HOK’s LEED Platinum Houston Office Supports Integrated Design in High-Performance Space
HOK’s Houston team designed its new 35,000-sq.-ft., LEED Platinum office to promote health and wellness while encouraging collaboration.
In deciding to leave the 64-story Williams Tower in Houston’s Uptown District, leaders of HOK’s Houston practice determined that they wanted to move away from a traditional center-core office layout. Instead, they set out to create a workplace that accommodates open offices and collaborative studio space for multidisciplinary design teams. In addition to supporting integrated design, the team wanted to use the renovation to showcase the high-performance, sustainable design that HOK offers clients.
The new space takes up the ninth and 10th floors of the 1984 Phoenix Tower in the heart of Houston’s Greenway Plaza. In 2011, the building received Gold certification in the U.S. Green Building Council’s LEED for Existing Buildings: Operations and Maintenance rating system. HOK’s interior fit-out for the space recently earned LEED for Commercial Interiors (v2009) Platinum certification.
The space fosters creativity while encouraging interaction, collaboration and comfort. By making major changes to the base building structure and circulation systems, the design team converted two previously separate floors into a two-story space that allows all occupants to experience open space, daylight and views to the outdoors. The design raised the ceiling from 9’-6”-high to 26’-10” at its highest point, with 12’-10”-high curtain wall. A new open stairway connects the previously separated floor plates.
The open office space provides a variety of workspace options, including bench seating, sit-stands and informal meeting areas. Huddle and focus rooms are available for small groups and individuals. With a “yours to ours” approach to the workplace, the design reduced the average personal space from 66 square feet per person in the previous space to 38 square feet in the new office. Shared space increased from 18 square feet per person to 34 square feet. Eliminating private offices further encourages collaboration.
A design lab—a large, open space with a material library and product display area—hosts office and community events. Separated from the main office space, a break area offers the atmosphere of a living room with a large communal table, informal sofas and a TV. Views toward downtown and an adjoining terrace garden, a building amenity open to visitors and building occupants, link people to the outdoors. The museum-like entry, featuring rotating artwork by local artists, creates a design-focused atmosphere to welcome building visitors from the sky lobby. A window provides views into the studio’s model shop.The integrated sustainable design strategies improve employees’ comfort, health and wellness in a highly sustainable, LEED Platinum workplace.
To conserve water, the design team worked with the building owner to upgrade the core and shell restroom fixtures on the ninth and 10th floors to more water-efficient models. Using high-efficiency, low-flow fixtures and fittings achieved a 40.93 percent water use reduction.
Energy and Atmosphere
Focusing on elements of the tenant fit-out that they could control, the design team incorporated sensible, cost-efficient strategies to improve energy efficiency.
HOK worked with the building owner, Parkway Properties, to install an automated shading system. Radiometers installed on the building’s roof feed detailed information on the sun’s position and the location of cloud cover to an automation system that adjusts the shades. The lighting system then automatically adjusts to the amount of ambient daylight in the space. Nearly every occupant has access to high quality daylight and direct views to the exterior. Future tenants of Phoenix Tower will be able to use the radiometers for their own shading systems.
Automatic occupancy sensors monitor 100 percent of the space and daylight harvesting controls are installed on most of the lighting fixtures within 15 feet of a window. Field relay and low voltage switches are provided for each open and enclosed space. All lighting fixtures in conference rooms are dimmable. Through smart lighting design and the integration of high-efficiency LED fixtures, the project achieved a 35.75 percent reduction in connected lighting power use compared to ASHRAE 90.1-2007 standards.
Because the project uses an existing base building HVAC system, the team paid special attention to installing appropriate zoning and controls in the space. The design team increased the number of temperature zones over the base building standard to better satisfy the functional needs of the program, boost occupancy comfort and improve energy efficiency. Temperature setpoints are locally adjustable by occupants within prescribed limits.
The team specified 100 percent ENERGY STAR-labeled products for all new appliances and equipment purchased for the space. The project includes sub-metering equipment to measure and record energy consumption within the tenant space.
The design replaced outdated pneumatic controls with more energy-efficient and reliable direct digital controls. Controls are programmed to satisfy control sequences of operation unique to the needs of the areas served.
Renewable energy credits were purchased to offset the office’s electricity use for two years.
Materials and Resources
The project scope included the demolition of existing space on the ninth and 10th floors of Phoenix Tower. The team collaborated with the general contractor to create a waste management plan. Over the course of the demolition and construction phases, 92.9 percent of the total waste generated was diverted from a landfill and recycled.
A significant amount of existing furniture was reused for the new space. When possible, the design team incorporated regional materials with a high percentage of recycled content.
Indoor Environmental Quality
The team used robust strategies to improve the indoor environmental quality and to minimize exposure to particulates, biological contaminants and chemical pollutants. Low-emitting materials were used for all adhesives and sealants, paints and coatings, flooring systems, composite wood and agrifiber products, and systems furniture and seating.
The project design provides access to daylight and quality views for its occupants. MEP systems promote good outdoor air flow and thermal comfort for all occupants.
Prototype for a Sustainable Gulf Coast Interior Fit-Out
The project is a prototypical example of climate-appropriate design for a high-performance interior fit-out in the Gulf Coast region. The design team focused on strategies within the scope of the project that they could influence, such as automated sun shades, daylight harvesting, lighting efficiency and the use of energy-efficient equipment.
HOK’s Houston team provided project management, interior design, architecture, sustainable design and LEED management, MEP engineering, structural engineering and visual communications services. Balfour Beatty Construction was the general contractor.