Allsteel carries screws in 2 different lengths: 1½ inch and 2 inch. The 1½ inch variety is the best all-purpose size. The table below can be used to figure approximate quantities of screws for various purlin spacings and sizes of roofs. Screws are available in quantities of 250.
SCREW (purlin) SPACING
linear ft of panels
in your order 12 inch 18 inch 24 inch
50 270 180 135
100 540 360 270
200 1080 720 540
300 1620 1080 810
400 2160 1440 1080
500 2700 1800 1350
600 3240 2160 1620
700 3780 2520 1890
800 4320 2880 2160
900 4860 3240 2430
1000 5400 3600 2700
1100 5940 3960 2970
1200 6480 4320 3240
Again, be sure to clean away any metal shavings left after applying screws to the panels to prevent rust stains.