Wood decking should be attached to each supporting member (joist) with at least two 8d threaded nails or two No. 8 wood screws.
The illustration above depicts deck framing near a chimney or bay window. The ends of decking boards near the chimney or bay window can extend unsupported up to 6 inches.
The above illustration shows decking that is laid too tight. Decking should have 1/8-inch gaps between boards so that puddles don't form.
The above illustration shows decking that is properly spaced. Decking should have 1/8-inch gaps between boards so that puddles don't form.
The illustration above shows decking that isn't staggered properly. Decking should be staggered so that butt joints don't land on the same joist side by side.
The illustration above shows decking lengths. Some are too short. Each segment of decking should bear on a minimum of four joists.
Decking should be attached to the floor joists and rim joist, especially in high-wind areas.
Decking Nail Pull-Out
Inspectors should look for splitting in decking and nail pull-out. Aside from the structural issue, nails that have pulled out or lifted up, or screws that are not driven into the decking fully, can cause injury to bare feet.
Information used with permission of nachi.org