I'm sure this has been covered in detail in previous threads and I apologize for starting an entirely new thread about this but I imagine this is going to end up being a long drawn out and in-depth process and it might be best to tailor this thread specifically to my house.
First a little about myself. I'm twenty-six, in between finishing an engineering degree, and have worked professionaly as a welder/fabricator for the last seven years. I've worked with hydraulic jacks undecking shovels and draglines that weigh upwards of several thousand tons so I'm comfortable doing jack work whether it be done by a manual hand crank or hydraulic ram. On to the problem.
I purchased a house last November 09 and have just recently moved into it in the summer of 2010. Aside from a slew of plumbing problems the house seems to have settled by several inches (I'm guessing at least 6-8") to the the northwest corner. There is a basement with a ceiling height of approx. 6'7". There are several problems aside from the obvious settling. However, on the plus side the foundation appears to be in good condition without any cracks in the walls themselves, the floor however has some tiny surface cracks but none that have opened up more then a few millimeters.
What I'm looking at doing is replacing ALL of the floor joists. The house was originally constructed in the late 1800's (I think the paperwork said 1886 or 1896). And has since had an addition built onto it as well as a deck. The floor joists are made of 2x6" pine. I'd guesstimate that twenty-five percent of the floor joists have cracked completely in half at one time or another and as a result were sistered on both sides to reinforce, however even that seems to be drooping. The reason I'm considering replacing all of the floor joists is I want to replace the 2x6" with 2x12". Obviously this is going to take quite a bit of planning and require a sufficient amount of funds to replace siding, water lines, electrical lines etc... I'm planning on spending at least the next year or two years planning this endeavor and acquiring the materials to do it. Since I am in the early stages of planning any recommendations would be greatly appreciated. I'm not concerned about cracking the drywall in the house as I'm planning on replacing all of it and the insulation behind it.
Anyways, it's late and this was on my mind so I figured no better time then the present to start thinking about it. If pictures would help I'd be more then happy to take pictures of everything and post them to help anyone get a better idea.
Thanks in advance for any responses =)