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Abstract. Let k be a positive integer and letm be the dimension of the horizontal subspace of a stratied group. Under the condition k m, we show that all sub-manifolds of codimension k are generically non-horizontal. For these submanifolds we prove an area-type formula that allows us to compute their Q k dimensional spherical Hausdor measure. Finally, we observe that a.e. level set of a suciently regular vector-valued mapping on a stratied group is a non-horizontal submani-fold. This allows us to establish a sub-Riemannian coarea formula for vector-valued Riemannian Lipschitz mappings on stratied groups