Ice Dams & Chimney Damage
Ice dams, which are patches of frozen melted snow that sit around the base of a chimney, can cause a lot of serious problems if ignored. In Massachusetts, we have winters that are cold enough for ice dams to easily form and last for a long time. Here are some things you’ll want to know about ice dams and chimney damage.
Most common places for ice dams
Chimneys set into the roof below the roof line (i.e., not jutting out from the highest point of the roof) are susceptible to ice formation as they block the runoff of melting snow. The water pools, and when the temperature drops back below freezing, you’ve got ice.
We’re talking specifically about chimney issues here, but ice dams can form and cause roof damage at the end of any recessed areas of your roof where water isn’t able to flow into the gutters or down to the ground.
How ice dams affect chimneys
Chimneys and their components work together to perform several jobs, one of which is keeping water out of the system. When ice patches are allowed to remain in contact with the bricks and mortar of a chimney, significant damage can happen due to water infiltration and the freeze-thaw cycle.
It’s not uncommon for chimney bricks and mortar joints to have small cracks. Additionally, bricks in their perfect state are porous and absorb moisture. Water inside cracks or brick surfaces will expand when frozen, exerting pressure in every direction and opening up larger spaces.
We call it a freeze-thaw “cycle,” because South Shore winters have many fluctuations of temperature above and below freezing. When it warms up, water moves into cracks; when it freezes, it enlarges the cracks; when it warms up again, more water gets in, and the cycle continues.
It doesn’t take long before bricks and mortar begin to degrade to the point that the chimney is no longer safe to use.
Other areas of the chimney system that can be harmed by ice dams include the chimney flashing, which seals the gap between the roof and the exterior chimney, and the concrete chimney crown at the top of the chimney if ice forms and is allowed to remain on it.
The value of a professional chimney inspection
Not all ice dams result in damage to a chimney or its components. But many do. This is why it’s a good idea to schedule a thorough chimney inspection once a year with a licensed, certified chimney professional.
Often performed in late spring when the weather clears up, a chimney inspection will detect any early signs of masonry damage and damage to the chimney crown, flashing, cap and other components. You can then have the necessary repairs done and ensure that your chimney is safe to use the next burning season.
In addition, yearly chimney inspections will spot other problems including venting issues, damage from chimney fires you didn’t know about, structural concerns and more.
Above & Beyond Chimney Service of Dedham, MA, is a Massachusetts Licensed Contractor and member of the National Chimney Sweep Guild. Our lead technicians are all professionally certified through the Chimney Safety Institute of America, so you know you’re getting work done correctly and by experienced individuals.
Call us for chimney inspections, chimney sweeping, chimney repairs and all other needs. Speak with an expert at (781) 383-0415.