While still fussing--- endlessly, it seemed --- with the vent, I lost patience and decided that I simply HAD to get some glazing up, to assure myself that this was, indeed, going to be a greenhouse. The roof has to be glazed first, of course, so we started on the other side from the vent, and put up several sections. They looked wonderful! So the next work day, having finished with the @#$!%&*! vent, we went ahead and finished glazing that side of the roof. I was overjoyed, until I realized that I had forgotten to install the cames. These are horizontal bracing bars that are fastened to the inside of the polycarbonate sheets by screws and rubber-bonded washers from the outside (and I have no idea how they came to be called cames).

My dismay at this oversight stemmed from the fact that with the glazing up, we couldn't work from the inside to screw down the cames, and working from the outside demanded a lo-o-ong reach. I called in another helper, 6'4" tall, who laughed as he drove the screws in, hardly stretching at all. In my frustration at forgetting about the cames, I half-considered leaving them off: the large, uninterruped expanse of polycarbonate was so beautiful. But then a gust of wind blew in and I saw those beautiful panels of polycarbonate belly up in the middle, and hurried to get the cames in place.

Actually, I needn't have fretted about forgetting to install a came with each panel of glazing. Getting them aligned was enough of a challenge after the glazing was in place, and it would have been almost impossible to do piecemeal.

Here's a portion of the roof on the vent side. The diagonal white pieces are the bar caps that hold the glazing in place; the black line along the edge of each bar is the rubber gasket that compresses against the polycarbonate to provide a seal. (At this writing, we haven't had a drop of rain for six weeks, so I have no idea how good the seal is. Sprayed on water from the hose, but of course that's not quite the same as a good downpour.)

The button-like things in the picture are the washers and screws that attach the cames to the inside surface of the glazing.

With the roof glazed, we were eager to complete the transformation of the aluminum skeleton into a greenhouse . . . .