This case study is a 12-story high RC residential building with 4 level basements.  The site is located in Taipei seismic zone 2.  The isolation layer is ground floor and the seismic layer gap is 65cm.  18 sets of High-Damping Rubber Bearing and 6 numbers of oil dampers, 100T to 200T are used.  The result of the case study shows that with proper detailing of the isolation seismic design, the performance of the isolation building is upgraded than the traditional seismic design building.