Protecting the top of a chimney is important for many reasons. In New England, a chimney is most susceptible to climate damages in the winter. The top of a chimney will become saturated from rain and then when the temperature drops before the water has had a chance to evaporate, the freezing will cause mortar joints to expand and move and eventually open and crack, allowing more water to infiltrate over time. This occurrence, over a period of years can be very destructive. This is the primary reason a chimney cap is installed. It is also very important to repoint your chimney as often as it is required. A good repointing job will last several decades. Keep an eye out for cracks, missing brick or something as simple as missing mortar.
A chimney cap will also keep water out of the flue as well as animals or birds. Caps can be installed just to keep water or animals out of flues, rather than protect the whole top. Our caps today are copper or stainless steel and can be made in many different shapes.