standing seam sheet is snap locked into the other standing seam sheet that is fastened to the roof, concealing those fasteners, and the other side of the sheet is fastened to the roof with screws, and the next sheet will cover those screws as well. The fastener screws shouldn't be screwed in to tightly to allow the sheet to expand and contract with the changing temperatures, each fastener slot has some room to move past the screw to adjust for thermal expansion. The fastener heads breaking off potentially is the down side to this method if installed improperly or from wear and tear from the fluctuating climate. Snap locked with clips Snap locked with metal clips fastened to the roof allows for more thermal expansion than fastener strip standing seam metal roofs. The fasteners and clips are both hidden under the metal roof sheets, and this option is marginally more expensive than the fastener strip snap locked standing seam roof. Thin film solar on metal roofs With the increasing efficiencies of thin film solar, installing them on metal roofs has become cost competitive with traditional Monocrystalline and Polycrystalline solar cells. The thin film panels are flexible and run down the standing seam metal roofs and stick to the metal roof with Adhesive, so no holes are needed to install. The connection wires run under the ridge cap at the top of the roof. Efficiency ranges from 10-18% but only costs about $2.00-$3.00 per watt of installed capacity, compared to Monocrystalline which is 17-22% efficient and costs $3.00-$3.50 per watt of installed capacity. Thin film solar is light weight at 7-10 ounces per square foot. Thin film solar panels last 10-20 years but have a quicker ROI than traditional solar panels, the metal roofs last 40-70 years before replacement compared to 12-20 years for an asphalt shingle roof. Corrugated metal roof corrugated metal roofs are prefabricated sheets that are bent and wavy to make them more rigid. They are similar in price to asphalt shingle roof installation. The fasteners are screwed through the metal into the roof requiring more maintenance to make sure the screws stay secured. corrugated metal roofs can last 30-45 years with proper maintenance. Stone-coated metal roofing Metal tile sheets can also be employed. These are usually painted or stone-coated steel. Stone coated steel roofing panels are made from zinc/aluminium-coated steel with an acrylic gel coating. The stones