Swimming Sustainably

A building that houses a swimming pool would seem to be a poor candidate for LEED Platinum status. But the East Portland Community Aquatic Center shows that isn’t the case. Swimming pools are “energy hogs,” says Eric Ridenour, architect at SERA Architects in Portland, which oversaw the project. But between the city’s mandate for LEED Gold certification in construction, and the Park Commission’s commitment to a building with green features, the Aquatic Center is a model for energy saving, water conservation, and daylighting.

It wasn’t easy. Swimming pools have special requirements for temperature, humidity and air quality. Ridenour says, “You have to heat the pool, keep the air comfortable, and people are wearing minimal clothes and are wet. Part of comfort is good air quality. You need fresh air from outside, which uses a lot of energy.” Another challenge was in using daylight.

Between SERA, Interface Engineering, WaterTech, and Brightworks, which advised on LEED certification, the challenges were met. Energy savings, according to Ridenour, came mainly from capturing heat from exhausted air. There’s also a heat recovery unit that heat the incoming water before it reaches the boiler.

But the biggest saving came in the form of water. Nicole Isle, project manager for Brightworks, which consulted on LEED certification for the project, says, “The savings in potable water were enormous—1.2 million gallons a year.” An innovative approach to filtering the pool water was in large part responsible. Conventional systems use “backward washing” to clean the filter. The water goes to a sanitary sewer—literally down the drain.

The Aquatic Center’s filtration system uses perlite. Ridenour says, “Because of the shape and physics of perlite, it doesn’t need to be backward washed. We saved capital cost and reduced water use.”

Daylighting was tricky, given the existing lights and the need to reduce glare. The design team relied on a modeling process. They built a physical model and took it to the University of Oregon’s Energy Studies in Buildings Lab, which had two tools to model daylight. One was the “heliodon,” which shines light to mimic sunlight at various times of the day. The other was an “artificial sky,” a big box with mirrored walls and a ceiling full of floodlights. To use it, the teams attached daylight sensors to the model, turned on the lights, and hooked it up to a computer. The sensor gave them the daylight factor for the project.

Testing the Model for Daylighting

The Design Team Tests the Model for Daylighting

The building’s window design and glazing were crucial in bringing in daylight. The building has clerestory windows that have been carefully positioned to admit daylight. Different glazing types also help. Ridenour says, “At the ground level, it’s transparent, and higher up it’s translucent.”

The building also relies on solar technology—a PV array on the roof, and a smaller thermal array that heat the water for showers. The financing was as innovative as the technology. Isle says, “Budget wise, we were fortunate. In Oregon there are incentives for solar and there’s a business energy tax credit available for non-taxable entities like the city.” The solar panels were the result of a third-party arrangement between the city and Commercial Solar Ventures (CSV) of Portland, in which they captured the incentives and the owners of the building got the electricity. The city will eventually own the system. Isle says, “After CSV collects the incentives, they’ll sell it to the Parks. You need creative financial knowhow to make the system work.”

Image courtesy of SERA Architects, Portland, Oregon.


Leasing Green

Retail tenants and their landlords have been slow to think about going green. Retail leasing has been about square footage and location, not sustainable design or building operation. But that’s about to change, thanks to the new Green Retail Guide, developed jointly by the USGBC and Portland, Oregon-based Green Building Services (GBS).

I talked recently to Nina Tallering, Manager of Verification Program Development at GBS, who has overseen the development of the Guide.

Why have retailers gotten interested in sustainability?
Tallering: For some retailers, it goes with their mission of being good stewards. Then they see the benefit of energy or water savings—there have been amazing results. Other retailers feel they’ll be more competitive by doing it. Even though retail has been slower to pick up than commercial, office, or public buildings, once retailers decide to do something, they do it quickly.

How will the Guide help retailers?
Tallering: We recognized for the Guide to be useful, it couldn’t just be about leasing, but about the whole leasing process—the site/lease/building/operations process. There are LEED elements throughout the whole process. It’s a useful tool and provides awareness about the LEED requirements and integrating the sustainable goals of the retailer.

There’s a wide range of retail lease types and situations. Malls, lifestyle, power centers, with triple net, gross, land leases. There are a wide number of variables. This is applicable to all of them.

We hoped to target any retail tenant from the big boxes to the small mom-and-pops. There’s a difference in restaurants and apparel—they have different energy uses. We tried to make it applicable to any tenant.

How is green leasing different from conventional leasing?
Tallering: This is an opportunity for landlords and tenants to develop a different kind of relationship and work toward sustainable goals. It starts to foster better communication. It’s like integrated design—it’s easier to meet your goals. It’s the same in the landlord/tenant relationship. When goals are discussed, before the lease is signed, those conversations are going to foster a willingness to get LEED information into the lease and even to integrate more sustainability into operating practices.

