Freestanding Round Deck From Recycled Lumber

We had a shady area in our back yard under a corkscrew willow that was just begging for a nice seating area around the tree trunk. My wife and I mocked up a square deck but didn’t like the look at all. So we opted for a round, freestanding design that we both found more attractive.

The deck design was determined, in part, by the materials I had on hand. A local building components factory in our nearby industrial park tosses out their unused pallet grade lumber about once a week and it is free for the taking. The hardwoods and softwoods they discard are perfectly usable, just not usable for THEIR needs. So I had on hand a nice stack of 3x3 hardwood timbers, all 8 feet long, a bit green and a little warped. I also had a nice stack of 2x6's also 8 feet long and in decent shape. So my round deck dimensions and design were pretty much established by these 8 foot lengths.

We wanted the deck about 16-18 inches off the ground. The base is comprised of two “boxes”, an inner box and an outer box. The outer box is 8 feet per side and is built using treated 2x12's. The inner box, which sits on higher ground near the trunk, is built using treated 2x6's. We leveled up the two boxes, positioned then where we wanted them and temporarily held them in place by clamping on some 2x6's. We then positioned our first four “joists” We used four 4' 2x6's and positioned them exactly in the middle of each side of the inner box and each side of the outer box. (Photo 1) You can think of this as dividing the box layout (or circular deck) into four equally sized quadrants.

5/8" irrigation tubing was used to make a “hula hoop” with an outside diameter of 42". You can determine the length of tubing to cut by using the formula pi x diameter. In our case 3.14 x 42" which turns out to be about 11 feet. (Photo 1) The ends of the tubing are connected with an irrigation plug and the circle is held in position using some wood scraps screwed to the four joists. (Photo 2)

We cut all of the joists to just under 48" from our stack of recycled 2x6's. We had already placed the first four joists mid way on each side of our boxes, dividing our structure into four equal quadrants. The next 2x6 joist is placed from the corner of the inner box to the corner of the outer box basically splitting our first quadrant exactly in half. So we’ll call this a half quadrant. The next step is to split this “half quadrant” into a “quarter quadrant” by positioning another joist exactly in the middle or the prior two joists. All joists are placed with the inside tip resting against the irrigation tube circle and measurements on each end of the joists are taken to insure all the joists are spaced evenly at both ends. (Photo 1) Our quarter quadrant is then split in half one more time to give us an “eighth quadrant.”

Continue around the circle laying joists in the same way as the first quadrant. (Photo 2) This will produce thirty two equally sized pie shaped sections. Make sure all along the way that the joists are all evenly spaced on centers around the inner circle and then evenly spaced on centers around the outer end of the circle. (Photo 3)

Because our joists are so close together the decking itself does not have to span a great distance. Even at the outermost points around the circle the span is under 12". So I decided to experiment at bit and use 6' cedar fence pickets as the decking rather than the typical 2x6 material. This turned out to work fine providing a good solid feel under foot when it was finished.

Begin with the outermost ring of decking. We used 10" wide pickets (actual 9 5/8") for this outer ring in order to provide plenty of space at the ends to screw to the joists. The decking screws are 1 5/8" long. The ends of the fence pickets are cut at an angle of 22.5 degrees. To make for a nice fit the pickets should be cut on a power miter saw. Most of these saws have a stop that will set the blade angle exactly at 22.5 degrees since this is a commonly used angle. The boards should be cut to length so that they fit exactly on center of every fifth joist. The deck boards will span four pie shaped sections and end on every fifth joist. (Photo 1 and Photo 2) The inner rings of decking can be made using 6" wide pickets (about 5 3/8" actual size). You will quickly discover that fence pickets have some variation in width from picket to picket so you will need to vary the gap between pickets accordingly. Note that the deck boards do need a small gap between the boards to allow for expansion and contraction of the wood over time. Do not butt them directly against each other. Typically I use an aluminum yard stick laid on edge to position the deck boards. This provides a gap of about 1/8" between the boards. (Photo 3) Continue laying your deck boards until all the sections are finished. (Photo 4 and Photo 5)

In order to trim the perimeter of the deck to a fairly exact circle, 5/8" irrigation tubing is again used to create a guide. The tubing is cut to length using the formula of pi x diameter of your circle. In our case we wanted a final diameter of 140" so our formula was 3.14 x 140" or about 440". (Photo 1) Temporarily hold the irrigation tubing in place with nails placed every few feet. (Photo 2 and Photo 3)

Draw a line around the outer edge of the irrigation tubing circle and use a saber saw to trim the boards. We made our circle so that the outer edge of the deck was at least 1" beyond the tip of any joist. (Photo 1 and Photo 2)

Our steps were built using the recycled 3x3 hardwood timbers we had on hand. Your steps will most likely be quite different. Or if you build your round deck low enough to the ground you may not have steps at all. So this Instructable will not provide additional details regarding step building.

Even though the cedar fence pickets will weather quite well when left raw it is probably a good idea to protect them with either paint or stain. We used Behr transparent cedar tone waterproofing from a local big box store and are quite happy with the results. (Stained 2)