Common Causes for Chimney Leaks & How To Fix Them
A chimney leak can create structural damage and cause mold to form within your home. There are a handful of reasons why your chimney may be leaking, so narrowing down the cause is easy. The Mad Hatter can inspect your chimney and perform all recommended fixes if you suspect that you have a chimney leak.
Signs That Your Chimney Is Leaking
Here are some signs that you may have a chimney leak.
- Water or condensation in the fireplace
- Musty odors coming from the chimney or fireplace, especially after it rains
- Water stains on the walls or ceiling near your chimney
- You can hear water dripping or can see water forming
- Exterior or interior masonry is cracked
- External masonry is a white discoloration
- Rust on the damper or other metal areas within the fireplace
If you notice any of the signs above, contact The Mad Hatter for a NCSG-certified chimney sweep® and inspection to confirm whether or not your chimney is leaking.
Common Causes of Chimney Leaks and How To Fix Them
If you are wondering why your chimney is leaking, you can use this list to help you figure out the cause of your chimney leak.
Rain Entering From The Top Of The Chimney
This is the simplest and most common reason you may have a leaking chimney. If your chimney does not have a protective cap or rain pan installed, rain will fall straight down into your chimney. Allowing rain to fall directly into your chimney will cause a leak to form over time.
How To Fix: The Mad Hatter can install a custom chimney cap or rain pan to protect your chimney from the elements. Not only will a chimney cover work to keep the rain out, but it will also protect your chimney from animals and other debris. Keeping animals and debris out of your chimney will help reduce your chance of a chimney fire.
Your Chimney Crown Is Cracked
The chimney crown refers to the cement slab at the top of your chimney and is different from the chimney cap. A chimney cap is metal and covers the opening of the chimney. A chimney crown is cement and covers the entire top of the chimney with the purpose of protecting the external chimney bricks from water damage.
If your chimney crown is cracked, water will go straight through those cracks and hit the external bricks on your chimney. Brick and mortar are not waterproof, which is how a cracked chimney crown can cause water damage and leaks to form in your chimney.
How To Fix: Fixing a cracked chimney crown depends on the severity of the damage. Small cracks are common and should be fixed, as they can grow larger if left unfixed. The Mad Hatter can coat your chimney crown with special materials to help prevent small cracks from becoming a larger issue. However, if the damage is more significant, we will need to remove and relay the masonry of your chimney crown.
Leaks Caused From Chimney Flashing
There is a gap between the area where your chimney sticks out of the roof and the roof itself. Chimney flashing is made of aluminum and is designed to keep water from entering that area (it is the aluminum material at the base of the chimney in the photo above). The flashing is held in place and sealed with a tar-like substance. Chimney flashing and tar are waterproof but won’t last forever. The seal may crack and give over time, which can cause your chimney to leak.
How To Fix: During your annual inspection, a Mad Hatter technician will look at your chimney flashing to see how it holds up against the rain. We will work to touch up areas that need attention and replace flashing as needed.
Brick and Mortar Absorb and Seep Water
The brick and mortar on the outside of your chimney are not waterproof. Damage to the brick and mortar can form when water is absorbed into the brick or mortar joint and allowed to freeze or dry out. This process will cause cracks and damage to expand, creating a leak over time.
How To Fix: The Mad Hatter can test how fast it takes water to be absorbed into your brick-and-mortar. Depending on the results, waterproofing your chimney may be necessary.
Schedule Chimney Service with The Mad Hatter
Many people think they should call a roofing company if they have a chimney leak, but that’s not the case. Even though the two are connected, the roof and the chimney are entirely different structures. A professional chimney company, like The Mad hatter, has experience diagnosing and solving common chimney issues, including chimney leaks. This makes a chimney company the preferred choice over a roofing company.