erector started installing the purlins this week. The purlins are z-shaped steel sections that span between the beams and support the weight of the roof panels. Our purlins are a little unusual in that they pass over the beams, rather than sitting in the same plane as the beams. This, along with the use of corrugated steel decking between the purlins and roof panels, is necessary for the roof to resist hurricane-strength winds. (The corrugated decking is hiding under the blue tarp at right).