if you make the frame from wood, you lock up carbon. steel is a total waste of resources, also conducts lightning through the frame of the building.
plastic is the worst possible choice for the panels, almost anything else is better, as long as it is reasonably fireproof.
sometimes long life is a bad thing - plastic is damned hard to keep clean, and harbours disease - it would be far better if the panels were made of something local, cheap and recycleable, that needed to be replaced at least yearly.
with a little bit of careful thought, just about any country could produce it's own emergency shelter system out of local resources.
funny how the western world becomes less and less competent at anything, the fatter and more ikea it gets.
these people should give up saving the planet, and learn how to feed their own children properly, they are becoming as dumb as the cows that seem to be the only thing they eat.