Platte Fifteen: Beautiful from Top to Bottom
WORDS: Sean O’Keefe
Nature has a way of absorbing differences between people – a passive, smoothing constant that seems vitally inherent to what it means to be natural. The warmth of the sun, the whisper of the wind, the cool of a breeze, the essence of nature is both ethereal and tangible. As structure, purpose and possibility continue to evolve in commercial building construction, savvy developers have come to recognize the need and benefits of integrating nature’s regenerative powers into the places we live, work and play. Harnessing the power of nature through sustainability and Craftmanship, Platte Fifteen has arrived as a pioneer of progress with a new take on old means.
“As developers, Crescent’s objectives are to create buildings that add value to communities and customers today and many, many generations into the future,” says Conrad Suszynski, co-CEO of Crescent Real Estate LLC. Suszynski and the Crescent team’s latest contribution to community comes in the form of Platte Fifteen, a 156,915-square-foot mixed-use office property that now commands attention at the corner of 15th and Platte streets just west of the confluence of Cherry Creek and the South Platte River. “The common connection between our developments is that we seek special locations and strive to create buildings that can’t be easily replicated or replaced.”
At a glance from the street, the sleek glass and brick edifice is proud and elegant yet at only five stories tall seems a willing transitional figure between neighborhood and city. A hidden gem and something of a first, only upon entry does Platte Fifteen’s unique character begin to reveal its true natural splendor.
“Exploring the use of mass timber is great environmentally and creates wonderfully warm, natural, biophilic spaces that enrich human experiences,” says Suszynski. “It may not be best for every location or product type but here mass timber is fundamentally what makes this building special.”
Modern mass timber is made from young, sustainably harvested trees. Early growth trees are cut into strips of wood that are laminated together at alternating angles to form a reliable, high-density composite. The finished block of wood is every bit as strong as the heavy timber logs commonly used as structural columns before the mass production of steel but is derived from young, easily replenished trees. Structurally, the finished members retain the strength of steel yet are five times lighter than concrete.
“In partnership with OZ Architecture, Crescent has been expanding our understanding of mass timber through a series of projects, stretching back to the Loading Dock in Boulder,” shares Suszynski. There, mass timber was integrated into the walls, floors, and structural columns of a 36,000-sf office development. At Platte Fifteen, mass timber is fundamentally the basis for the building as well. Coordinated correctly, mass timber offers a single-source structural solution composed of prefabricated columns, beams, walls and floors that are manufactured off site in controlled conditions and then assembled akin to building blocks on site.
“Modern mass timber presents an opportunity to push design beyond previous precedents, to build better,” says Joe Anastasi, project architect with OZ Architecture. Like many in the field, Anastasi thrives on a good design challenge and in this case believes in mass timber’s capacity to deliver a unique solution and experience. The challenge for designers and builders, of course, is using the innovative material in a way that delivers the premium, modern, city-worthy wow-factor architecture the site commands at a cost and schedule that competes financially with concrete and steel.
“The solution to the cost component is holistic,” says Suszynski. “From site orientation to connection points, OZ, KL&A and Adolfson & Peterson Construction considered every detail and dimension searching for efficiencies until no stone was left unturned.”
The realized vision for Platte Fifteen begins with old development wisdom, that if quality is created at an exceptional but underutilized location, achieving profitability is well within reason. Making the proforma work at Platte Fifteen came down to column placement, simple solutions and elegant details. A modern office building in steel or concrete delivers a 30-by-30-foot grid of open span office space. This spatial freedom allows owners to easily partition floor plates into various configurations initially and flexibly in the future.
“The design challenge was in planning a modern office in this 30-by-30-foot grid spacing as efficiently as possible, in a material that was assumed to be more expensive,” says Anastasi. He points out that occasionally, choosing a more expensive component can drive substantial savings in labor or ancillary systems. Only through a comprehensive team preconstruction effort can mass timber’s cost competitiveness be realized. Despite the shared success on the Loading Dock, on Platte Fifteen, initial costing came in approximately 15% over budget – a delta tied in many ways to unfamiliar means, methods and materials. The entire team came together to solve equations like how to decrease the number of structural connections or simplifying the design and fabrication of attachment components to assemble the structure.
“Our responsibility is to analyze each factor that should be considered and deliver these in a way that allows each discipline to make easy decisions,” continues Anastasi. “Working with each consultant, Adolfson & Peterson Construction and with Nordic, in an integrated design approach, the team collaborated thoughtfully and holistically on how each decision impacted cost and the final product.”
Taking cues from the activity fostered by revitalized surroundings, the building deftly mixes brick and transparency in a modern interpretation of the historic streetscape. A retail wrap along the base is tucked beneath a covered paseo, ensuring the energy of Platte Street turns the corner. Window patterns derived from studies of neighborhood buildings are punched into the hand-selected red brick, subtle nods to context that enhance presence by acknowledging place.
As Platte Fifteen’s first tenants arrive this spring, the building readies for the day-to-day realities of being a working member of the community. Crescent is already putting pen to paper and concept to calculator on the lot across the street; a property they own and plan to develop as mixed-use office and retail. Asked about what makes Platte Fifteen a distinct presence in Denver’s ever-growing tapestry of in-fill architecture and Suszynski shares multipronged confidence.
“People working here will enjoy a warm inviting atmosphere naturally enriched by the use of mass timber, but that is hardly even the beginning of the sustainability story,” says Suszynski. “This building will actually store 1790 metric tons of carbon dioxide within the wood. Another 3,800 metric tons of carbon dioxide greenhouse gas emissions will be avoided for a total potential carbon benefit of 5,580 metric tons. In short, we have proven that wood is a cost-viable, sustainable structural option with regenerative benefits for mid-rise commercial construction. That’s a genuine evolution, that’s a big deal.”
Published in the March 2020 issue of Building Dialogue.