What spacing between boards on a deck?

[Tom Wassack]

Dennis,
I visited the Wolmanized website (http://www.archchemicals.com/Fed/WOLW/Docs/Outdoor/Building_Maintenance_Tips_7-07.pdf) and per their building tips, dry lumber should be gapped no more than 1/8 inch. That's close to my 16 penny nail diameter and after nearly a year of exposure and many wet dry cycles, my decking gap has never opened up enough to present a trip problem. So to answer your question, if using lumber dried after treatment, rather than wet dry lumber, I would leave some space between decking boards. Of course all is contingent on the dryness of the lumber at installation.

Respectfully,
Tom Wassack
Asheboro, NC