b'polar coordinate system. We would use what was to be theMore corners equals more cost is the conventional center of the spiral staircase as the center of a 360-degreewisdom of the building trades. With fifty-two walls, cutting Blue Maxx Up Closeradial grid and let the spiral find itself on the grid. Insteadthe corners would have been an exacting, labor-intensiveYou can see from the photos on these two pages that the Blue of measuring angles (difficult to do precisely), we wouldtask in wood (whether post and beam or the wood formsMaxx system we used is like a life-size Lego set, with a functionality that especially suited our idiosyncratic design.measure the radiusthe distance from the center to everyused in traditional concrete building). With Blue Maxx,Each Blue Maxx block is actually two polystyrene panels separated point where two walls intersected. So we went back andwe could cut the corner blocks with a utility knife, and weby hard plastic spacers (facing page top right). calculated every center-to-angle radius in the plan. Thencould do it fast. And unlike the plywood forms used inRebar inserted in the space between the panelsvertically and horizontallyadds strength and a unifying framework; concrete when we laid out the footings and raised the walls, we usedtraditional concrete structures, which are discarded, theis poured to fill the space. (See the two photos at left.) The foam a transit to precisely measure that specified distance fromBlue Maxx foam blocks stay in place, providing insulation,panels insulate the concrete as it cures, so it hardens slowly, making it much stronger than concrete poured in a traditional wood form. the center to every angle. It seems so obvious in retrospectfireproofing, and vapor barrier.Even so, we used a very strong concrete, something like four thou-except our thinking was conditionedand blindedsand pounds per square inch. With twelve inches of reinforced concrete and Blue Maxx, covered with four inches of stone on one by the traditional construction parameters of rectilinearside, our walls are about sixteen inches thick.space. What I especially loved about the solution is that theFor the subterranean basement (below left), we covered the Blue Maxx with cement block, sealed it with tar, added a waterproof insight is metaphysical as well as geometric: the importancemembrane, and backfilled against that. The cement block provided of the center, and the need to return to it as a touchstonethe building ledge on which the ground-floor veneer would rest.throughout the journey.Above ground (below right), we covered the wall forms with a vapor barrier consisting of a plastic membrane with a waterproof cloth backing. Any moisture that gets through the stone travels The Blue Maxx Wall Forming System down the membrane and ultimately out the weep holes near the base of the wall. Theres no opportunity for water to pool behind Imagine two-and-a-half-inch foam blocks that fit togetherthe veneer or be diverted into the wall or the house.almost as easily and flexibly as Legos, reinforced with rebarGalvanized metal strips serve as wall ties that literally tie the veneer plane of stone to the concrete-filled wall form so the two become and then filled with concrete. Thats the Blue Maxx wallone. (Those strips are visible in many of the photos here, but espe-structure that holds four stories of stone veneer inside andcially the one below right and also on the following spread, bottom right.) The wall ties screw into industrial strength plastic strips that outside the Spiral House.are part of the wall system, and then fold down into the mortar 143between courses of stone. Without the wall ties, the veneer plane would be a four-story wall of stone that could fall forward and separate from the structural wall.'