Carbondale Marketplace Development
Located in Carbondale, CO the residential component of Carbondale Marketplace Development consists of 115 apartment units, and eleven, two to three-story multi-family apartments and mixed-use commercial buildings. These buildings range from a 1,600 square foot double unit stilt structure to a 22,700 square foot multi-family and commercial building. The development also features a futsal field, a custom shade gazebo, and a community pocket park among other amenities. The location of the development next to City Market and off Highway 133 in the heart of Carbondale makes these units highly desirable.
Buildings A, B and C
Buildings A, B and C on the north are the original three-story structures with multi-family apartment units, and Building C also features commercial space on the lower level with store-front glazing. Some of the challenges associated with these buildings were the combination of wood and structural steel, cantilevered balconies, the support of two stories of brick veneer over large window openings with limited pier widths, and in the case of Building C, highly dissimilar floor plans between levels resulting from the planned mixed uses of the spaces. Foundations are conventional spread footings on the exterior with the interior demising walls being supported on thickened slabs, made possible by the excellent gravel bearing soils. Floors and roofs are framed with Trim joists, which are off-the-shelf open web trusses but with solid ends forcut to fit on site, saving vertical space for mechanical routing. In Building C, the store-front glazing on the lower level as well the two stories of brick above called for a continuous steel brick ledge with two cross-braced parallel wide-flange beams running parallel to the building to support the veneer above. While Buildings A and B used conventional shear wall paneling at all levels, the limited pier widths in Building C called for multiple braced frames at the lower level with special steel detailing to provide increased ductility in the event of seismic loading.
Buildings K & L
Two-story four-plex apartments constructed very similarly to A, B and C buildings. These are a little more private with more challenging eyebrow overhangs resolved with conventional stick framing.
Building H and J
Buildings H and J are located on the south side on the common space. These are two-story “stilts” with the lower level dedicated to parking. The parking level is framed in structural steel with exposed single brace frames in the north-south direction for lateral restraint. The exposed steel is coated with a thin film intumescent paint for fire protection. In the east-west direction, shear is accomplished through conventional wood-framed shear walls in the stairs/mechanical/storage core. Floor and wall framing is similar to earlier buildings but the roofs are single shed framed with I-joists sloping to the north side.
Buildings F & G
Next in construction are these narrow two and three-story units with jogged exterior wall lines, extensive lower level wall openings, thin brick cladding, and offset sloped roof planes. Due to concrete floor toppings, heavy exterior walls, and long east-west dimensions, the lateral design of these buildings is governed by seismic in the east-west direction. The extensive openings on the lower level north and south elevations required steel braced frames for seismic restraint. The upper levels are designed with conventional perforated shear walls. Due to fire separation requirements and different levels of framing, the common walls between units are balloon-framed and the framing levels are ledgered through continuous gyp sheathing to minimize fire-stopping. Steel connections penetrating fire assemblies are also detailed to facilitate fire-stopping.