What’s leed homes all about anyway?

Houzz Contributor, designer, and LEED AP based in Northern Italy.
« The thing that’s great about LEED is that it’s a much more integrated approach to the environmental sustainability of the entire site. Passivhaus is a much higher goal than the minimum required for the energy section in LEED, but it’s limited to just that – the energy consumption as a result of the building envelope. »

Hilton Foundation headquarters yields long term value and energy savings

Accounting for High-Performance Value at the Hilton Foundation’s New Headquarters

About 30 miles to Agoura Hills, you’ll find a small office building noticeably different from the strip malls nearby. A tree-lined road leads to an architecturally distinctive 22,240-square-foot building nestled on a forested slope. Welcome to the new headquarters of the Hilton Foundation.

At first glance, you’d notice solar panels on the roof, abundant windows and daylight, and accessible natural outdoor spaces. But what really sets this high-performance building apart can’t be seen quite so literally: its high energy efficiency, pleasant interior environment for the occupants, and the substantial value it generates for the Foundation through improved staff satisfaction and work quality, and a stronger image and community presence.

Under the Surface

Conrad N. Hilton, the founder of Hilton Hotels, inaugurated the Hilton Foundation in 1944. In the years since, the Foundation has awarded more than $1 billion in grants. Today, the Foundation has 52 staff members led by their president, chairman, and CEO, Steven M. Hilton.

For decades the Foundation rented office space in the Los Angeles area, most recently in Century City. In designing a new permanent home, the Foundation’s primary goals were environmental stewardship and crafting a simple, peaceful, healthy, productive, and energy-efficient working environment that would last for at least 100 years. “The goal was not just to build a LEED Platinum building, but to control our destiny and our long-term finances,” says Pat Modugno, the Foundation’s CFO. The design exemplifies the current cutting edge of sustainability, while allowing for changes and progressive improvements in the decades to come.

The building’s LEED Platinum certification is front and center, displayed adjacent to an LCD energy dashboard that shows how the potentially-net-zero building uses (and produces) energy. The first step toward net-zero status was reducing energy consumption, to 22.8 kBtu/SF, less than one-quarter that of an average U.S. office building. A passive down-draft ventilation system that reduces heating and cooling energy by 60 percent largely made that possible: the net-zero strategy relies largely on 100% natural ventilation. A passive downdraft HVAC system uses thermal buoyancy to propel the flow of ventilation and cooling air through the building without the use of fans. Air is exhausted from the offices into a central atrium and out through digitally controlled clerestory windows.  An automatic external shade system controls direct sunlight whenever the outside air temperature exceeds 80°F.

Second, solar PV panels located above the parking area provide enough power to reach net-zero energy.

Designing a New Headquarters

The new headquarters opened in October 2012, after a design process led by ZGF Architects, who is now working with RMI on our own forthcoming high-performance building. RMI served as the primary sustainability consultant. Steve Hilton requested a highly efficient and sustainable building that would also minimally impact the surrounding environment. The entire design team, including the Foundation, held an integrative design process to find the most energy-efficient solution that preserved the natural beauty of the site. According to Steve Hilton, “usually the architect controls the design process—a very top-down approach. However, with a cutting-edge green building such as ours, everyone on the team (architects, engineers, green consultants, general contractors, landscapers, owner) contributed towards the design. A powerful synergy happens, one in which the whole is greater than the sum of the parts.”

Built at a cost of $24 million, the building has a long, narrow shape to maximize daylight gain and views to the surrounding hills. The master plan for the site includes three future buildings, all also net-zero energy, to house the Foundation as it plans to more than double in size and staff. According to the project manager, Frans Bigelow, the water, energy, and site strategies investigated can help as the rest of the site defines “the state of the art, and what limits we push when we build again.”

From the attention paid to the building (which has won numerous awards, most recently “Best Green Project” as well as the “Best Project of the Year 2013” for Southern California), you might lose sight of the fact that no matter how important the building may be, it’s the occupants that matter most.

