Join Date: Mar 2012
Location: Whidbey Island Washington
If you have a climate with a wet winter and a hot, dry summer, you are going to see space between the boards in the summer. You have to allow enough space between the boards for expansion and contraction based on moisture content. If you don't, when the boards swell from moisture, they'll warp and cause an uneven surface. When we floor a trailer, or build a deck, we use a pencil between the boards as spacing, so that spacing is consistent. If its very wet, and your lumber is very wet, a smaller spacer would be appropriate, but we usually do this in the summer, and a pencil works well.