Is this a full structural wall or just a couple courses of brick veneer?

Dick

The below grade stem wall steps from 10' below grade to 4' below grade.  The stem wall supports two stories of load bearing cavity wall (brick, insul., air space, block).

These are relatively common in Ontario and foundation wall construction typically has parging on the surface and the mortar joints are struck flush and waterproofing/dampproofing.   If drainage to one side, then often a mortar/concrete 'wash' is constructed on the footing...

Dik

I assume your two stories of cavity wall are either 6" or 8" concrete masonry, a cavity with insulation and then the brick.

Make sure you have proper flashing including weeps to provide an exit for any moisture that may be in the cavity.

Dick

CAvity wall construction details are all right.  I want to know of anything required below grade for double wythe masonry construction.
Tie the units together?
Grout between the units?
Anything else?

ACI 530 gives the structural requirements for tying the mutiple wythes together.

I assume you will try to use a single wythe reinforced concrete or a block wall wherever possible to be the most efficient. You cannot the use the brick veneer of the cavity wall as a load bearing component in the wall. One you fill the "collar joint", you not longer have a cavity wall with insulation.

If you are using an empirical design, you will be limited to a single wythe hollow or solidly grouted wall as the structural wall in those portions.

For allowable stress design, the back-up is the the structural element and the brick is a non-bearing veneer.

For information on all types of concrete masonry degign, the National Concrete Masonry Association (NCMA.org) has a comprehensive series of TEK Notes that are periodically updated to match most code changes. The TEKs also contain many good details.

Go to the NCMA site, click on TEK notes and then just indicate what state or supplier you may be near. The TEKs are in .pdf format and are written by engineers that are very active in all the code organizations and operate a fine lab for research.

This is a well-hidden resource that has substance and continuity.

I will suggest to fill solid your cavity underground and place your flashing to drain above ground, this will keep all moisture above ground and drain to the exterior through weephole