Seriously hire an architect to walk the building with you . You ' d be surprised to know how many regulations and codes there are especially if you ' re changing the use of the building . A good one can give you all kinds of insight into the condition of the building , what code items need to be addressed , how the gym might fit in the space , what walls can come down , etc . Depending on your location , local zoning codes may prohibit the use of the building as a gym , the building may lack sufficient egress , fire protection , or structural capacity weights are heavy . Then you have the ADA laws of you ' re in the US . As a building owner those are your responsibility to comply with . Spending some money on an architect up front as part of your due diligence may save you substantially more long term .