimney system through gaps, cracks, or damaged mortar joints, especially in masonry chimneys. Once inside, water can degrade the liner material, weaken its structural integrity, and cause it to crack or crumble over time. Freeze-thaw cycles further exacerbate this damage by causing expansion and contraction of water trapped within the liner.
- Age and Wear: Like any building component, chimney liners have a finite lifespan and will degrade over time with regular use and exposure to the elements. Older chimney liners made from clay tile, cast-in-place concrete, or metal may deteriorate due to age-related factors such as material fatigue, corrosion, or natural wear and tear.
- Poor Installation or Maintenance: Improper installation, substandard materials, or lack of regular maintenance can accelerate chimney liner deterioration. Poorly fitted liners may be more prone to cracking or shifting under thermal stress, while neglecting routine cleaning and inspection allows creosote buildup and other issues to go unnoticed and worsen over time.
Common Chimney Issues 3: Crown Damages
Your chimney crown is at the top of your chimney. It creates a seal around the perimeter of your chimney by connecting the outer edge of the chimney to the inner edge of the flue liner. Chimney crowns are made from a unique mortar mix that, while secure, is subject to cracking and chipping over time. Moisture easily enters through the damaged areas of the crown and causes extensive corrosion. If you are able to catch the damage early, it is simple to repair damages to your chimney crown. It is ideal to identify damages early on to avoid complete chimney replacement. Waterproofing your chimney crown is a great way to help prevent damage and corrosion.
Common Chimney Issues 4: Leaking Flashing
Installing chimney flashing is a difficult task to begin with because creating a watertight seal is challenging. It is extremely important to have professionals install and repair your chimney flashing to avoid any issues during install and repairs. It is easy for water to enter damaged flashing and spread to the unprotected part of your roof, causing additional damage. People often do not discover leaking flashing until they see interior roof leaks, and by then, it is often too late to prevent extensive damage to the ceiling or even structural damage. Repairing damages from leaking flashing can become expensive. It is easy to do a visual check of your chimney and attic area to help prevent leaking flashing.
If you think you have identified any of these issues with your chimney, or if you just want to avoid them in the future, give us a call to schedule your cleaning.