If you weigh 200 lbs.
Attic wieght limit.
My attic ladder is rated for 250 pounds.
A simple trick would be place your weight machine on a 8 foot x 4 foot 3/4 inch piece of plywood.
Strength of a material is obviously important.
Sistering is the process of adding a new joist next to each existing joist.
If you care about this, you will need to add a second layer of floor joists over the originals (perpendicular is best, to.
You've added about 300 lbs already when you put 6 sheets of plywood up there.
As larry said, don't overdo it.
Instead of the 40# piffin mentioned (which is the case for the other rooms).
Increasing the total weight on the floor to 4,480 pounds, however, results in a live load of 40 psf, which is beyond the floor's load capacity.
Bedrooms and habitable attic floors l/360 & 30 psf.
Design live loads will vary based on a number of factors, but at a minimum, 10 psf live load for attics without storage, 20 psf live load with limited storage, and 30.
However, if the attic is intended for storage, the attic live load (or some portion) should also be considered.
I just bought a new house, and my attic has ladder access (my previous house had stair access with a standard door, and i was able to walk into my attic rather than climbing up).
Dead load of attic floor when floored = 20 lbs.
Your attic will look good as new.
Normal sagging is 1/4 inch, which increases by another 1/8 inch over time.
Next, get a quality face mask (there's gonna be a lot of dust), slip on some gloves, and bring in extra lighting.
703.5 noncombustibility tests the tests indicated in sections 703.5.1 and 703.5.2 shall serve as criteria for acceptance of building materials as set forth in sections 602.2 , 602.3 and 602.4 in types i, ii.