Sarjeant Gallery: Checks on historic building's movement proves solid design 2 Mar, 2021 04:00 PM 3 minutes to read A new concrete retaining wall installed behind the Sarjeant Gallery prevents subsidence during construction of the extension wing. Photo / Supplied Whanganui Chronicle By: Project Director Gaye Batty Systems are in place and regular checks show no significant movement of Whanganui's 100-year-old Sarjeant Gallery, now in the full swing of redevelopment. The Sarjeant Gallery redevelopment project involves earthquake-strengthening of the existing heritage building and construction of a new wing – Pataka o Sir Te Atawhai Archie John Taiaroa, named in honour of the much loved Whanganui kaumātua.