I am building a hybrid timber frame home, which will feature some exterior posts and beams for entry and porches, as well as interior timber frame portions. I am not as worried about finishes for the interior, as there are quite a few choices that will likely work quite well, but the exterior finishes I have had trouble with in the past.
I have used Sikkens Cetol 1 and 23 formulations for exterior timber frame posts and beams and found that this works quite well for up to about 5 years, and then it begins to peel and discolor with mildew and exposure to the sun. I have stripped these posts, sanding meticulously and reapplying both formulations carefully in the recommended conditions but find that the finish does not last long and needs to be refinished often.
Has anyone found a better product to use in this type of situation? I am thinking of using a penetrating oil finish for the interior millwork and wonder if one designed with UV inhibitors would be appropriate for exterior use......Any advice on the experience of others would be appreciated.