Hey guys, just bought my home this summer. Any idea why there's a void (visible through the tub access panel down to the dirt) under the bathtub while the rest of the house is concrete slab? I see at least 1 joist that is completely rotted. The bathroom is full tiling.. floor and walls with jacuzzi tub, very nice. I'd hate to rip it up... just wondering what your thoughts are. Thank you!