I have been asked to bid an option for shallow frost protected footings. We have done them before and I know how to, but how do I design them to meet IRC 2006?

Brad,
Here in CT the air freezing index is 1500 or less and according to the design guide for frost protected shallow foundations second edition we have a minimum footing depth of 12 inches. My engineer uses 16 inches as a minimum. Here is a link to a video that simplifies the job.    thefootholdicf.com

I don't know the needs here, but consider a frost protected, thickened edge, monolithic slab instead of footings.

Try enerSLAB. Engineered raft slab can be s
Designed to bear in soils as low as 700 psf. Very quick and easy to install and compliments iCF or any other construction type