Typically we do not put any finish on the timbers. When first erected, the wood is very light in color, but will darken slightly over time. If you want a finish, we recommend you apply it when you paint the interior of the house, at the same time your trim is painted. We also recommend you use a breathable finish that will allow the timbers to dry (avoid using hard finishes like polyurethane or shellac until the timbers are dry). Timbers dry at different rates depending on species and humidity, but generally dry an inch a year. Most of the moisture will be gone after 4 years, but the timbers will not be completely dry for a few more years after that.