Base Isolation

Base isolation is a technique invented in Wellington by Bill Robinson to minimise damage to buildings during an earthquake.

How base isolation works

Base isolation involves putting flexible bearings or pads made from layers of rubber and lead between the building’s foundations and the structure above. These base isolators move and stretch under pressure and absorb much of an earthquake’s impact by reducing swaying and shaking during an earthquake.

Diagram of seismic isolation plate showing the position of base isolators.

Other buildings and countries that use base isolators

Some examples of buildings that have base isolators in Wellington are:

  • Wellington Central Police Station
  • Parliament
  • Parliamentary Library
  • Old Bank Arcade, Lambton Quay
  • Wellington Hospital main building
  • Te Papa (where you can see how base isolators work).

Today in New Zealand, about 40 buildings have base isolators. Overseas, they are used in Italy, Oregon, California and Japan.