A commercial real estate developer is at odds with a development authority in Hawaii over the glass used in one of its high-rise projects.

Rendering of the Symphony Honolulu building, via Oliver McMillan
Rendering of the Symphony Honolulu building, via Oliver McMillan

The Symphony Honolulu mixed-use condominium tower is under construction in the Kakaako district of Hawaii, where new construction high-rise projects require glass with a visible light transmission (VLT) of 50 percent or greater. The glass being installed on the project has a VLT of 28 percent, though the developer insists that the glazing was selected in accordance with the area’s green building rule and can’t meet both.

In February, Oliver McMillan Pacific Rim (OMPR) received a notice of violation from the Hawaii Community Development Authority (HCDA), and the sides continued their exchange for the next few months. OMPR requested an administrative review process for the rule because it prevents projects from meeting minimum energy requirements mandated by the HCDA.

Public hearings were held in July and August, but the HCDA failed to come to a decision in the most recent hearings and will continue the hearing on September 2, according to the Pacific Business News.

In the meantime, OMPR put its proposed findings of fact and conclusions of law before the HCDA. The developer notes that the glass rule was created in 2011 to regulate glass reflectivity, and that Tori Gallas and Partners, as a consultant, recommended regulating visual light transmission. However, OMPR’s glazing expert Jon Weir testified that VLT is not a performance attribute of glass but an aesthetic one, and the HCDA’s mechanical engineering expert testified that “[a] high VLT does not necessarily relate to a low external reflectance.”

Viracon’s VRE1-30, which has a VLT of 28 percent, was selected for its solar heat gain coefficient (SHGC) of 0.19, which OMPR says “was required … to meet the energy model necessary for compliance with the Mauka Area Rules’ Green Building Section, as calculated by OMPR’s mechanical engineers.” The mandate requires an energy reduction of 10 percent compared to a code-minimum baseline.

OMPR notes in the filing that “the more visible light that passes through the glass, the higher the SHGC, which in turn results in more heat gain or buildup on the interior of the building. … There is a direct correlation between VLT, SHGC, and the overall performance of various glazing systems.”

The developer claims the industry standard of VLT is 20-40 percent, and that it has found no glazing product that can achieve the authority’s 50-percent VLT rule while still meeting the 10-percent increased energy performance requirements.

Weir suggests the Authority should look at other jurisdictions’ approaches to “accommodate tenant comfort and limit energy consumption,” such as California’s Title 24. “The difference is that California’s (method) is an approaching limiting U value, Relative SHGC and VT, or visible transmittance, which is defined as the rating for overall daylight transmittance of [the] product including frame. The key here is that there is an understanding that VLT (or VT) cannot be regulated alone but only as a part of three interrelated factors affecting performance of exterior wall systems.”

In conclusion, OMPR asserts that the Hawaii glass rule conflicts with the green building rule and that the sustainability and energy efficiency considerations are “paramount” to the glass rule.

Meanwhile, Honolulu City councilman Trevor Ozawa recently introduced a resolution urging the HCDA to uphold the glass rule, and that waiving the conditions for the Symphony Honolulu project would “set a bad precedent.”

The resolution reads, in part: “[A]lthough the Council concurs with the need for making energy efficiency a priority in the development and construction of buildings, it is also concerned with the impacts of daytime glare generation associated with buildings with highly reflective surfaces, since such glare may cause public safety issues for motorists, bicyclists and pedestrians traveling on nearby roadways and sidewalks and discomfort for persons living and working in the project vicinity.

“[A]nd … Section 21-4.80 of the Revised Ordinances of Honolulu, applicable to buildings in Honolulu outside the jurisdiction of HCDA, prohibits any building wall from containing a reflective surface for more than 30 percent of the wall’s surface area.”

Sixty-eight public testimonies were submitted in regard to the ruling, with 65 people voicing support and just three opposing the developer’s request to waive the glass rule.