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Building the Frame We first laid six full length (96") 2'x 4's horizontally (Fig. A - white lines). To make the interior "joists" we then cut the remaining twenty-six 2' x 4's down to a length of 93.75". Four of these pieces became the outer edges of the frame, and two were placed at the frame's center, 96" in (Fig. A - blue lines). Because we needed the platform to support a significant load without flexing, the remaining joists were laid 16" on-center (Fig. A - red lines). Otherwise, a distance of 24" on-center or more would have been adequate. Notice that while the central and side beams were laid directly opposite one another to provide support at the edges of the OSB, the joists were offset from each other (Fig. A - Detail). This minimized the amount of toenailing, a situation in which nails must be hammered in at 45 degree angles, rather than straight on (Fig. B). The frame was assembled with 16d framing nails, as used in standard residential construction. Screws or joist hangers could also easily have been used. As a final step, we glued small "bricks" (made of 2' x 4' scraps) every 4' along the underside of the central and exterior studs (Fig. C - orange squares). This elevated the frame, increasing airflow and reducing frame-to-playa contact.

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Laying the OSB All eight sheets of OSB were placed on the frame and squared up before nailing (Fig. D).We used 8d nails to secure each sheet to the frame. The Metal Surface The eight 4' x 10' pieces of sheet metal were then laid on top of the OSB crossways and nailed in place (Fig. E). Since each sheet was 2' longer in one dimension than the OSB it covered, we overlapped the metal in the center slightly and folded the excess down the sides of the base.

Results The Domino Tower was burned on Saturday night, after the Man. Despite high winds, it collapsed as planned: one story at a time, straight down, falling entirely within the area covered by the burn shield. Despite our remote location, the resulting bonfire subsequently became the (unexpected) recipient of additional fuel from other Burning Man participants, including the BM pyro crew. As a result, it burned through the night and into the following morning. Also, due to the extremely high winds, flames from several of the burning dominoes that were toppled into the tower to ignite it were blown under the shield. This resulted in a portion of the shield's wooden frame burning underneath the metal, something that might have been prevented by shielding all four sides of the frame instead of merely two. Even so, the metal itself never burned through, significantly reducing impact on the playa and minimizing our post-burn clean up. What scarring there was occured in areas that were subjected to high amounts of heat for a long period of time. Areas of the playa that were only briefly exposed to flame - the ground beneath the burning dominoes we toppled, for example - were essentially undamaged. In these areas, clean up was often as simple as sweeping up the ash and redistributing any discolored surface dust. Alternatives & Improvements Had we not needed to build such a strong platform, we probably would have constructed an all-metal shield, using metal studs rather than 2' x 4's. Corrugated metal would also provide more insulation than sheet metal, especially if multiple layers (laid perpendicularly) were used. If cost were not an issue, more protection could be also have been obtained by making a "double-decker" shield, with two layers of framing.

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