The building efficiency movement often focuses on energy use, and how improvements can shrink the utility bill. But from the perspective of the typical owner, the energy bill is less than one percent of operating costs—more than 85 percent goes to pay the salaries of the employees in the building. When considering a highly efficient building, we often ignore all the values beyond energy cost savings, even as an increasing body of research shows that the lighting, air quality, and layout of a space can impact the health, productivity, and retention of employees.

Benefits and Challenges

At the office, Foundation staff enjoy access to nature, with gardens, excellent views of the surrounding mountainside, and even deer curious about their new neighbors. The Foundation protected more than 200 local oak trees near the building site and planted 140 more to offset the few displaced by the building. « To allow for construction, the team widened the main roadway that travels along a steep hill, creating a large amount of displaced earth. To minimize environmental impacts, crews raised the site’s existing grade by 25 ft so that the soil could be used during grading and contouring.  The project also implemented numerous land preservation strategies, including rainwater collection in an underground cistern, green roofs and native habitat restoration. Crews retained hundreds of oak trees and planted more than 140 additional trees. As part of a two-year, biologist-monitored program, an onsite plant restoration preserve was established. To ensure sustainability, the team collected seeds from native plants threatened by the new construction. They will be germinated in a controlled environment, with seedlings planted later outside the project’s footprint. »

The extensive daylighting supports this connection to nature, improves occupants’ ability to focus on their work, and provides, as Steve Hilton puts it, a “zen-like atmosphere, and a wonderful ambiance permeating the entire space.” Pat Modugno adds, “the natural lighting is a big benefit of being here; it’s very rare that I’ve ever had to turn the lights on.” Glare was initially an issue, but has been reduced through window shades, controls, and reshuffling of offices.

The office is ventilated using 100 percent outside air. These types of systems can provide superior comfort and occupant satisfaction, since the supplied indoor air is always fresh and never reused. The benefits of an effective outside air system can extend to occupant health, with studies1 showing some reduction in the frequency of respiratory infections and fewer reported symptoms of sick building syndrome. Specific data on the impact on the foundation’s occupants are not yet available, but estimates for a similarly designed office show reduced absenteeism for 60 occupants might save $11,000 per year.2

Initially the outside air system required ongoing adjustments and staff were at times too cold or too hot. According to Katherine Miller, who manages the facility, “Having ongoing support throughout the year from our project team was very important in helping to fine tune the buildings system. Utilizing data collected via the buildings management system, combined with feedback from occupants, allowed us to address seasonal changes in real time.” Despite advanced controls, variations in outside weather can occasionally require manual overrides to maintain thermal comfort.

The building’s open office plan provides for great daylight and ventilation, but it can also get noisy at times, especially for those staff that require or prefer privacy and/or quiet. To address that issue, several staff are testing variations of a sound masking system (white noise) to help improve acoustic privacy.

Overall, staff are extremely satisfied with the new building, particularly the fresh air and natural light. Organizations routinely spend on programs to retain and motivate their employees, and increasingly recognize sustainability can play a role. Conservative estimates of the savings associated with retention project more than $5,000 per year in savings for the Foundation.

The Foundation sets aggressive but financially prudent goals on energy and environmental performance, and incorporates all employees into those targets. The building has achieved most of the stated goals, saves energy and money, employees report being proud and engaged, and the Hilton Foundation is increasingly recognized as leading the way on environmental protection.

The Future

The Hilton Foundation seeks to improve the world, primarily through grantmaking, but also through responsible stewardship of resources. Highly efficient buildings are not just for nonprofits and foundations—they’re for anyone (and any business) looking to create long-term value. That value comes not just from reduced energy and water use, but from engaged, productive employees that enjoy their offices and surroundings. Increasingly, we can calculate how a highly efficient building might improve employee experiences, and add to the bottom line.


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