I have recently become very interested in building a timber frame home and have been doing a lot of reading about joinery techniques. I have one question which I can not find addressed to any extent in the literature I have. Working with green timber, when a girt is joined to a post with a housed tenon, the girt will shrink in height and a gap will be left in the mortise above and below the girt. The lower gap is what concerns me as the girt would seem to be supported only by the pegs until the space disappears somehow- possibly by splitting of the tenon through the middle of the peg hole and settling of the girt by gravity until it bottoms out on the housing. Is this what happens? I am concerned about the slop caused by this shrinkage and wonder if it is a serious enough problem to be concerned about. I welcome any input regarding my thinking here and would appreciate any tips for minimizing the problem. Thank you, Gene