WHAT CAUSES YOUR CEDAR SHAKE ROOF TO DETERIORATE?
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shedding of water, which promotes leaks and (2) After the rain stops, it prevents the surface from drying, which further encourages the growth of wood-rotting organisms.

Leaves, needles and other debris which is allowed to accumulate has these same two harmful effects. In addition, the debris increases the fire danger to your roof. There are several ways you may choose to deal with this debris and I would be glad to go over them with you. The point is, you must deal with it or your roof will rot away at a surprising rate.

HOW OFTEN SHOULD YOU REPLACE THE ‘NATURAL OILS’ IN YOUR SHAKES?
Never. There, wasn’t that easy? Actually the idea of “replenishing natural oils” in cedar shakes has been around a long time and until fairly recently was a concept to which most of us blindly nodded our heads. Listen to some of what Oregon State University Extension Service (Publication EC1271) has to say about so-called oil replacement.

“…these oils account for less than 3% of the total mass.” (And that was when the tree
was alive!) “…applying ‘replenishing oils to weathered shingles may be of questionable
value…” “…unless you include an effective mildicide or preservative, an oil like linseed
may provide an additional food source for mold, mildew and fungi…”

“Furthermore, petroleum based products are likely to be oxidized (broken down) by
sunlight, to have only a short-lived effect, and to increase the flammability of the roof.”

So once again, how often should you “replace” something that was barely present to begin with, that can actually encourage fungus growth, that works for a short period it at all, and that makes your roof more prone to fire? Never.

About half as often as you replace the natural oils. After a roof has been pressure washed, it looks “brand new.” That’s because it is. There is just one problem – the roof is now not as thick as it once was. Pressure washing tears away that silvery gray layer of wood cells, the presence and color of which could have been preserved. Your roof has now been made thinner by anywhere from 1/8” to as much as 3/16”. Then when your roof turns dark gray again, which it will relatively quickly, the idea is that you “renew” your roof by removing that

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