Commercial Construction & Renovation helps our subscribers design, build and maintain better commercial facilities by delivering content to meet the information needs of today's high-level executives.
Issue link: https://ccr-mag.epubxp.com/i/666154
74 COMMERCIAL CONSTRUCTION & RENOVATION — MARCH : APRIL 2016 PUSHING THE ENVELOPE Adam Petersen is a senior project manager for R&H; Construction, an Oregon-based general contracting frm that has been building successful commercial construction projects throughout the Pacifc Northwest since 1979. For more information, visit www.rhconst.com It was important to the developer to know precisely where the siding material was coming from, reaching beyond FSC and SFI certi- fcation. Additionally, second growth wood was intentionally chosen because of the negative environmental impacts of using old growth cedar, a rare species in the Pacifc Northwest. The trees for the second growth western red cedar siding initially were sourced through Wetset Enterprises, a member of a co-op of private landowners in Western Washington, Northwest Resource Group. This unique group of landowners manages their forestlands sustain- ably, and was willing to work with the project team on a custom spec- ifcation for the buildings' cedar siding. R&H; was able to hand-source domestically harvested non-old growth cedar, meet the individuals logging and milling the material, and run a custom 5/4-inch profle for increased durability. As one of the most sustainable features in the building, it also proved to be one of the most challenging. Maximizing return Every design aspect of One North was intentional, and each feature and product was carefully weighed against a single overarching goal: to use systems and approaches that could serve as a model for future projects. This required taking a critical eye toward sustainable practices in order to fnd the balance between green initiatives and not diminishing return by adopting excessive sustainability standards. With the developer and Holst Architec- ture, R&H; carefully weighed the options to see which products would achieve the project goals without unnecessary spending. One example that demonstrates these efforts presented itself when considering a curtainwall versus storefront system for the windows. The frst was more appropriate for air and energy performance, and the higher expense was warranted for the long-term energy savings. When evaluating double-glazed versus triple glazed units for windows however, the performance increase was almost negligible – but the cost differentiation was astronomical. Therefore, the team deemed triple glazed units unnecessary for the project, and opted to use double glazed instead. To maximize the energy effciency of the shell, the buildings feature a double paned thermally broken curtainwall system on all foors, 8-feet of dense pack cellulose insulation in the wall cavities and 4-inch mineral wool exterior insulation as part of the rain screen. The thermal separation is carried down into the subgrade as well with two inches of rigid insulation underneath and fully encompass- ing every exposed footing, slab, and stem wall that would traditionally come into contact with the earth. A custom 2-inch thick as-cast architectural concrete panel was poured in front of the insulated stem walls to achieve the desired aesthetic and maintain the thermal separation, for signifcantly less cost than a more typical pre-cast concrete solution. Rather than seeking third party recognition of sustainability efforts for the project, Lemelson had his own interpretation of the level of excellence the project would achieve. Heightened standards for energy performance, ethical practices and a commitment to building with the greater North Portland community in mind each contributed to this sustainable, lasting development. The future of commercial building While tracking the momentum and innovation surrounding green building trends, the leaps and bounds of progress made is inarguable. Yet it also begs the question – where are we going next? The defnition of sustainable con- struction ultimately is at a tipping pointing, and the values that drive that mission will continue to evolve as we look at the bigger picture of what impact truly means – in the community, on the environment and relating to sustainability. By focusing on how all of these components ft together and taking a more critical eye toward the design and construction process, we truly can begin to redefne what it means to build to a higher standard. CCR One North is meant to serve as an example of the approach to commercial buildings in the future, and the use of prefabricated materials and other features helped improve effciencies and cut costs.