wooden deck spacing

[p_leyden]

I am replacing the wood decking (2x4's) installed 30 years ago and replacing it with some more 2x4's. What spacing between adjacent boards should I use. Last time I spaced the boards 1/4". I am thinking 1/2" spacing would  allow the boards to dry faster.
Any thoughts?
Thanks!

[Robert Adams]

I never put any spaces between boards when using pressure treated wood on decks or on wood fences. The boards will start to visibly shrink within days of installation. The wood is soaking wet when you get it unless you get kiln dried pressure treated then that's a different animal but it is only available from commercial wall suppliers.

[Snipe Hunter]

I guess it all depends on how wet the wood is and what you would like it to look like when they're dry. They just have to drain, so that doesn't take a lot of a gap. I generally use framing nails for spacing decking boards but it really depends on the dimension of the deck. I don't want to have to cut a real narrow decking board at the end of the deck if possible.

I used to jamb them together and I'd get a gap between them when the decking boards dry. But the last time I did that, they didn't shrink much and it was very difficult to keep clean, actually had some little maple trees growing between the boards.

So, wider than a maple seed is my final answer.

[hbmcc]

Camo determined my decking gap. 3/16". And, it's too narrow to let Big-leaf Maple seeds slide through. It's actually a tighter spacing than what I had previously, and that was too tight also. The present spacing looks a lot nicer, and your high-heeled friends will appreciate that difference.

I know I am in my honeymoon phase right now, but I found certain, wider, gaps harder to clean and keep clean. There was a sweet spot that the pressure washer was more efficient in cleaning. I am hoping the 3/16th inch space is it. 

My contractor did the access ramp butting the Cedar boards, at the same time he did the main deck the way I asked him, about a quarter inch. The butted boards never did shrink--they expanded--and the wood was rotten after a few years. I re decked it about 10 years ago, maybe, more. My decks were 3/4" and now are 5/4 (1" net).

Visually, you might think a half-inch is close enough. At some point the spacing will make it a window and wall maintenance access, rather than a recreation surface; or you are a sailor. I got that feeling when the contractor was matching the outer boards spacing on my main deck, about 5/16" to 3/8" gap. You have another problem if a half-inch seems necessary.

[mike4244]

I am replacing the wood decking (2x4's) installed 30 years ago and replacing it with some more 2x4's. What spacing between adjacent boards should I use. Last time I spaced the boards 1/4". I am thinking 1/2" spacing would  allow the boards to dry faster.
Any thoughts?
Thanks!

Larger spacing does not promote faster drying. If boards are not kiln dried which I doubt they are ,no spacing at all. They'll shrink on their own.

[KC]

Deck at our Nebraska house has spacing of nearly in inch.  
  No telling how much crap has fallen in there over the years.  Dropped my keys last we were there.  

[Foggy]

I used 16D nails as spacers. Nailed through a scrap piece of board so it can lay across fixed deck board and loose one with nail down between them. Jam tight and fasten deck board. Use several for crooked deck boards. Still good after 15+ years.

[Cecil]

I installed 2x6 treated, and used a putty knife for space.  However, no spacing is really needed, like others said, since all that water will dissipate after install.