It’s new territory for both sides. With landlords and real estate developers, in looking at tenant requirements that have to do with LEED, tenants aren’t sure how much is okay to ask for and what can make or break a deal. In retail, it’s been about location, location, location. We’re hoping that with more education, both retailer and landlord will recognize that even though location is crucial, other things can be appealing.

Are there other benefits of green leasing?
Tallering: When people see that green isn’t weird or crunchy, that the stores look the same, it goes a long way. When retailers talk to consumers, they educate them. And there’s brand loyalty born of sustainability. Green products or green buildings provide so much potential. When retailers spend time on stores, it makes financial sense.

Don’t Preserve the Ants

It’s hard to believe that many of the modern buildings of the last century are now more than fifty years old. One thing that made them “modern”—new and experimental materials—has become a problem as these buildings age. Traditional materials—brick, wood, tile—are remarkably durable. Plywood and plastic, it turns out, are not.

In many modernist buildings, experimental materials are integral to the building’s appearance and aesthetic. Barbara Campagna, and architect with the National Trust, speaking at a 2008 panel on “Preserving Modernism in a Green World” at the National Building Museum, pointed out that a curtain wall of plate glass is essential to the design of the Glass House. If the glass breaks—endangering anyone nearby—is it still the Glass House if the curtain wall is replaced with new tempered glass?

When Bob Close and his wife Cindy Peltier decided to renovate the house that had been Bob Close’s childhood home, they squarely faced the dilemma of preserving modernism. His mother, architect Elizabeth Close, is renowned in Minnesota for houses in the modernist style. The house she built for her family in 1954 was informed by her commitment to modernist design and relied on modern materials.

Close House Front Exterior

Close House Front Exterior

Bob and Cindy hired friend and architect Peter Kramer, who knows Liesl Close (as her friends call her) personally and professionally and admires her work. They began a lengthy process of renovation and restoration. He said, “When we first started talking, Bob and Cindy made it clear that it was important to be sensitive to the integrity of the house. Every step was a cautious effort not to rip it apart.”

The house’s plywood paneling became a touchstone for their discussion about preservation. Ironically, Liesl Close chose plywood because it was modular, easy to maintain, and at the time, cheap. It was in rough shape. Behind the plywood was an unpleasant surprise—nests of ants and mice. The walls were full of decade-old dead ants. Replacing the plywood was prohibitively expensive. Bob Close said, “If we were made of money, we would have replaced the plywood at $70 a sheet.”

Close House Fireplace Showing Plywood

Close House Living Room before Renovation

But the decision to go in another direction was prolonged and difficult. Peltier said, “It was every little step. We had to go through each piece of plywood. Can we keep this piece of plywood? At each step we were very slow. That’s why it took a year.” Kramer agreed. He said, “It was a struggle. There was the respect for the original design on one side, and the issue of Bob growing up as a little kid in this house—he had an enormous familiarity.”

Bob Close and Cindy Peltier made changes. They replaced the plywood. They opened up the pass-through between the dining room and kitchen. They also opened the back hallway and put it a skylight. They kept the built-in furniture and bookshelves intact, and they were happy to retain the cedar shingles that gave the exterior its character. By the end of the project, it had become their house, and looking back on the lengthy process, Peltier said, “We were never sorry.”

Close House Living Room After Renovation

Close House Living Room after Renovation

Kramer felt strongly that the renovated house was still modernist in spirit. He said, “People are going to restore any house that has some architectural character, particularly this period. Modernism isn’t a style, it’s an attitude. It had to do with how people lived and how they saw the world. People who are working on modernist houses aren’t trying to replicate the ‘modern style.’ You can take a house done by someone like Liesl and incorporate the way that new people live in the house.”

It’s still the Close house. But it’s now home for a new generation of Closes.

A Climate for Green Building

Stahl Construction has been doing business in Minnesota for three decades, and the company is comfortable with Minnesota’s climate—for weather and for building. When they built a Residence Inn for Marriott in Minneapolis, their client was impressed and asked them to bid on a similar project in Portland, Oregon.

Stahl’s Portland project was part of the Cascade Station development, land located near the Portland airport. Built in 1999, Cascade Station began as a light rail stop on the way to the airport, but the city of Portland had a bigger vision for the site—an “urban village” that involved retail, hotels and restaurants. After 2001, the project languished, but in 2005, the city changed the zoning requirements to allow big retail tenants. IKEA agreed to build a store on the property, and Best Buy and other retailers followed suit. Three hotel owners—Marriott, Hyatt, and Starwood—also committed to building on the site.

