Chimney Caps
By Dymon Brady
Recently, a customer of ours had a chimney that took away from the looks of their home. The concrete cap was falling apart in chunks. They had tried to paint it in an effort to hold it together and stop the eroding. Instead, the paint began to fall off along with the concrete, creating a mess all over their roof.
We fabricated a metal chimney cap, a protective structure designed to custom fit over the top of the chimney. Not only does this cap prevent further erosion and other issues, but it improves the looks of the home considerably.
The type of chimney cap and it’s implications will depend on the type of material that the chimney itself is made from. A chimney cap can be brick, stucco, concrete, siding, metal and copper, to name a few. The material that is best for you and your roof will depend on the needs of the functions you wish for your chimney cap to fulfill.
Pre-Painted Galvanized Metal
A metal chimney cap is a relatively inexpensive option. Metal will last longer than other materials, such as stucco or concrete, if it is taken care of properly. Be sure to select a metal that is 24-gauge or higher to provide maximum wind resistance for the dollar. The thicker the metal, the higher it’s wind resistance will be.
Copper
Copper chimney caps are a beautiful addition to any home. They are also soldered together, creating a watertight seal with no caulked joints. Copper will last up to 50 years with very little upkeep. Though it is a more expensive option, copper chimney hoods are often well worth the extra investment.
Traditional Chimney Caps
Other, traditional chimney cap options are constructed from brick mortar, cement, stucco or even siding. A brick mortar is easily constructed, though mortar has inherent problems. If you choose to install a chimney cap from brick mortar or cement, be sure that it is tapered so that water will easily flow off of the chimney instead of pooling and causing problems associated with the freeze thaw cycles that we are so accustomed to here in Utah.
Function and Design
In addition to tapering your chimney cap to allow rain to easily flow off, one of the most important thing to consider is that any pipes coming up through the cap for your fireplace, gas fireplace or furnace are flashed properly with a metal collar. This can be done by a professional roofing contractor.
You may choose to have a soldered chimney cap installed. This means that a metal is melted and flows into the joints, effectively gluing it together seamlessly. If you want this look, and it’s additional water-tight benefits, you will want to choose either a galvanized metal or copper (as shown in the picture to the left). Both of these metals will be effectively soldered.
Another option you may want to consider is how much upkeep you want to do with your chimney cap. A galvanized metal will need to be painted every so often to prevent it from rusting. However, there is the option of using a metal with baked-on enamel paint, which I tend to recommend. This metal will save time and money and will not rust.
Keep in mind that this metal is not able to be soldered. You will probably have to use a polyurethane caulk every couple of years to keep it watertight. This caulk has a 10 year warranty but rarely lasts that long. However, it is very inexpensive at around $5.00 a tube.
Fabrication and Installation
The average chimney cap will cost around $550.00 to fabricate. You can add at least an additional $1000 if you want a copper chimney cap. The total cost will vary from house to house, depending on the installer, the slope and angles of your roof, etc.
When attached, a lot of contractors will nail the cap on and put a dab of tar over the nail head. This tar will chip off and the nail will leak. If you need to attach it from the top, rather than the face (with a blind clip), you will want to use a neoprene washer screw, this will prevent leaks between the head of the screw and the top of the pan.