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Coveside’s products do not require paint or stain. Over time, the wood will darken and attain a weathered patina much like barn board and should last 7-10 years. The most important thing to be done toward long-term function is a thorough seasonal clean out after each nesting cycle, with soap, water and a brush. A light bleach solution, if need be, followed by a thorough rinse. Should someone wish to paint or stain, no petroleum based products, acrylic only, exterior only and not too dark a color to prevent excess heat absorption. Coveside’s preference for a non-toxic natural preservative is a light seasonal coating of either Tung Oil or Boiled Linseed Oil.