A method is described for calculating the electron-solid elastic scattering amplitude when the surface area covered by the coherence width of the electron beam contains a relatively small number of steps. From this it is possible to calculate in detail the angular distribution of the scattered intensity for low-energy electron diffraction. In analogy with the perfect surface case, intensity profiles are defined which characterize the variation with primary beam energy of the central intensities for the various beams. It is shown that a step distribution reduces the central beam intensities with respect to the perfect surface case and also acts to shift the Bragg peaks in the intensity profiles to higher energies. Model calculations for simple step distributions are compared with Jona's experimental data for Al(110). For many adsorbed overlayer systems the problem of domains is simply a special case of our treatment