I would estimate at least 4 people could live in a native American plank house, depending on its size. The later version of plank house built by the colonists and early Americans would comfortably hold even more. My grandmother's house still stands today and it held a family of 6 (parents and 4 kids). The original structure was 2 rooms on 1st floor and 2 rooms 2nd floor, built late 1800's. When modernized with indoor plumbing/electrical, an addition was put on, that added 1 more bedroom upstairs and kitchen downstairs. One of the original large upstairs bedrooms was then divided into a small bedroom, bathroom, and walk in closet.