I recently excavated out a section of my basement so I could redo the drain tile and at the same time put in a walkout basement. My understanding is that I need to put in a frost wall 4' below grade. Is there anything more to the frost wall than brick and mortar?
My plan: pour in a footing, lay 8x16x8 brick with mortar up to the foundation (underneath).
The frost protected shallow foundation that Steveel linked to might be a good option for you if your basement will be heated. You basically insulate the outside of your existing foundation so it won't freeze/heave.