I will be building a small lean-to shed and want to set the posts holding the roof into concrete. The standard procedure is to dig a hole, set the post, pour concrete to almost fill the hole then add dirt. Question: if I want my posts to last longer, should I seal the bottom part of my (pressure treated) post that comes in contact with conrete and dirt with anything? Either the end grain or the sides? I know that I should put gravel on the bottom of the hole under the post, but if I can add some extra protection by sealing it, I can do it. What sort of sealer would you recommend? TIZ!