In Milton, for example, there were the panelized shingles that allowed us to cover the barn and workshop in a matter of days, rather than the weeks individual shingles would have taken. In Watertown, the composite-frame new windows we used have reappeared in force on the current Billerica job. Their appeal is that, while they look uncannily like the real thing, they cost less and install more easily.
Roofers shuffle the shingles, made from seven different molds, to give the roof an authentic look.
This makes for easy lifting, from unloading the delivery truck to transferring the tiles to the roof to putting them in place. It also means that a standard roof structure can support them, with no special reinforcement, straps or battens. Unlike real slates, whose fragility requires extreme care in nailing, these go down with standard roofing nails, shot by pneumatic nail gun. They cut with a utility knife for fitting. All this reduces labor and therefore cost.