footers

I am building a 20'x20' addition for a home owner in Illinois. I have done a great deal of framming and remodel work and I need a basic cost on a foundation. It will be a four sided foundation with about four coarse of block and a footer. I would greatly appreciate any insight!! As soon as I can...

After test borings it was recommended that the footers were to be undercut 3 feet under and twice the width of the bearing concrete. It is to be back filled and compacted with 2B crushed stone. I questioned this and think that 2A or 2A modified would compact better. Should I just shut up and...