The Vancouver Art Gallery in British Columbia, Canada, has unveiled the final design for its new home, as well as announcing a CA$40m (US$29.9m, €26.4m, £23m) donation towards the CA$350m (US$261.8m, €230.8m, £201m) project.

Expected to open in 2023, the Herzog & de Meuron-designed building will be a 300,000sq ft (32,516sq m) structure incorporating 25 permanent collection galleries, with its stacked design to be built out of a mixture of glass, concrete, steel and wood. The venue will also feature a 350-seat theatre, classrooms, a library, a café and a restaurant.

The donation, which represents the largest single private donation the project has received to date, came from Vancouver’s wealthy Chan family. The gift brings total private donations up to CA$85m (US$63.6m €56.1m, £48.8m). The funding model for the new building requires a further CA$100m (US$74.8m, €66m, £57.4m) each from the provincial and federal governments, along with the remaining CA$15m (US$11.2m, €9.9m, £8.6m) from private sources.

"The new Vancouver Art Gallery will unequivocally contribute in an exceptionally profound way by providing a much-needed and purposeful venue for the arts, culture, education, community and civic life," said Chan family member Christian Chan.

"We are honoured to participate in a project that will provide such vast public benefit, while also fitting so well within our family’s inter-generational charitable mandate."

Kathleen Bartels, the gallery’s director, added: "The provincial and federal governments have been very encouraging and very supportive.

"I would really hope we can break ground by the end of this year. It just really depends when we get the necessary funding confirmations from the government."