Do any of you have experience in foundations?

I'm adding a timberframe addition to the back of my house. My current house is built on a slope so i have a walk in basement in the back. Due to the slope, the entire addition will be above grade with the basement floor on grade.

Due to this configuration, i'm considering pouring piers to below the frost line (NorthEast) at all post locations and then pooring a slab for a basement floor. This would be instead of a continuous frost wall.

Any comments or suggestions?

A continuous frost wall is the way to go. It keeps critters from burrowing under the slab, gives a solid base to the wall and if insulated it will help keep the soil warm under the building. Talk to your local building department regarding the energy code for insulation requirements. I have worked on jobs where it was priced both ways and the frost wall has always been chosen for the small additional cost.

Thanks for your input, Christopher.