Work Deck 12 x 20

 06 Oct 22:

We like decks near the Boat Works to roll projects in and out for sanding, sawing and to enjoy nice weather. Skipper found a shady spot behind the Boat Works for a 12x20 floating deck and we spent a few days laying out the blocking and rim joists, our variation on pier and beam construction. 

We repurposed some concrete retaining wall block, aka castle wall, to serve as the piers. Those were leveled with gravel and shimmed with pressure treated lumber in a few spots. Normally for a "floating deck we'd use 1 inch pavers as the pier, but his beck needed to be up a little higher to be level with the shed floor. 2x6 pressure treated joists are set on block, 24 inch on center. The allowable span for a 2x6 yellow pine on 24 inch centers is 7' 7", so we placed a block at 6 feet mid span on each joist. Rim and floor joists were fastened with Grip Tite deck screws. 

Here we are working our way out from the shed, checking for square. We could have gotten 2x6 in 20 foot sections, would have delayed us a few days for delivery, but decided to grab the first batch of shorter boards ourselves with the trailer and get started. We alternated 12 and 8 foot boards around the rim and on the deck, deck joists are just under 12 feet. 

Deck Joist Sizing and Spacing

Skipper nowhere to be seen when 50 pound bags of pea gravel and 20 pound blocks are being tossed around. It took a couple of afternoons to get to this point.

Mid morning on the 6th we had more deck planks delivered, and got a fair number of them tacked into place before the End Work whistle blew.

2x6 decking, spaced 1/8 -1/4 inch apart, as we like a gap for rain and leaf debris to get through. Turns out a carpenter's pencil is 1/4 inch wide. Now this gap will increases as the wood dries, as much as an 1/8th inch or so, so that gap may get as big as 1/2 inch. That's okay with us, we like the airflow to keep things dry. Another way we avoid rot is to buy ground contact rated lumber and set it on concrete. The pea gravel also promotes drainage and drying. 

Log of Lewis Boat Works.