This architecture is inspired by the city’s classic steep-roofed shapes, which are interpreted in finely detailed modern materials done by Warren and Mahoney-designed luxury apartments crafted by Summitbuild. Due to a limited amount of working space on a busy street, prefabricated XLam panels were an obvious option for construction.
Structural system
The entire building structure above the ground floor slab comprises XLam CLT, with some integrated steelwork. Walls are generally 3-layer 75mm thick panels, doubled for inter-tenancy acoustic separation. A Drossbach-type connection system was used at ground floor level, with walls pre-drilled in the factory to receive steel dowels cast into the concrete slab and then epoxy-glued to the timber. XLam TwinSkin cassette floors span up to 5.6m. TwinSkin roof panels incorporate factory-installed thermal insulation within the panel cavities, giving a high R-value and greatly simplifying installation of the zinc-clad roof structure.

Source: https://www.xlam.co.nz/case-studies/salisbury-street-executive-apartments.html