Andy Francke spaketh...

"McQualude" wrote in message
something to play with...
http://www.cwc.ca/design/design_tool...2002/index.php

This calculator doesn't seem applicable - it only shows 2x members.
What we have are sistered 2x8s or 10s. Further, this only deals with
spacing up to 24", nothing wider. My joists are 48 o.c.

That was point Andy, to demonstrate that you have a serious problem;
however, I note from your later posts that your information was inaccurate
and the problem may not be as serious as first appeared. Still, it might
not hurt to have someone take a look.
--
McQualude