The project is the first multi-story office building in North America to employ dowel laminated timber (DLT), a mass timber system relying on a friction-fit bond between softwood dimensional lumber and hardwood dowels. The 65,000-sf building anchors a high-visibility 265’ x 65’ site two blocks from the river. Retail spaces activate the street level with three floors of office space above.
Spruce glulam beams and columns frame the 40’-0” x 6’-8” DLT panels that serve as floor and roof decks. The system facilitates quick erection time and a smaller site crew, minimizing disturbance to the neighborhood during construction. A precast concrete service core buttresses the south of the building functionally and structurally.
The wood construction’s refined aesthetics enable the structure to remain exposed as an interior finish. This minimizes tenant improvement work and the potential for chemically impregnated finishes while providing visual, tactile, and olfactive stimulation to its occupants. Operable windows within each structural bay allow natural ventilation. Balconies on the west take advantage of downtown views. Natural Accoya wood soffits and columns complement the exposed wood interior. Black Zalmag panel rainscreens clad the east, north, and west elevations.
The project is innovative in both design and project delivery. The core design team of architect, civil engineer, and structural engineer collaborated closely with the mass timber engineers and general contractor from the onset of the project. This relationship enabled the project to push the boundaries and convey the accessibility of a sensible material.
111 East Grand, LLC
Des Moines, Iowa