It is often the case that fireplace retailers and chimney cap manufacturers make quite a few pretty confusing claims regarding the need of using a chimney cap and the type of cap to choose. However, fact is, in order to be able to choose an ideal chimney cap, it is of utmost importance to pay attention in advance to the type of chimneys used. In this case, the cap that will be discussed is that for the metal chimney.
A metal chimney is often used for a lot of pre-fab fireplace and wood stove installations. Gas ventilation often makes use of this particular kind of chimneys as well. In most cases, a metal chimney is the kind of chimneys that really need to have a cap. There are quite a few reasons why it needs a cap.
One reason is that without a proper chimney cap, rain will have nowhere to go. As a result, the rain is very likely to run into the heater, fireplace, or stove. In addition to that, ceilings and walls can often take damage as well due to this factor. The next reason is that without a cap, the chimney will become quite convenient for birds along with other animals to warm themselves. Even worse, the animals may clog the chimney with their nests. Yet, with a cap, they will be kept out of the chimney.
Another reason why a metal chimney may well need a chimney cap is because it often comes manufactured with 2 to 3 metal layers that have insulation or air in between. A proper cap may well prevent moisture as well as water from getting into the metal layers. This is critical because a premature chimney failure or other problems may take place otherwise.
Fortunately, the ideal chimney cap for a metal chimney is already preinstalled on the chimney itself most of the time. This cap is provided by the company that manufactures the chimney. The cap is already pretty ideal because it has been made specifically for the brand of the chimney sold. With that being said, the owner of a metal chimney is not likely required to find any aftermarket cap, except in some cases. This is when there is a wind or draft problem or if the cap is exhausted yet the owner can no longer find the chimney manufacturer.
Anyway, if it is the draft that is having some problems, the owner can simply use a vacuum chimney cap or the so-called draft increasing cap. Such a cap attempts to create a more powerful updraft by taking advantage of the wind.