We live in a post and beam house. Much of the wood was stain dark brown, about the color of dark chocolate. Very ugly, and just sucks up the light. I have sanded some of the beams using belt sanders, and have more to do. This weekend, I ripped off the mouldings from a few of our windows. The moulding were wide pine boards stained the dark brown. I used caulk and great stuff to air seal around the windows. I then replaced the moulding with new pine boards. The new boards are 4″ (actually 3.5″) wide, and I am leaving them natural. I think they look much better. They lighten up the house. I definately felt cod air leaking in around the windows in spots. About my sliding glass door was the worst. There were little chunks our yellow foam pressed in there. I pulled these out, and sprayed great stuff in there to seal and insulate. I am making progress on cutting down the infiltration/exfiltration of air in our house. People have warned me about making our house too tight. Ummm, my house was built in 1977, and leaks like a sieve. The blower door test said the house leaked over 3000 CFM (cubic feet per minute). That is a lot of air! After I get a lot of this air sealing done, I can have them come back and do the blower door test, to see the amount of improvement.