What’s Causing Your Leaky Chimney?

A chimney leak is not only a hassle, it’s also a potential cause of major and widespread damage throughout your chimney system. Here’s some information you can use from the experts at National Chimney Cleaners of Morris County, NJ, and Fairfield County, CT.

Chimney Repair Norwalk CTWhy do chimney’s leak

Depending on the nature of your leaky chimney, you may be able to tell exactly why you’re seeing signs of water intrusion. In other cases, it may not be easy to determine exactly why the problem is happening.

To start with, watch for these signs:

  • White staining (efflorescence) on the exterior chimney masonry
  • A strong, musty odor coming from the fireplace
  • Loose or missing bricks; decayed masonry mortar joints
  • Water dripping into the firebox
  • Damp areas on the walls and ceiling near the fireplace/chimney

Let’s now look at four of the most common causes of chimney leaks.

1. Damaged or missing chimney cap or chase top

Chimney caps and chase tops (as well as basic flue covers) work to prevent rain and snow from getting into chimney flues. If these toppers are rusted out or otherwise damaged, water has a free path. You should never operate your chimney without a proper cover over the flue. These components can sometimes be repaired; in certain cases, the best move is to have them professionally replaced.

2. Breaks in the chimney masonry

When bricks begin taking on water, large problems can occur before you’re aware of them. The same goes for the mortar that holds the bricks together. Intruding water will freeze and expand, adding to the damage. If left unaddressed, a chimney’s masonry can become so compromised that it causes the structure to lean to one side or finally collapse. Solutions for this kind of chimney leak include brick replacement, tuckpointing to add strong new mortar, and the application of a waterproofing sealant to the masonry.

Flashing Repair, Greenwich CT3. Warped, rusted or missing chimney flashing

The flashing material that seals the gap between the chimney and the roof must be secure and solid. Damaged flashing will cause a chimney leak below the roof and affect unseen areas of the chimney as well as the building materials of the home. Damaged flashing should usually be replaced, and always by a chimney or roofing specialist.

4. Interior flue moisture

It’s not uncommon to have excess condensation inside a chimney flue, particularly when using a gas fireplace or insert. Gas fumes are not very hot and contain a lot of moisture. The quality, condition and size of the chimney liner can also affect how much interior moisture is produced.

If you can’t find an obvious reason for moisture in your firebox and musty odors filling your home, have your chimney inspected. If the problem is solely within the flue, there are various ways to address this. Note: when you speak with a chimney service company, make sure their inspectors are familiar with wood and gas appliances and vent systems.

Get on the road to a safer, healthier chimney

National Chimney Cleaners is ready to help with any situation that’s causing your chimney to leak. We’ll pinpoint the cause, repair any residual damage, replace components and advise you on how to prevent the problem in the future.
If you live in the Morris County, NJ, or Fairfield County, CT, regions, speak with a chimney expert today at 800-631-6177. You can also get in touch with our simple contact form.


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