How Do Freezing Temperatures Damage My Chimney?
You may have heard about how very cold air temperatures can cause damage to the masonry of a chimney. Actually, it’s not the temperature as much as the way water from rain and melting snow reacts in freezing weather. Here’s what we mean.
The freeze-thaw cycle
Bricks are porous and absorb water. Water also can seep into small cracks in a chimney’s mortar that were caused by the normal settling of the house, weather events or plain old age. When this water freezes, it expands and puts pressure against anything surrounding it. Repeated freeze-thaw cycles will begin to cause deterioration in a chimney’s bricks and mortar.
Early signs of chimney damage include:
- Crumbling in sections of the chimney’s masonry
- Cracks in the chimney crown or mortar joints
- Loose or missing bricks
If initial damage isn’t addressed and fixed, deterioration can allow water to infiltrate the chimney system. Signals that this is happening include:
- Foul odors coming from the fireplace due to excess dampness in the flue
- Broken flue tile pieces in the firebox
- Staining on the home’s interior walls or ceiling area near the fireplace
- Efflorescence (white powdery substance) on the chimney’s exterior
- Water in the firebox
- Addressing chimney water damage
If you know or believe that your chimney is damaged, call a professional. If the damage is in early stages, a waterproof sealant often can prevent further damage by keeping water out.
If sections of brick and mortar are crumbling, a process called tuckpointing may be used to fill in open areas with new mortar and restore strength to the chimney structure.
In cases of severe damage – such as when large areas of the masonry are crumbling or the chimney has begun to lean to one side – a full or partial rebuild may be required.
Annual chimney inspections
It’s a smart move to schedule annual chimney inspections with a certified chimney services company whose technicians have the equipment and hands-on experience to deal with all types and levels of chimney damage. A professional can spot initial damage before it turns into an expensive or dangerous problem and them set about performing the necessary repairs.
Remember – it’s not just masonry issues that can lead to water damage. A faulty or missing chimney cap and warped or corroded flashing around the base of the chimney where it meets the roof will allow water to get into the chimney or run down the outside of it into the house. Chimney service techs will inspect every area of your chimney to ensure everything is in proper working order.
For homes with wood-burning fireplaces, an annual inspection should include a thorough cleaning to remove flammable creosote from the chimney flue. Creosote buildup can cause drafting problems and lead to a chimney fire.
Northeastern Chimney of West Hartford, CT, is ready to help with all manner of chimney inspections, cleaning, repair and rebuilding. Our goal is the same as yours: a fireplace and chimney that work efficiently and safely. If you’d like to know more about our services or schedule an appointment, call (860) 233-5770.