Roof tiles and roof tile structures

A roof tile, a multiplicity of which, when nested in an overlapping relationship to one another, provide a membrane for overlaying and protecting a roof structure comprising:

• a foam core member having a first edge, a second edge and a plurality of longitudinal surfaces there between including an upper surface and an opposing, spaced apart, lower surface wherein said upper surface and said opposing lower surface include an arcuate section said upper and lower surfaces of which are substantially the same size and shape between said first and second end edges;
• a cement-based protective coating covering at least said upper surface and said lower surface of said arcuate section wherein said upper coated surface of said arcuate section is substantially the same size and shape as said lower coated surface of said arcuate section,
• whereby when said roof tiles are disposed in an overlapping relationship, and said lower coated surface of said arcuate section of one roof tile is disposed at any longitudinal location onto said upper coated surface of said arcuate section of another said roof tile, substantially the entire said upper and lower surfaces of said roof tiles of said arcuate section will be in contact where they overlap.