The answer to the question "can treadmill be used upstairs?'' is going to depend on many different factors. But for the most part, in a building that is structurally sound, the floors should easily support 50 lbs per square foot. So in a room that’s 100 square feet, that’s 5,000 lbs of weight needed before you risk structural damage!. The heaviest treadmills out there reach about 350 lbs. Even, if we put a 300 lb person on top of that treadmill, that's just a combined weight of 650 pounds.
