Hi Dan and Pete:
Both you guys are adding very valuable info, and I agree wholeheartedly with all the added remarks, I also agee with Dan that this is probably not a task that you can handle without someone giving you a very professional opinion on whether you can do this or not.
Even with our combined experience we would approach this job with caution, by that I mean that the whole framework would need to be assessed to see if it would stand the process of being leveled up without major happenings taking place.
These timberframes are notorious for being stubborn in lots of ways, just try and take one down--it will resist demolition right to the end, and even when Mr Rot comes along and extremely weakens some of the plates the frame will continue to stand straight and true year after year. This doesn't mean that a weakened timber might give away.
One time I was just examining an historic barn with the intent of copying it for a restoration project, and luckily My helper and I were wearing our hard hats because one of the 4 by 4 corner braces which had becames dislodged because of its age and settling of the frame dropped straight down about 10 feet, along one of the corner posts. It could have ended my days right there if I hadn't had that safety hat on. Be sure and be very safety minded even if you are just poking around, the braces are very much a hazard in old timberframes.
Take care
NH
