GEM, and with that CRCM-GEM is , are using both , horizontal and vertical staggering.
In the horizontal, the Arakawa-C grid is used. In the vertical, the Charney-Phillips grid - see graphic below.
The winds horizontal wind components are on the full levels, also called "momentum levels" and the scalar fields (like temperature, humidity, hydrometeors and other passive tracers, ) as well as the vertical velocity ) components are on the half levels, also called "thermodynamic levels". The They are alternating with the lowest atmospheric model level being a thermodynamic level , and the highest being a momentum level. See also the wiki page about model levels.
For more information, have a look at the following publication:
Girard, C., A. Plante et al., 2014: Staggered Vertical Discretization of the Canadian Environmental Multiscale (GEM) Model Using a Coordinate of the Log-Hydrostatic-Pressure Type. Monthly Weather Review, DOI: 10.1175/MWR-D-13-00255.1