Should A Brick Chimney Be Sealed?

Growing up in southern states, you learn to always keep an umbrella or a rain jacket on you at all times. Between Mobile, Alabama and the panhandle of Florida, there is more rain here than in Seattle, Washington. Mobile to around the Tallahassee are in the direct hurricane territory. In the south, the only people who love the rain are the farmers. Precut boards are given to homeowners to cover each window. Also, there are sand bags for purchase at the local stores to keep water from entering the structure.

Homeowners here have come accustom to the weather conditions and now how to take care of their homes. Chimneys are left to wither away, but taking the steps to maintain the condition could save your chimney. Below are the types of chimneys.


Masonry chimneys, or brick chimneys, are constructed of a variety of masonry and metal materials. The materials include mortar, brick, concrete, concrete block, stone, flue tile, steel and a cast iron. All masonry chimneys will contain combinations of the materials, or possibly some of them. Most of the martials are affected by direct contact with water or water penetration.

All the materials, except the stone, deteriorate faster as a result  of prolonged contact with water. Typically masonry materials deteriorate quickly when exposed to repeatedly freeze-thaw stages. This is where water has penetrated the materials that froze and expands causing stress. Also, water in the chimney can cause rust on the steel and cast iron. Rust weakens or destroys the metal parts.


Prefabricated chimneys are built prior to installment or the development of the home. These are becoming to be the most common method of adding a fireplace into a home. Prefab chimneys function similar to masonry chimney, but cost much cheaper. There is a major design difference between the two. There is an offer the ability to vent a wood-burning fire from the fireplace and are built from sheet metal rather than the pounds of masonry. They do require similar maintenance requirements and have some drawbacks.

Water Prevention for Masonry

Resting at the top of the chimney is a chimney cap, or also called a rain cover. This is the most inexpensive preventive measure that a homeowner can employ to prevent water penetrating or damaging the chimney. Chimney caps are recognized as an important chimney safety and damage prevention component. According to Underwriters Laboratories (UL) specific that a chimney lining system must include a chimney cap.

There are other benefits to having a chimney cap. Caps are strong- well-deigned to prevent birds and other animals from entering and inhabitations. Also, caps function as the spark arrestors. Spark arrestors prevent sparks from landing on the roof or nearby combustible material. A proper chimney crown must be constructed of a Portland cement-based mixture and cast/form so it provides an overhang projecting beyond all sides of the chimney by at least two-inches.