underpinning

by Rosettia
(Kentucky)

I need to know how many sheets it will take to underpin a 14x70 single wide mobile home. The dimensions of the sheets are 60x28 in. One end of my home is 66in (right front)from the ground...46in (right back)....(front left) 31 and the (back left)18. I tried to find a project calculator on Lowes website, but they don't have one. Please, can anyone help me?? I am a single mom with 3 kids and I need all the help I can get!

THANKS!!