A.William Feist responds: Unless you shrink-wrap each piece of cedar, it will darken and eventually weather to a silvery gray, or worse, to a blotchy dark gray. Clear finishes with UV inhibitors will slow down the weathering process, but these still need to be reapplied every two years or so. Eventually the color will change anyway, even indoors.
The best thing you can do is to approximate the color of new wood by putting on a cedar-tone stain. First, install the siding with the rough side out. A smooth surface holds less finish and weathers much quicker than a rough-sawn surface. Finish the rough surface with two coats of a lightly-pigmented, semitransparent, oil-based stain. Be sure to...
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