For turbine generated building vibration used in wind power industry, estimation of excitation/contact force at the connecting point between turbine and building structure is one of main concerns for Lab simulation of turbine. However the Lab simulation method aiming at achieving both accurate simulation of working environment of turbine and the corresponding vibration level prediction/quantification of building response is not available so far. The direct force measurement method was investigated and found to be practical impossible in terms of operational accessibility. In this paper a method for indirectly determining interface contact force is proposed for Lab simulated, motor replaced, free stand wall mounted building vibration prediction. Power supply for driving the turbine and rotational speed automatic control of turbine for Lab simulation were determined by the proposed method. Furthermore, the establishments of suitable FEMs with their validation achieved good prediction results within acceptable error scales.