Double Floor Joist. If we were to double up the joists to add additional support would that work. I see the Doubled FJs under bearing walls with and with out a space between to allow plumbing sometimes.
I am 80 yrs old. If we were to double up the joists to add additional support would that work. A beam is the main load-bearing structural element of a roof.
If you double the depth of a beam say by attaching a second 2x4 to the bottom of the first 2x4 thereby changing the depth from 1-34 inches to 3-12 inches you increase the moment of inertia by a factor of 8 since d doubles and I goes as the cube of the depth.
A 2 2x10 can span 10 feet and so on. From a three-dimensional perspective the floor joist framing would look like this. Double and triple joist hangers are wider to accommodate either a thicker piece of lumber or two or three joists placed side by side. In these cases the joist hangers will be 4x6 inches 6x6 or 6x8 depending on the dimensions of the joists.
