Hello, All!
I was hoping to get a little advice. I have a back area on my second floor I would like to finish off. The space is roughly 11 x 17 ft. The support is eight beams, 3x9", 16.5" on center, running parallel to the long dimension. It's old stuff-- house was built in 1870s.
Seven beams end on a header that spans the short dimension and goes onto the eighth joist on the one end and the external wall (brick on stone) on the other. The header encloses an old staircase, torn out below to enlarge the kitchen a number of years ago. The old stairwell is 31" wide, the header is also 3x9", and the joists the header supports are thus just over 14' long.
The eighth joist -- the one the header is hung on -- also supports a partition wall, also an old monster, plaster and lathe. This eighth joist is supported on the back wall, also brick on stone.
I want to put in two partition walls, parallel to the header and therefore crossing the joists. The space will thus be partitioned into three rooms, one of which will be a laundry room: washer, dryer, water heater, sink. At this point I am concerned about weight. I only have the one joist and header supporting the entire floor on the one end. So, what do I do? Remove the header and marry the joists into the opposing wall? Extend the seventh joist to the wall, and then hang a shortened header onto this? Extend 7, 4 and 1 to the wall, and hang two shorter headers on these, to which I hang 6,5,3 and 2? Nothing at all?
Attached is a very primitive diagram that I hope is enough to give an idea of the setup.
Thanks!!!