Cascade Station in Portland, Oregon Retail corner

Retail stores at Cascade Station, Portland, Oregon

Greenery at Cascade Station

Greenery at Cascade Station, Portland, Oregon

Stahl was the general contractor for the Marriott Residence Inn and Hyatt Place projects. They found that Portland’s climate is a lot different from Minneapolis’s—not just the temperate weather, but the building climate, which has been influenced by Portland’s long-time commitment to sustainability in design and construction. Alisa Kane, Green Building Manager for Portland’s Bureau of Planning and Sustainability, says, “The building code is at the state level as well as the city. We were one of the first states to have an energy code. We know we have a complex regulatory structure, but we want to give builders assistance and make it cost-effective to do business here.”

Portland’s codes led to some adjustments in the building process and in the level of sustainability the finished projects achieved. Brenda Studt, Director of Marketing for Stahl, said, “They weren’t going for LEED certification, but were building to Portland’s standards.” In keeping with local concerns about sustainability, the project recycled 94% of the construction waste and sourced 20% of the building materials within 500 miles of the project—reducing fuel required for transport.

Marriott Residence Inn at Cascade Station, Portland OR under construction

Residence Inn at Cascade Station under construction

The proximity to public transportation was a sustainable plus for Stahl and its clients. Building materials included recycled content, and low VOC paint was the rule. Both hotels relied on controls for exterior lighting, and common spaces were provided with large, energy-efficient windows to maximize daylight and decrease energy use.

Hyatt Place under construction, Portland Oregon

Hyatt Place at Cascade Station under construction

Stahl was able to satisfy the city’s requirements and please both hotel clients. They weren’t fazed by building in Portland. They’re confident enough about more projects to have a Portland office.

Images of Residence Inn and Hyatt Place courtesy of Stahl Construction
Images of Cascade Station courtesy of the Portland Development Commission

A Well-Watered Green Roof

We’ve become accustomed to rooftop gardens—several stories up. When you walk through the “rooftop” garden at the Bookmen Stacks loft building in Minneapolis, you’re on ground level. It’s a garden planted on the roof of an underground parking ramp.

Bookmen Stacks Garden and Building

Bookmen Stacks Garden and Building

The area has very little greenery—the building itself faces a highway overpass. The project’s developer, Steve Frenz, wanted some green space and was open to new ideas. He’d worked with the landscape architects, Oslund and Associates, before, and asked them to come up with a plan.

Creating a rooftop garden had a few challenges. One was structural—working with the weight of the roof, and compensating for the fact that the roof slopes. Bookmen’s immediate neighborhood has no storm sewer, so managing stormwater was another challenge.

Tom Oslund, principal of Oslund and Associates, needed a way to combine storage and irrigation. He found it in a system manufactured by a Minneapolis company, RESI Inc. The system has three parts: a liner to store water, a chamber to control the water flow, and a sand fill.

In the Bookmen Stacks garden, the system stores stormwater in cisterns buried on the roof, and draws it through the sand as needed by relying on capillary action. Oslund says, “It is able to irrigate more efficiently, and you don’t see any of it. The surface becomes very durable and we’re not casting or using water. It’s all done through wick irrigation.”

The sand fill is good for plants, especially turf. Oslund says, “The biggest challenge presented by turf areas is compaction. It kills the root structure. With sand as a matrix, it doesn’t compact. It stays firm and the roots survive.”

Bookmen Stacks Garden, Aerial View

Bookmen Stacks Garden, Aerial View

The system has other advantages. One is that gardens that rely on it need less soil than other rooftop gardens—6 to 8 inches as opposed to 12 to 14. The design of the parking ramp didn’t need to factor in the additional weight, which saved on construction cost. The system has no moving parts—the only element that moves is water. Oslund says, “It’s so simple that there’s not much that can go wrong.”

Planting the garden was really not different from putting plants in a pot. And it let Oslund plant taller plants—ornamental grasses and larger plants in pots. Oslund says, “It has the appearance of something that’s not on the roof. You’re hard pressed to realize it isn’t growing out of the ground.”

Bookmen Stacks Garden, Front View

Bookmen Stacks Garden, Front View

The result was, Oslund says, “an open space in an area surrounded by access ramps to the freeway. It’s a respite spot.” The building’s dogs like it too—it’s a good place for them to run and play. The garden looks and feels like a private park for the people who live in Bookmen Stacks.

All images courtesy of Oslund and Associates.

