I own a house built in 1920, and am considering converting the walk-up attic into living space. Today the space is used strictly for storage, and needs to be framed/drywall. I have read online about converting attic space, and people concerning themselves with reinforcing the joists. The attic I have already has a tongue and groove hardwood floor. It seems most of the projects I have read about where joists were reinforced there was not a "permanent" floor in place, rather just the open joists. I don't feel like ripping up the floor if it is not necessary. If anyone is familiar with building practices of that era-- if the hardwood floor was layed down at time of construction would it be relatively safe to assume the joists were constructed to support a floor and contents, rather than just hold the ceiling below? We are using the attic today for considerable storage and have not noticed any issues. Thank you.