DAY ONE

We spent the first day setting the concrete piers and building the understructure framing. The deck is supported by six rows of concrete piers laid parallel with the house. The rows are 25 1/2 in. apart, and each one consists of five piers. The most accurate way to lay out the 30 piers is to set the four corner ones first.

Start by placing the two corner piers alongside the house foundation (photo 1). Space them 14 ft. on center so the 16-ft. floor joist will overhang 12 in. on each end. That way, the decking will partially conceal the piers and make the structure appear to float on air. Temporarily place a perfectly straight joist into the slots in the piers, then check the board for level. If needed, dig out some dirt from under the high pier to level the joist.

You might also have to dig out from under the piers to ensure that the finished decking will be at least 1 in. or so below the threshold of a door. Once the joist is properly positioned, install three intermediate piers. These piers should be equally spaced between the two corner ones.

Next, set the two outside corner piers farthest from the house. Temporarily install a straight 2x6 joist between an outside corner pier and one of the piers alongside the house. Then move the outside corner pier to the left or right as needed until the joist is perfectly square, forming a 90-degree angle with the house.

Check to see if the joist is level. If the outside corner pier is high, dig out a little dirt; if it's low by a couple of inches, add dirt or gravel. To raise the joist more than a few inches, cut a 4x4 post to fit between the pier and joist. After you've leveled the joist, install four intermediate piers equally spaced between the corner ones (photo 2). Repeat this process for the remaining outside corner pier on the other side of the structure.