Historic Envelope is Biggest Challenge in LEED

DALLAS—The 102,000-square foot four-story Dallas High School was built in 1907 and sat empty for nearly two decades before being purchased by Matthews Southwest. It was subsequently redeveloped into 78,000 square feet of historically converted office space, along with 10,000 square feet of restaurant, retail and outdoor patio space.

And now, the historic building has achieved LEED Gold Certification. Merriman Anderson/Architects was the design architect, historic architect and architect of record for the building shell and interior restoration, including the LEED certification process. In order to receive LEED Gold certification, Merriman Anderson implemented many sustainable site and material strategies, as well as envelope improvements to optimize energy efficiency.

“To increase the energy performance of the building, the envelope was improved per historic preservation standards, which was the biggest challenge,” said Aimee Sanborn, principal and team leader at Merriman Anderson/Architects. “However, with the envelope and lighting improvements, combined energy savings improved by more than 21.9%.”

A few sustainable site strategies included the abatement of contaminants in the existing building, installation of native vegetation with drip irrigation and priority parking for fuel-efficient vehicles as well as on-site electric charging stations. Highly reflective TPO roofing membrane, an efficient HVAC system and LED lighting were all established within the building to improve energy efficiency. With the installation of low-flow fixtures, the potable water use within the building was reduced by more than 49.31%.

More than 99.64% of the existing core and shell were reused, and products were installed that had recycled content, reducing the amount of construction waste. To improve the environmental health throughout the building, MAA installed low-emitting materials.

“Historic windows that were deemed salvageable were refurbished and reinstalled on the main elevation of the building,” Jerry Merriman, Merriman Anderson/Architects founder and president, tells GlobeSt.com. “At the historic windows, all components including the frames, sashes, glazing with divided lites and counter weights were restored. New windows were replicated to match the historic 9/1 windows. All newly constructed components match the historic characteristics. New clear, insulated glass was permitted to be installed at new windows. A mock-up of the windows was constructed and installed on site for review and approval by Dallas Landmark and Texas Historic Commission. New Schindler elevators were equipped with regenerative drives, which reduces energy consumption in comparison with conventional applications.”

LEED certification ensures electricity cost savings, lower carbon emissions and healthier environments, according to the US Green Building Council/USGBC. LEED’s global sustainability agenda is designed to achieve high performance in key areas of human and environmental health, acting on the triple bottom line of people, planet and profit.

LEED projects earn points by adhering to prerequisites and credits across nine measurements for building excellence from integrative process to indoor environmental quality. Prerequisites are required elements or green-building strategies that must be included in any LEED-certified project. Credits are optional elements or strategies that projects pursue to gain points toward LEED certification.

LEED credits are awarded by third-party technical reviewers and applicable to all building types throughout a building’s lifecycle. These credits are developed through several rounds of public comments and in collaboration with the USGBC board, broader membership and staff. As market readiness increases and new technologies become widely available, credits adapt to improve the value and environmental integrity of building projects.

Based on the number of credits achieved, a project earns one of four LEED rating levels: LEED Certified, LEED Silver, LEED Gold or LEED Platinum. The LEED rating systems work for all buildings at all phases of development and are meant to challenge project teams and inspire outside-the-box solutions.

The Green Business Certification Inc. or GBCI provides third-party technicians the training and expertise necessary to review and verify building quality and integrity.

LEED is driving international green building practices, with more than 93,000 projects participating in LEED across 167 countries and territories, and a total of 19.3 billion square feet of space used worldwide. USGBC estimates that nearly 5 million people experience a LEED building on a daily basis.

Dallas High School recently won a 2018 Preservation Dallas Achievement Award, which honors Dallas’ outstanding residential and commercial historic preservation projects, and the individuals who are committed to making Dallas a better place to live by protecting its architectural heritage.

The Merriman Anderson stamp can be seen on a wide range of project types throughout the United States and internationally. Other projects include The Statler, The Centrum, Bell Helicopter’s Global headquarters, THE DREVER and Grandscape Lifestyle Center.