New Wave Dave wrote:
"James" wrote in message

Thanks Marson, this is good info and good advice. I am printing it to
keep
for future reference.
Consider a built-up beam at the mid-point ABOVE the joists and then bolt
the joists to the beam using angle iron ala . . .

http://www.pbase.com/speedracer/image/2622653. We've successfully
applied this technique on a handful of jobs always, as in this picture,
removing a wall after the beam and angle irons are in place. These
happened to be 2X6 joists.

The OP is talking about a 20' span and a 40 pound live load. That'd be
about six or seven hundred pounds load on each connection, so it could
be done with a couple or three suitably sized bolts, but stepping over
a beam in a space you're using for storage isn't exactly a desirable
feature.

To the OP: most people that have objections to engineered joists
usually cite fire concerns, but as you're using the space for storage
and not habitation that's really not a big issue. So what's the
problem with using engineered joists. You might want to price the
floor assembly both ways before you make your decision. Lumber prices
haven't exactly been going down recently.

R