The soil profile in Surrey changes abruptly from the dense glacial till under Clayton Heights to the deep, soft silts and peats along the floodplain near Bridgeview. Designing a base isolation system without mapping these transitions is a gamble. A building on the uplands might see short, sharp shaking, while one sitting on 30 meters of compressible soil in the valley experiences a long-period, amplified motion that can push an isolator beyond its design displacement. We focus on the geotechnical inputs that feed the structural model: shear wave velocity profiles, basin edge effects, and the cyclic degradation of the marine clay that underlies much of the city center. This data shapes the selection between high-damping rubber bearings, lead-rubber bearings, or friction pendulum systems. For sites with marginal liquefaction potential, we often pair the isolation design with a targeted liquefaction assessment to confirm the ground won't lose stiffness under the isolators during a long-duration subduction event from the Cascadia zone.
Base isolation in Surrey is less about the bearing and more about the soil beneath it. A 900-mm displacement rating means nothing if the foundation tilts.
