The "Good Stuff" and Why It Worked

Most tree trunks contain two types of wood: The "heartwood" which is in the center of the trunk and the "sap wood" which is the living outer set of rings. If we look at a cross section of a cedar log, we will find a 6" wide ring of sap wood at the outer edge (a light colored wood) and the rest of the cross section will contain the darker heartwood. The older the tree, the larger percentage of heartwood.

Heartwood cedar makes for the best shakes and shingles. It is the best for two reasons:

(1) The older heartwood has accumulated some natural toxins which reduce wood rot and insect damage.

(2) Heartwood tends to be straight grained, which means that it can be manufactured into shakes and shingles that will remain flat and true.

Shakes and shingles were usually installed on roofs with a steep pitch (6" in 12" or more); the style of the time. Such steep roofs shed water more easily; an advantage when you are working with a natural product which has some unevenness. In addition, most shakes and shingles were nailed onto strips of wood (skip sheathing) and neither felt nor tar paper was used. Such application methods maximized the drying process of the shingles and slowed down damage from wood rot.

These were wonderful roofs. You doubt my word? Take a trip to Lake Quinault (off highway #101 on the Olympic Peninsula). Stay at the Lake Quinault Lodge (you'll need reservations) after a nice breakfast...(OOPS! I am getting off track). Anyway, in the valley east of the lake you can see some old structures with 70+ year old shakes which are in very good shape.

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Cedar Roofs