Boundary-layer characteristics of a combustible along inclined hot plates are investigated taking into account the effects of buoyancy force and surface radiation. The governing equations are transformed into a set of dimensionless equations which are then solved using finite difference method. The remarkable findings are that the thicknesses of the momentum, thermal and concentration boundary layers significantly increase with increasing values of angle of inclination of the plates. For higher values of the conduction-radiation parameter, the thermal and concentration boundary layers thicken whereas the momentum boundary layer becomes thin. Numerical solutions are also demonstrated in terms of the maximum velocity and temperature. It is observed that for a greater value of the angle of inclination the maximum velocity decreases while the maximum temperature increases. In addition to, when the conduction-radiation parameter is higher both of the maximum velocity and temperature are found to increase.