Your chimney has what is called a chimney pipe that leads from the fireplace to the top of the chimney. In older chimneys, that chimney pipe is simply the brick chimney itself. In other cases, it is a cylindrical metal pipe known as a metal chimney pipe. A metal chimney pipe can help preserve your property value, but it will not do a great deal to increase it. In some areas, metal chimney pipes are required by law. Installing one in that case will save you money on fines and could help preserve a future sale of your home. The metal chimney pipe also helps to make your fireplace more energy efficient by trapping the heat that brick chimneys allow to escape.