How It Works

Select the work to be done
Let us know what project you need help with and when you need it done - we'll match you with the right pros for the job.
Compare matched pros
Verify pro credentials, read reviews, ask questions, discuss availability, and request project estimates.
Complete your project
Hire the pro that's right for you and your budget. After the project is complete, let your community know how it went.
Powered by

The Home Depot

Common Sources of Chimney Leaks

Pro Referral > Home Guides > Fireplace & Chimney > Common Sources of Chimney Leaks
Common Sources of Chimney Leaks

Having a fireplace or a wood stove means you will also have a chimney atop your house. One common problem associated with chimneys is leakage. There are many reasons why leaks occur in a chimney. If your chimney develops a leak, then it can be a major cause of concern because gas hazards, insect and rot problems, as well as corrosion can result.

    Adopting some precautions and keeping a close eye on the condition of your chimney can help you weed out any problems right at the beginning.”
  1. 1.Think about the Future

    The building of chimneys is regulated and every area will have its own sets of rules to be adhered to. The stipulations can include the maximum permitted height for a chimney, specifications about the clay flue lining, and chimney caps. It is better to refer to these guidelines when you are considering repairs, to be on the safer side rather than be sorry later.


    Adopting some precautions and keeping a close eye on the condition of your chimney can help you weed out any problems right at the beginning. This can help save you a sufficient amount of money which you might have to otherwise spend on repairing other things in the house which might become damaged as a result of the water leakage from the chimney.

  2. 2.Possible Chimney Leak Spots

    Locating chimney leaks is not an easy task. Quite often the leak becomes evident only after the damage has been done. Leaks can occur anywhere on the chimney at any time. When attempting to locate the leak, you might need the help of one or two others. The top of the chimney which is also a mortared area known as the mud cap, is vulnerable to leaks. If this part cracks or comes loose, rainwater can enter into the fireplace. You may not notice the leak until you find water in the hearth or even elsewhere in your home if the water becomes diverted due to some obstacles.


    At times the mortar joints can develop holes that allow water to seep through. The deterioration of the mortar joints can be incredibly severe and large holes can form that allow water access to the interior of your home. Water that gets in this way can reach the ceiling or continue all the way to the slab.


    Another spot prone to water seepage is the flashing which is not so easy to pinpoint because even a very small hole can let in a decent amount of water. The roof shingles near the chimney can also lead to leakage if they are damaged in any way. However, this is not a very common cause of leaks.

  4. 3.Repairing the Leak

    The solution to your leakage problem will depend on the location and type of leak that exists in your chimney. If the mortar cap is the culprit, then you just have to replace it with a new one. Another option is to cover the entire top of the chimney with a metal cap. In the case of deteriorated mortar joints, the solution is to simply patch it up with new mortar.


    If you have a problem with the flashing, then you will be better off seeking the services of an expert rather than attempting to repair it yourself. This is because it requires sheet metal expertise that an amateur is sure to lack. If it is the shingles that are at the root of the leakage, then the solution would be to repair or replace these.

  5. 4.Beyond Your Skill and Knowledge

    You must remember that masonry chimneys are constructed with various materials such as brick, steel, mortar, tile, and cast iron. All of these are highly vulnerable to water damage and the risks increase in areas which see regular rain or cold weather. If you live in such an area you can choose to have your chimney waterproofed with the appropriate waterproofing agent. There is a wide range available in the market and you will need to consult a professional about the one best suited to your needs. If you think waterproofing is expensive, think again. It is bound to be much cheaper than the costs you will face when replacing expensive equipment, parts of your ceiling, dealing with mold growth, and so on damaged by water leakage.

Find Pros

Get your home project started today with help from Pro Referral’s qualified network of pre-screened and background-checked professionals available in your neighborhood.

Get Expert Advice

Submit your toughest home improvement questions to our knowledgeable experts and receive free personalized solutions, product recommendations, how-to advice, and more–all within 48 hours or less.