Interface Engineering

MEP Engineering Firm Transitions to Sustainability

At Clackamas High School, Interface engineers incorporated daylighting, photocells to sense light, and occupancy sensors to turn off lights in unoccupied rooms
– Credit Stephen Cridland

When Interface Engineering began life 35 years ago in Milwaukee, Oregon, its founders probably had no idea what it would become. They originally started with two separate firms, mechanical and electrical, and they merged shortly afterwards to become a traditional mechanical – electrical – plumbing (MEP) engineering firm designing systems for buildings. Simple enough.

Fast forwarding, though, the founders have retired in recent years, and the company has seen a big transition. As Andy Frichtl, a principal and senior mechanical engineer, tells it, “We bought out the original founders of the company, and now about ten principals have taken the reigns and taken the firm in some new directions. Sustainability is one of the new directions we’re heading in.” Indeed, a sustainability movement, with a focus on green building, started five or six years ago and has given the firm its present-day signature.

Combining this new trend with the original foundation has proven successful, as Interface Engineering ranks among the top 40 MEP engineering firms in the U.S. in terms of annual sales. The employee-owned firm employs about 110 electrical and mechanical engineers, designers, drafters, and support personnel. The new partners moved headquarters to Portland, Oregon to be closer to their clients, and Interface has added offices in Seattle, Washington; Salem, Oregon; and Sacramento, California.

Interface has groups that cover commercial, educational, residential, retail, industrial, hospitality, cultural, and institutional facilities. Most of their work comes on the west coast, but they also do work in other areas of the U.S. and overseas. “Just in the last six months, there have been more opportunities for us to grow overseas in different areas, and I think that will continue,” Frichtl reports.

Services offered by Interface vary from conventional mechanical and electrical engineering to a wide variety of specialties. Frichtl explains the sustainability approach by saying, “We’re a fairly progressive firm. We’re looking for the latest, most innovative ways of doing things, but not necessarily ones that cost more. We’re looking at finding ways of doing more with less, spending less money but also saving energy and water.”

Traditional electrical engineering services include things like power distribution systems, power quality testing and monitoring, PLC-based electrical control systems, motor controls, and process instrumentation systems. In recent years, this has expanded to include photovoltaic systems for generating solar energy and on-site power generation.

One specialty that has become most visible for Interface is designing energy-efficient lighting systems. They showcased this at Clackamas High School in Clackamas, Oregon, where the firm provided electrical, lighting, security and access, and telecommunications infrastructure design for its new two-story, 268,000-square-foot building, which opened in 2002.

Daylighting emerged as a central element in the architectural design and energy conservation program at the school. Photocells sense light and tell lighting controls to dim the electric lighting whenever daylight provides sufficient light. Controls also include occupancy sensors to turn off lights in unoccupied classrooms. Software turns off most lights when school is not in session or the building sits unoccupied. With such measures, they reduced overall lighting energy demand by 57 percent compared with Oregon building code. This also allows natural ventilation to work better by reducing building heat gain from lights. Initial results indicate the building uses 44 percent less energy than a similar building designed to code.

Engineer David Chesley (left) discusses a project with Andy Frichtl, principal and senior mechanical engineer.  Courtesy Interface Engineering

As much as possible, Interface engineers incorporate energy efficiency and other sustainable design factors into the mechanical and electrical design of each building they design, keeping an eye on life cycle as well as first costs. “On things that just make sense, we automatically do those,” Frichtl says. “It depends on the client. Some of them have large goals, some of them don’t have any goals at all, and we just bring stuff to the table and say ‘it makes sense to do this even though you haven¹t told us you’re interested.'”

Interface’s approach falls under the mantra of integrated design, which considers a building’s design, structure, and systems as a whole and optimizes their interaction. This involves cross-disciplinary collaboration, especially between architects and engineers, and as a result, distinctions between these disciplines have blurred. And whereas in the past, engineers typically specified oversized systems to cover worst-case scenarios, sustainable designers today lean toward smaller, more optimally-sized systems, realizing that a building may not have to maintain design conditions every hour of every day.

On the mechanical end, Interface’s services include energy life-cycle cost analysis and computer energy use modeling, and they design systems for heating, ventilating, and air conditioning (HVAC); plumbing; water and wastewater distribution and collection; cogeneration; heat recovery; and compressed air. An exciting project is taking shape at South Waterfront, a former shipyard along the Willamette River just south of downtown Portland. Oregon Health Sciences University is expanding their campus with Building One, a new, 360,000-square-foot, 16-story building to serve as a mixed-use facility for wellness, medical research, clinics, surgery, classrooms, and retail. Interface’s team, led by Frichtl, has provided HVAC, plumbing, electrical, power distribution, lighting, and fire alarm systems design.

Building One uses variable-air-volume air handlers and variable-frequency drives on pumps and motors to match supply with demand. Ventilation systems use carbon dioxide sensors and occupancy sensors, so spaces are fully conditioned only when used. Heat recovery systems capture waste heat from laboratories, general exhausts, and locker rooms. Upping the sustainable ante, the building also boasts an array of solar panels, natural ventilation, radiant cooling, rainwater harvesting, and a microturbine-based energy-generation plant, which will harness 80 percent of the thermal energy it generates as a byproduct.

Now under construction, Building One at Oregon Health Sciences University will feature a host of HVAC, energy conservation, lighting, and water conservation measures and serve as a showcase – Credit GBD Architects

“It’s not a typical project, but it kind of paves the way showing people you can actually do something like that,” Frichtl relates. “You get incredible results, and it costs less than a traditional building. It was really an interesting project.” It stands about 20 percent complete now, and upon its completion in 2006, they expect Building One to achieve energy savings at 61 percent greater than what Oregon code requires while cutting upfront costs 25 percent.

With successes like this, Frichtl sees the demand for sustainable design increasing. “We’re at 30 or 40 percent of our projects being sustainable right now, and I see it growing. I don’t think the price of energy’s going to go down. I think it’s just going to continue to be more and more important for everyone, and water conservation as well, air quality, all those things. That demand has got to increase.” Thanks to the overall path Interface has taken since its beginning, he can say,
“We’re in a growth mode right now, and I think that will continue.”


Interface Engineering

Type:Consulting mechanical, electrical, and plumbing (MEP) engineering firm

Location: Headquarters in Portland, Oregon with other offices in Salem, Oregon; Seattle, Washington; and Sacramento, California

Contact information for submitting resumes:
E-mail to Beverly Markstrom at

Outlook for hiring engineers: “We’re always looking for good employees. Our demand is always high,” reports Andy Frichtl, a principal and senior mechanical engineer. “Over time, we want to keep growing. We owe that to the stockholders. We want to give opportunities to other people.”

What they look for in engineers: “It isn¹t just the technical capabilities,” Frichtl says. “If somebody¹s really passionate about something, they’re going to excel in it. We’re looking for that kind of energy from people.” As for experience level, they hire at all levels — entry all the way up to potential partners. They may branch out and open new offices.”

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