When a free-surface gravity-driven granular flow interacts with an obstruction that spans the incident stream, it is known that a granular jump can be formed, similarly to hydraulic jumps in a supercritical regime. This paper describes a continuum model of steady jumps and propagating bores for frictional materials flowing down a slope. We investigate theoretically how the jump height can be influenced by (i) the weight and the effective friction force, (ii) the difference in earth pressure coefficients across the jump, (iii) the shape of the jump, (iv) the possible deformation of the velocity profile across the jump, and (v) the density increase across the jump. The results are systematically cross-compared to analytical solutions in hydraulics and a discussion is provided with regards to future numerical and/or laboratory tests needed.