Brick chimneys are systems in which all components must work together to ensure that water cannot invade your home. It is important to understand all the components of a chimney which can fail and allow water entry into the chimney and allow water into your home. These include water down the flue of a chimney with no chimney cap, a chimney crown which is porous, or instances where water can circumvent the chimney counter flashing system. We will look briefly at each of these and provide a links to comprehensive information elsewhere.
Water problems relating to aged brick chimney crowns are common.
If you have not seen the overall condition of your chimney lately, an inspection is in order. A porous chimney crown allows water to penetrate through the brick rather than properly run off the crown, down the sides of well-maintained and solid brick siding, until the final transition over the counter flashing and onto the roof.
While many chimneys are often “out of sight, out of mind,” even a cursory view from the ground may often indicate brick or mortar damage caused by a faulty chimney crown or severe weather, soft brick, or a combination of factors.
More information on Brick Chimney Crowns.
Water staining in your firebox indicates leaking into the flue, usually caused by a missing chimney cap.
The water stains in this brick firebox testify to a water penetration problem at the chimney level. Water is likely coming through an uncovered flue. It’s important to differentiate water coming into the firebox, which could simply be entering through an uncovered flue, from leaks caused by flashing problems, cracks, or deterioration in the chimney structure which are coming through the ceiling or along the exterior of the brick.
If the chimney is in good shape, and water is coming into the firebox, the flue is likely uncovered, and the chimney may simply need a chimney cap.
Brick & Mortar Cracks and deterioration on the sides of the chimney can allow water to enter and circumvent the counter flashing.
The basic integrity of your brick and mortar impact your chimney’s ability to shed water properly. The brick and mortar of your chimney above the counter flashing could be cracked and/or deteriorated, thus porous and allowing water to outflank your flashing materials. Your chimney flashing could be sound, yet you could still have leaking problems if the masonry is porous due to cracks or deterioration.
An experienced repair mason can check out your chimney thoroughly. Patches or spot repairs are usually ineffective and can allow further deterioration and frustration. You can see the impact of spot repairs in this discussion of chimney flashings.
The image below illustrates the issue of brick cracks impacting the ability of the counter flashing to properly shed water.
Cracks in a brick or stone chimney will allow water to enter the chimney.
Chimneys are a system of component parts.
Each component requires examination by a competent brick mason to understand the extent of a leaking problem, whether the brick chimney is contributing to the leak, and to provide the proper scope of a solution, if the masonry shows signs of contributing factors.
Did we answer all your questions about chimneys? We have more specific information about brick chimney counter flashing and roofing assemblies here.