The structure of a new wall system was that of a three-layer sandwich-type panel with external/internal layer consisting of shape-stabilized phase change material (SSPCM) wallboard and middle layer consisting of conventional concrete. The external layer was active in hot seasons and the internal layer was active in cold seasons. An office room integrated with the novel double SSPCMs wallboard with a splitting air-conditioner was used for modeling and simulation test platform. Studies were conducted to investigate the effects of the novel double SSPCMs and different parameters on the energy and thermal performance in typical climate area with hot summer and cold winter (Wuhan city, China). Test results showed that the recommended thicknesses of external and internal SSPCM wallboard were 30-60 mm. With the recommended thickness, the annual energy savings for cooling were 3.4-3.9%. The peak load reductions for cooling were 3.1-3.8%. The annual energy savings for heating were 14.8-18.8%. The peak load reductions for heating were 8.6-11.3%. The external layer was effective on reducing annual energy demand and peak load of cooling in hot seasons. The internal layer was effective on reducing the indoor temperature fluctuation in cold seasons. (C) 2015 Published by Elsevier B.V.