Melanie
Old houses have "charm", but that charm can sometimes cause problems. My house was built in 1919, with a dry stone piled basement. not anywhere near as old as yours, but even it has it quirks.
I agree with the others, that before you do anything, get your humidity under control and see what you have when that is done. Put some inexpensive throw rugs and runners over the damaged areas.
If the floors are original, you have moved away from a traditional flooring business. You're looking for "that guy/gal", and they do exist, that isn't as interested in getting your floors flat as quickly as possible, but rather working with what they have to preserve the historical charm. It may take a couple of seasons to "tighten it back up", but if you're patient, it will be worth it.
If you're willing to do the work yourself, start with a random orbital sander and work the most damaged ares first. Use a higher grit, say 120 and above, and just go slow. To abrasive a grit, will remove material too fast for your experience level. Avoid the siren song of the hand held belt sander. If you're not really experienced with one, you can really muck up the floors worse than what you already have to deal with.
Make sure you have the sander hooked up to a vacuum,( There are many systems available) and wear a dust mask. The finish by itself, and years of grime, dirt, animal dander, bacterias, and who knows what else that will come up, are much, much, worse than just wood dust. Protect your lungs.
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Contact a professional finisher to reapply the floor finish when you're done. Start small and teach yourself as you go and you'd be amazed at what you can accomplish. Just go slow!
BTW
If you were to ever choose to replace that floor, you have no idea how much money those boards are worth. Cupped, damaged, and all.
Last edited by Mike Cutler; 09-23-2017 at 10:38 AM.
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