okay...these would be perpendicular in orientation to the joists...not secured to the joists between the joists.
..-------========-----
..........[]...............[]
the [] being cross sect of the floor joists
the --- being the subfloor seam
disregard the .....'s they are for spacing.
the ===== being subfloor edges both sides
each side being over half of the side of the flat 2x4 and that 2x4 is centered under the seam from the crawl space side.
From what your saying I'm imaginging
that you have 2 each 2x4's, stacked ontop of each other that are held on top of each other by metal strapping so its trying to create a 2x8"? so if each ===== is a 2x4" and you look at the side view of a joist facing it it looks like this?
______________ sub-floor
============= first 2x4
============= second 2x4 under
open crawl space below.
is that right? and that they are strapped on
the side faces (4" deep side or rather 3-1/2" side)like this:
....____________ sub floor above
....[]\__/\__/\_ [] is top 2x4 sits on top
....[]_\/__\/__\ []lower 2x4 with /\ strap
..................crawl space below
Moderated by Handyman 
