Has anyone ever done a partial to full basement? A lot of dirt needs to be dug out and a concrete floor poured in. If I had my druthers I would just level the whole house and start over(from single floor to 2 story house)but money is a big issue for that lol. What would the cost of doing something like that be?
your main issue is that the partial side likely does not have wall and footings going down full depth. This means the house would have to be jacked a foundation repoured in the form of a full basement.
Also this would be very expensive because with the house on top its not like they can just come in with a backhoe.
You need a PE or architect to properly answer this question, based on the type of foundation you have, and what is required to make sure digging in close proximity to the existing foundation doesn't cause it to give way...
Up in these parts, you'll need a permit to do this type of work, and implied with this are a set of stamped engineering drawings on what exactly needs to be done to ensure a good foundation for the home.
I actually helped a guy do just that several years ago.
What we did, was instead of digging to the edge of the house, we left about two feet of dirt. We did not disturb the footers. We started digging with shovels and picks, but it was slow going. When we hand dug down far enough, we got a Bobcat and dug a ramp from outside to the same level as what we had hand dug. We supported the floor joists with a steel I-beam and adjustable posts, and went through the short foundation into the hand dug hole inside. From there, we dug out the rest with the Bobcat. We then dug a footer trench and poured footers. We then laid a concrete block wall that reached the ground level outside. Then we poured concrete on the inside two feet of dirt which we left inside. That sealed the space. We then poured a concrete floor after which we filled in the ramp outside and blocked up the remaining hole.
After all of that, we cut a hole in the floor above and put in a stairway.
It was kind of a neighborhood project that took most of the summer and early fall.
Looking back at our experience, I wouldn't recommend doing it.
Could you clarify what you want to do? It sounds like you now have a basement under part of your house and a crawl space under the rest and you want to dig the crawl space out to full basement depth. Is that correct? It would also help to know how large the area is.
Sketch to understand the framing, footing and some dimensions could help to clarify what would be possible.
Removing significant soil around a foot can cause rotation or failure of the soil, and then footing. 1-2 test pits that are limited in size adjacent to the existing foot can help give you an idea how far you can go down. Footing condition itself may dictate whether this is possible or not, or how you approach building out the basement.