Patent ID: 7752823

Claim:
A metal building roof comprising a plurality of substantially parallel purlins extending in a first direction, the purlins having a center web and being supported at intervals by structural building frame members, and a plurality of braces extending in a second direction, substantially perpendicular to the first direction, between neighboring purlins to prevent lateral deflection and twisting of the purlins under load, the improvement wherein at least some of said braces are channel members having a central web and upper and lower flanges, the flanges extending lengthwise beyond the central web at a first end of the brace to form a pair of protruding tabs one above the other, the purlins having pairs of longitudinally-extending slots at intervals so that the tabs of a brace can be inserted through a pair of the slots and protrude on the other side of the purlin one of said slots in each pair being above and substantially parallel to the other, the brace having holes in its tabs at its first end, and holes in its upper and lower flanges at its second end, the holes of the tabs and the holes of the flanges being disposed so that they present a visible and observable alignment from above when the respective members are abutted firmly against the purlin web on opposite sides thereof, whereby the tabs of one brace may be inserted through the slots in the purlin web from one side of the purlin and another brace may be applied from the opposite side of the purlin so as to overlap the tabs, and a plurality of drop-in pins, each of which may be inserted down and through the aligned holes of the first and second braces to interconnect them on said one side of said purlin and on the opposite side of the purlin respectively.