Protecting your chimney from water penetration is one of the most important maintenance responsibilities of a homeowner. Water leaks can cause a lot of expensive and extensive damage to a masonry chimney, which is why the Chimney Safety Institute of America (CSIA) has called water the biggest enemy of masonry chimneys.
While chimney leaks can originate anywhere, we see two common areas:
- A cracked masonry crown
- Around the chimney flashing
Water can be very tough on masonry materials, like the bricks and mortar of your chimney. Since these materials are naturally porous, they absorb water from rain, ice, and snow. During the winter, any water trapped inside the masonry materials will freeze and expand whenever the temperature falls below 32 degrees Fahrenheit. When the weather warms up, this water thaws, and its force can cause the bricks and mortar to crack and break apart. Repeated freeze/thaw cycles can lead to severe structural damage, including the collapse of your chimney. Other types of damage that we have seen from chimney water leaks includes rusted metal chimney components, rotted adjacent wood, and stained ceilings and walls.
Chimney flashing maintenance is of equal importance. A flashing system consists of metal sheets that are wrapped around the chimney where it meets the roof. This intersection of the chimney and the roof is one of the most vulnerable areas for water leaks because water from rain and melted ice and snow tends to pool in this area. You need a good flashing system to provide a watertight seal of your chimney. Below are some common reasons flashing may need to be replaced:
- The flashing is missing because of erosion or the long-term effects of weather may have worn it away.
- You’re having shingles on your roof replaced.
- The flashing is rusted – most flashing is made of aluminum or copper, which do not rust. Some older chimneys are flashed with galvanized metals, which will rust over time.
- The flashing has been covered up with roofing tar, diminishing its effectiveness.
- Your home has settled or shifted – most chimneys aren’t attached to the frame of your house – which opens the door for leaks.
Before the freezing weather sets in, contact a roofing professional like Solid Rock Roofing and ask about a winter check-up to ensure your chimney has all the proper flashing parts. An ounce of prevention is worth a pound of cure when it comes to keeping your home free of water damage.