Blythe Wood Works recommends that you stain and/or seal your new wood dog or cat house once it is assembled. Not sealing the house will void the warranty. We use a combination of Western Red Cedar and Select Cypress for the siding and roofs. Wood siding, especially the roofs, should be protected and not be left to weather naturally. This can cause splitting, excessive shrinking, and uneven coloring due to different exposure to the elements. If a weathered appearance is desired there are products that can help to achieve this. Western Red Cedar and Select Cypress are some of the easiest materials to finish. Quality coating systems can be used with confidence for a variety of decorative effects. This is an outstanding advantage of cedar and cypress -- it is not limited to one color treatment. Quality clear, semi-transparent, and solid bodied stains are excellent finishes. They are easy to use and available in a wide range of colors. They highlight the texture, natural grain, and beauty of the wood. Valspar from Lowes and Behr from Home Depot offer a good quality exterior deck stain and sealer. You may also want to check with your local paint store for suggestions on a product that would work best for your area.