Fire and water simply aren’t meant to mix – and that includes in your fireplace system. Water can be extremely damaging to both interior and exterior fireplace and chimney components. Because of this, it is important to be able to spot chimney leaks as soon as they happen.
What causes chimney leaks?
Chimneys are complex structures; because of this, there a number of areas where water can find its way in. While a chimney inspection is often needed to uncover the source of a chimney leak, the following are four common causes of chimney leaks.
- Chimney cap: The chimney cap sits on top of the chimney structure and protects the top of the flue from water, debris, and animals. With a metal top and mesh sides, a damaged chimney cap can let water flow directly into the flue.
- Chimney crown: The chimney crown is the masonry slab that seals off the top of the chimney structure around the flue; the chimney cap sits on top of the chimney crown. Because it is flat, the chimney crown often bares the brunt of the exposure to the elements. If the crown is not slightly sloped, water can pool on top and cause cracks, damage, and leaks.
- Flashing: Flashing protects the joint between the chimney and the roof. Made of layers of metal, flashing creates a watertight seal that keeps moisture out; if damaged, however, a leak caused by faulty flashing can damage both the chimney and the roof. Repairs to the roof-line, damage to surrounding shingles, or even being installed with too many nail holes can all cause flashing to lose its watertight seal. Many flashing leaks are mistakenly thought to be caused by a leaky roof.
- Masonry: While bricks and mortar are semi-porous – means they absorb small amounts of water – too much water absorption can cause cracks to form in the masonry. Even water damage to a single brick can quickly spread; the more damaged the masonry becomes, the more water it absorbs and the greater the chance of damage to the chimney becomes. Masonry with too much water damage can become structurally unsound.
Preventing chimney leaks
The best and most effective way to prevent a leaky chimney is through regular preventative maintenance. Yearly chimney sweepings and chimney inspections help make sure there are no damaged areas where water can get in; likewise, regular maintenance can help extend the life of your chimney and keep it burning safer longer.
Chimneys can also be protected against water entry by applying waterproofing products. Products designed specifically for masonry chimneys allow the bricks and mortar to retain their semi-porous properties; gas and water can evaporate out of the brick, but new water is not able to be absorbed. Waterproofing can also be helpful in slowing down deterioration in cases where the masonry has already been damaged by water.
Don’t let water entry cause damage to your fireplace or chimney; if you suspect you have a chimney leak it is important to call a chimney professional as soon as possible. Contact Mountain Man Fireplace & Chimney today to schedule a chimney inspection to uncover the cause of your leaky chimney – and prevent the leak from coming back.