- Q. What is the best finish for the cedar shakes on a coastal home that is exposed to strong sun and lots of fine salt spray? Should the finish be sprayed, dipped, or brushed for best results?
A.Much depends upon the desired look. If you want a weathered gray look that is common in coastal areas, a clear water-repellent preservative can be used as a natural finish. It reduces warping, prevents water staining at the edges and ends, and helps control mildew growth. However, it does not, and cannot, maintain the new look of the cedar.
If you want the gray look immediately, a preservative stain is the answer. Semitransparent stains contain inorganic pigments, water repellents, and preservatives (mildewcides and fungicides). A semitransparent stain is more durable than a clear water-repellent preservative because the pigment absorbs some of the ultraviolet light, which deteriorates the wood fibers. Solvent-based (oil-based) stains are preferable to latex stains because they penetrate the wood surface and aren’t as likely to blister or peel. Latex-based stains and solid-color stains (whether latex- or oil-based) form a thicker surface film. While this film will guard against ultraviolet light, it may also peel or flake.
Dipping the shakes will provide the best coverage and will seal their cut ends, sides, and backs, reducing warping. Dip the shingles to slightly more than double the exposure, so the wood exposed in the cracks between the shakes will also be treated.
