Chimney Leak

The chimneys in Madison, Stoughton and other surrounding Wisconsin cities are exposed to extreme temperature changes and weather conditions this can cause serious problems if your chimney isn’t properly maintained. We recommend a yearly spring inspection to check for cracks and corrosion that might lead to bigger issues such as a chimney leak.

Ridge Top Exteriors chimney diagram

Chimney Diagram

The most common causes of a chimney leak can usually be pinpointed to the following:


Top View Coverless FlueCoverless Flue. If your chimney flue isn’t cover then naturally rain will come straight down, but it will also keep out snow, birds and other animals. Especially migratory birds such as Chimney Swifts which are illegal to remove without a federal permit.

Chimney cracked crownCrown Cracks. The bricks that make up the chase of a chimney are protected at the top by a crown cap constucted of concrete, metal or stone. The crown can be thought of as a chimney roof. Your chimney will start to show it’s age from constant exposure of weather elements. If your crown has even small cracks, water can seep down. In winter, rain and snow will freeze and melt which will force those small cracks to become bigger. It’s important to keep the crown checked, re-sealed and repaired if it’s impaired significantly.

chimney leak from damaged flue linerImproper Lining. A lining made of ceramic, metal or clay is a conduit installed inside the flue to protect the chimney walls from heat and corrosion by containing the combustible substances. If the liner is missing or compromised it can be extremely dangerous and MUST be repaired before the fireplace can be used. If it isn’t fitted and insulated properly this will lead to inefficiency, especially in gas furnaces as the fumes are low temperature with quite a bit of moisture in them. This allows condensation on the bricks leaving them moist and cold. In time, the inside walls will be susceptible to the wet build up.

Chimney flashing deteriorationDeteriorated Flashing. Flashing is a material that is installed at the base of chimneys, vents and stacks for a waterproof barrier where they penetrate the roof. Eroded or damaged flashing is the most common source of chimney leaks and water damage to your roof and likely to the interior of your home. This type of leak usually shows up in your attic first. To prevent problems it’s always wise to maintain them properly and inspect them each season. 

Chimney Missing MortarMissing Mortar: If the mortar between your chimney bricks is missing or cracked this will weaken your chimney structure and allow water in. This can also be extremely hazardous. Heating and freezing cycles can cause the mortar or worse yet, the bricks to break apart, leaving the areas susceptible to water absorption. If chimney cracks and gaps are left un-repaired long enough, the damage can accelerate rapidly with changing weather conditions. This could quite possibly result in the collapse of your chimney.

It’s also worthy to note that a chimney leak sometimes originates somewhere else but the water finds it’s way to the chimney by traveling along the stringer, (the long plank of wood that runs the length of your home and spaces out the roof trusses). It’s important to do routine maintenance and yearly inspections to ensure that everything with your chimney is intact. If you have any concerns about the integrity of your Dane County chimney structure or you already have a chimney leak, don’t hesitate to call us for a free estimate 608-249-0831.