There are several modern chimney crown repairs products that allow you to easily repair cracks in your chimney crowns.
Because chimneys are situated on top of the roof, they do not have any sort of protection whatsoever against snow, rain or winds, leaving them totally vulnerable to the elements.
The chimney crown is designed to prevent water from seeping into the masonry below by covering and sealing the top of the chimney starting at the flue liners all the way to the edge of the chimney.
When the chimney crown gets damaged either by water or from cracks, you should consider repairs to it or have it replaced immediately in order to avoid any further problems
Chimney crowns are usually made from a variety of masonry and metal materials such as brick, mortar, steel, cast iron and tile and all of these materials will in time deteriorate because of prolonged contact with water.
These types of materials tend to deteriorate very rapidly when they are exposed to freeze or thaw situations and can also cause the steel and cast iron in the metal parts to erode.
Here are some of these chimney crown repairs products and how they work:
Crown Seal - a Premixed Flexible Waterproof Coating for Chimney Crown Repairs.
Crown Coat - a Brushable Sealant for Chimney Crown Repairs.
Crown Magik - Stops Leaks through Bricks and Mortar
Chimney Saver Water Repellent (comes in either water base or solvent base).
These chimney crown repairs products are simple and easy to use and come with full instructions on how to get the job done. To perform chimney crown repairs you will have to determine what sort of damage it is whether it a water problem or whether it is due to cracks.
If you discover cracks in your chimney crown you can replace it by installing a new chimney crown made from a Portland cement based mixture. The chimney crown can either be formed or cast and should have an overhang drip (also called a drip edge) which should extend approximately two inches beyond all the sides of the chimney.
This drip edge is necessary to allow the water to runoff from the crown away from the sides of the chimney, so as to prevent erosion of the brick and mortar in the vertical surfaces of the chimney.
You will then have to seal the joints between the flue liner and the chimney crown in order to prevent water from seeping into the chimney. Use a strong cement caulk product to ensure that you get maximum protection.
You will have to use a masonry caulking compound to seal minor cracks and the joint between the flue and the cap. For caps that are crumbling you will have to remove the old mortar, with a ball-peen hammer and a cold chisel and then you simply remove the loose dirt with a brush and apply a new layer of ready-mixed mortar with a trowel.
Be sure that it is sloped away from the flue so that water will be able to drain off properly. For repairs to the mortar around bricks, you will have to remove the old mortar and fill the cracks with a weather resistant mortar mixture.
Also you will probably need to replace flashing seals which is fairly easy to do. You simply remove the old mortar and caulk along the edges of the flashing and the joints between the flashing and chimney.
