Blue Economy Tarp
Best bet: http://smile.amazon.com/gp/product/B0096LZRVQ/ref=od_aui_detailpages00?ie=UTF8&psc=1 60'x120' $199.00 + $25 shipping
For the temporary roof for my main house I need at least 62' x 50'.
Need to make sure the finished dimensions are actually 50' rather than just 48'.
Could use 6 mil clear reinforced polyethylene as a tarp to protect the site from rain. Americover say 6 months expected life span in fully exposed conditions. They can provide a 60.75’ x 50’ for $226.03 + shipping
Could put something over it to keep the sun off, eg old tarps, old thin planks of wood (avoid gaps), EPS for the next house level, Dupont blue roofing roll, tar paper, etc.
http://www.mytarp.com/blue-tarps-50x100-fs.aspx 50'x100' $275 + $79.77 ship
http://www.a1tarps.com/blue-tarp-50x100.html 50'x100' $280 + $120 ship
http://www.groworganic.com/blackout-poly-film-white-black-50-x100.html 50'x100' $319 + shipping
http://www.tarpsplus.com/poly-tarps-single-tarps-blue-tarps.html 50x100 $350 + shipping
If you really need bigger then it gets expensive.
http://www.tarpsplus.com/bluetarps60x100-1w90.html $420 for 100'x60' + shipping