The structural system for this building consists of a precast concrete podium supporting four levels of conventional wood framing with a flat wood roof. Beneath the podium, there is one level of partially below grade parking with a slab on grade and masonry foundation walls. In addition to 54 residential units, building amenities include a 2-story entrance lobby, fitness room, and a club room leading out to a large wood-framed deck.
A unique structural aspect of this project involved a tall site retaining wall on the south side of the building near the lake and wetlands. Due to site constraints and the retaining wall’s proximity to the building foundation walls, it was necessary for the retaining wall to tie into the adjacent foundation wall for support. BKBM worked in collaboration with the site retaining wall engineer to coordinate connection details and additional retained soil loads that the building foundation wall needed to be designed to resist.
The project is located on a 3.24-acre parcel adjacent to Glen Lake. Some civil design challenges for the project include approximately 26 feet of elevation change, existing wetlands, and large mature basswood and oak trees located on or near the property line. In addition, the local watershed district has robust stormwater runoff requirements the site needed to meet, and the City requested public trail access to nearby Kinsel Park. To meet the design goals BKBM placed a series of retaining walls and switchback walks to incorporate the elevation changes. The site retaining walls were also used to define the two infiltration treatment ponds located on the lower end of the site, adjacent to the wetland buffer. Additional erosion control mat and double rows of silt fence were used during construction to protect the buffer and wetland. Permanent erosion control mat was added during final stabilization to provide long term protection to the site soils. BKBM also worked with the site landscape architect to establish perimeters for tree protection and standards for proactive pruning of trees that may be affected by construction.