Cedar shingles have been the material of choice for many roofs, especially in the northwestern US. Before the 1950s there was plenty of cedar heartwood, the part closest to the center of the tree. It was hard, could be cut straight, and had natural toxins against insects and rot.
Common problems with cedar shingles
Although cedar shingles are traditionally made from the heartwood, today’s shingles are often taken closer to the outside of the tree This wood is called “sap wood” and is inferior to heartwood in several ways: it doesn’t cut in a straight grain and it hasn’t developed the natural toxins of heartwood. This younger cedar is subject to fire and wood rot. Also, most roofs aren’t pitched as steeply, so less water runs off.
Fire danger is severe. It isn’t wise to have a cedar roofed house in an area surrounded by trees. No matter where the house is, cedar roofs should be treated with a fire retardant.
Cedar shingle ratings
Buy only cedar shingles that are number 1, blue label rated. Examine each shingle in a bundle as inferior grades are often mixed in. Quality and properly cared for cedar shingles can last for 30 years, withstand hail storms, and winds up to 130 mph.