I am preparing to jack up a small two story cottage, it was built on dirt and has sunk over the last 50 years to the point where I am worried about rot. I have received what I think are some good tips about how to do this from another family who jacked theirs up a couple of years ago. My plan is to slide I beams under the length of the cottage and then jack up the beams until some supports can be dug and poured. My questions are what size beams would be appropriate, and which direction should the beams be positioned lenthwise (parallel to the original supports) or widthwise. The cottage is about 30x20 and about 1000sf overall, the front porch (10x20) is open to the roof, so it looks like this:
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| |
| Main |
Len 30ft | Building |
| |
| |
|----------|
| Porch |
|----------|

Wdth 20ft

My house sits almost flat on the ground, possible joist damage. I want to raise it 16", but I'm not sure of the best (most economical) pier system. What did you use?