In one aspect, the invention provides a photovoltaic roofing element for disposal on a roof deck. The photovoltaic roofing element includes a roofing substrate including a top end and a bottom end. The roofing substrate includes an upward-facing zone having an upward-facing surface and a bottom end; a lateral flexible zone extending adjacent the bottom end of the upward-facing zone, the lateral flexible zone having a bottom end; and a strip of material disposed at the bottom end of the lateral flexible zone having a first surface on the same side of the substrate as the upward-facing surface and a height of at least about 1 cm as measured along a line from the top end to the bottom end of the roofing substrate; and a photovoltaic element disposed on the upward-facing surface of the upward facing zone of the roofing substrate.