Chimney Crown Repair
A chimney crown is the masonry cap located at the very top of the chimney. The crown acts as the roof of the chimney protecting the structure below from the harmful effects of Mother Nature. Traditionally, a properly constructed chimney crown would be made of Portland Cement. However, in recent decades more and more crowns are being made with mortar. There is no other reason for this substandard construction other than laziness. The mason finishes laying the bricks and then pores the leftover mortar on top and creates a crown. Mortar is not designed to be used for large surface applications. As the owner of a chimney business for over 25 years, I have actually seen mortar crowns crack even before they are done drying. If your home was built after 1970, there is a very good possibility that your crown was not made to masonry institute standards.
But even a properly built Portland Cement crown has a limited life span, generally 7 -10 years. Whether your chimney flue, that passes through the crown, is made of metal or terracotta, it is constantly contracting and expanding. This constant fluctuation is due to use or normal climate changes. When you surround an ever changing flue with a material that does not have the capability to expand, all these materials will eventually crack.
Until recent years, the only option to a repair a damaged chimney crown was to remove the old crown and pour a new crown. Removing one material with a limited life span and replacing it with the same material made no sense to those of us at WeatherTite Industries. Decades of experience taught us that chimney crowns will crack long before significant damage is seen from the ground. A cracked crown is generally still a sound structure. However as water enters the cracks it will begin to slowly deteriorate the structure or cause annoying leaks.
Tearing off a crown with simple cracks can be an involved job. Removing the crown can also lead to other problems such as knocking Bricks loose or damaging the flue.
Using one of WeatherTite elastomeric coatings such as CrownTite Or Flexible Crown is the most effective way to repair a cracked chimney crown. Both of these latex/acrylic coatings are designed to resurface the existing cracked crown. Once applied Flexible Crown and CrownTite will remain flexible and are unaffected by the normal contraction and expansion that takes place at the top of a chimney. Flexible Crown and CrownTite will both keep any additional water from entering the chimney through the crown. Both products carry an unmatched warranty of 20 years. So if your chimney is in need of repair, demand that your contractor use only the best products, backed by the best warranties in the industry.