At Edmund Allen Lumber, we have been finishing cedar and related siding products at our facility since 1962. Numerous studies have been done and the results are unanimous: Factory Finishing is the most uniform, economical, and effective way to protect exterior siding and trim. With real wood siding such as cedar, a US Forest Products joint coatings committee study determined that adhesion on “raw” boards was compromised with as little as two weeks of exposure to the elements.