Abstract The buildup factors of three kinds of doses were improved for two heavy concretes, one is iron contained and the other is barium contained heavy concretes. Using the data, the leakage dose distribution outside the hutch sidewall of 3 GeV class synchrotron radiation beamline and the 8 GeV class were discussed with and without the buildup effect. The attenuation of the photoneutron, which produced by the gas bremsstrahlung at the 8 GeV class normal straight section was discussed for these two heavy concretes in comparison with that of ordinary concrete, lead and polyethylene.