I would like to span 15' to build a loft room above my living room what's the required floor joist without supporting beams?
Well without seeing you house in person... I am not so much worry about what's the floor joist requirements.. That shouldn't be hard to figure out. The worry is more how you planning to support the floor joist all the way to the foundation..
If it is a condo you lightly ok. But I don't see how you could get a beam that large into a condo.. If it is a house you are changing the dynamic of the support from a spread out load to a point load.
Unless you know what you doing or have an engineer figure out the support part. I will be very hesitant to ask a forum what floor joist is required..
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