Hi”,Joe, there is one way, which I know works some
times,and that is run a lentgh of timber ( 4″ x 1″)
along side the joist,( now this is the trick ) screw
ends of the timber to the joist right up tight to the
floorboards, when you’ve done that push it up to the
floorboards with a 3×2, wedged off the ground then
screw the 4 x 1 to the joist every 10″ or so, repete
this along the timber ( move the 3×2 along then screw)
Hope it works it did for me. ….John 2000