A system architecture for an interior putty applying robot is presented in this paper. In order to adapt to the complex scenes on the construction site, the robot is required to have a flexible movement space and the ability to interact with the external environment to protect surrounding objects and the robot itself. Therefore, a 9 degree of freedom(DOF) redundant robot consisting of a 6 DOF series robot and a 3 DOF parallel robot is designed in this paper to achieve a flexible motion space. The gradient projection algorithm and the weighted matrix are used to ensure the reasonable distribution of joint motion. At the same time, a compliant end effector(EE) based on an impedance controller is designed to respond to external environmental interactions and improve the smoothness of putty applying. Finally, simulation and experimental results verify the feasibility of redundant robot kinematics algorithms and compliant EE.