new floor joists in attic

[nowdue]

hello

i live in an early victorian terrace and am converting the attic. how much load can an 11" square, 8 or 9 yard wooden roof beam take? i am thinking of hanging floor joists from it, these being supported at the other end by a supporting wall. the beam spans the width of the house and is supported by brick walls.[img]http://redrobot.weebly.com/[/img]

[nowdue]

this is a plan of the above [img]http://redrobot.weebly.com/[/img]