This Book Comes with a Fountain

I’m stingy when it comes to buying books. I don’t like to own a book unless I know I’ll reread it with pleasure or refer to it again and again. So when I wanted to read Robert Winter’s biography of tilemaker Ernest Batchelder, I didn’t order it online. I ordered it from the public library.

When the book arrived, I opened it to find this snapshot tucked inside the front cover, which the photographer had helpfully identified. This is a picture of the drinking fountain surround at the Keewaydin Elementary School in south Minneapolis, built in 1924 and still in use today. You can see the garbage pails and the hand-lettered poster on the wall.

I would credit the photographer if I knew who it was!

Keewaydin School Fountain Surround

Ernest Batchelder is best remembered today for his California tile company. Between 1912 and the late 1930s, his workshop—first in Pasadena, then in LA—made field and decorative tile that was installed in California and elsewhere. But he had strong ties to Minneapolis.

Between 1904 and 1909 he directed the summer school at the Minneapolis Handicraft Guild, which served as a school and a professional association for people interested in decorative metalwork, pottery and tilemaking, leatherwork and jewelry making, and bookbinding.

One of his first installations ever still graces the lobby floor of the old Guild building in downtown Minneapolis. Batchelder used the designs he created for the Guild’s tiles for the rest of his career.

Batchelder Floor Tile in Handicraft Guild Building

Batchelder Floor Tile in Handicraft Guild Building

When the Batchelder Tile Company expanded during the post-World War I building boom, it made perfect sense for Batchelder to open a showroom in Minneapolis. His old friends were artists, architects, and well-to-do homeowners.

Minneapolis buildings from the 1920s, both public and private, are filled with Batchelder tile. I’ve had the pleasure of straying into more than one south Minneapolis house, built in the 1920s, to be able to identify a fireplace design straight from Batchelder’s mantel catalog.

Educational institutions used Batchelder tiles. The University of Minnesota’s original music building has lovely installations, and the College of St. Catherine in St. Paul has stunning examples. The Keewaydin school’s installation is smaller and less ornate. But it is as pretty an example of multicolored Batchelder field tile as you will see anywhere.

Like a lot of school districts, Minneapolis has been suffering financially, and the city has consolidated enrollments and closed school buildings. The Keewaydin school is still open and the tile is still intact. I’ll keep an eye on it. I like to think of the kids seeing that tile every day as they take a drink of water.

Sustainability in the Lavatory

Unless your commercial building has a cooling tower, most of the water used there is in the loo. According to Jim Keller, partner for Sustainable Design at Gausman & Moore, an engineering firm in St. Paul, Minnesota, about 60% of water used in an office building goes through “restroom plumbing.” Here’s how to save water while people are, ahem, producing it.

As an added benefit, all of these technologies—with the exception of the waterless urinal—are good to have at home, too.

Low-flow faucet aerators: The easiest way to conserve water is to limit the amount that comes out of the faucet. People should wash their hands in the loo, but aerators let them do it with up to 50% less water than conventional faucets. Conventional faucet aerators deliver 2.5 to 5 gallons of water per minute. Low-flow aerators deliver 0.5 to 1.0 gallons. Low-flow aerators are easy to install and have a swift payback period.

High-efficiency and ultra-low flush toilets: Both of these use about half of the water of conventional models, averaging 1.6 gallons per flush instead of 3.5. Ultra-low flush models are the more efficient of the two, using only 6 of the tank’s 13 liters per flush. An ultra-low flush model can be fitted with a dual-flush valve (see below) for even greater efficiency.

Dual-flush valves: Dual flush valves save water by offering two different water closet options: one for liquids and the other for solids. The real saving comes in the liquid option: it uses 0.8 gallons per flush, as opposed to 3.5 in a conventional commode or 1.6 in a high-efficiency version. Dual-flush valves can be easily retrofitted onto existing toilets.

Waterless urinals: Even though waterless urinals were introduced as early as 1992, they’ve since been refined, and interest in them has grown as building engineers and managers become more conscious about conserving water.

Waterless urinals use a sealing liquid—typically an oil, which is less dense than urine—that lets urine flow through and sink beneath. The oil traps any odor. There are two types of waterless urinals, one that uses a cartridge, which encases the sealing liquid, and non-cartridge systems, which put the sealing liquid directly into the drain hole. Waterless urinals don’t need piping, flush controls, or sensors. They greatly reduce maintenance and installation costs.

Despite the benefits, many people—plumbers, building engineers, and lavatory users—are resistant to the idea of waterless urinals. Plumbing codes in many cities prohibit their use. Success in installing a waterless urinal is likely to require 1) big increases in water costs; 2) significant commitment to water conservation; 3) education on the part of anyone who uses the lavatory.