Loyola University's new facility has green mechanical
systems just as innovative as its library services.
If you think college students type term papers these
days, you’re probably still listening to a Duran Duran cassette on your
Walkman. Grab an iPod and step into Loyola University’s newest addition to its
Chicago Lakeshore campus and you’ll see what we mean.
The university opened the $32 million Richard J. Klarchek Information Commons a
year ago last month. The four-story, 70,000-plus square foot glass structure
rests just 20 feet from Lake Michigan and essentially serves as a library –
just not the kind you might be used to.
You won’t find books in this library but rather quick access to digital
information. That’s a key service for today’s students who have to create
electronic, media-rich content for their class work that might include a
PowerPoint presentation as well as an embedded Flash program. These days, students
also collaborate on assignments differently, sharing ideas electronically as
easily as you may have traded your scribbled class notes back in the dark ages
of, say, the 1980s.
So no books, but the Information Commons does feature more than 200 networked
computer workstations, 50 laptops for loan and building-wide WiFi access all
tied into the university’s extensive electronic library resources. (And in case
you’re wondering as I was, yes, there is an old-fashioned library, the kind
with books, connected right next door.)
The new facility is the first phase of the university’s plans to upgrade its
academic research facilities. While the Information Commons represents the
forefront of academic research, it’s the building itself that’s at the
forefront of green mechanical building for our purposes.
Plans for the building were designed to cut energy use by half — and early
indications are that the systems are performing a little better than that. As a
result of energy reductions, cuts in water use and everything else that goes
into constructing such a green structure, the university is hoping to
eventually earn Silver LEED certification for the facility once all the
approval processes are completed.
While students are downloading a document from halfway around the world, we
doubt many will appreciate the mechanical work that will keep them comfortable
year-round in this high-performance building that’s open
24/7.
How many students are likely to look up at the ceiling and realize hidden away
are 15 miles of 5/8-inch PEX tubing that provides the wide-open study areas on
two floors with radiant heating and cooling?
For this type of academic research, we paid a visit to Hill Mechanical Group, a
Chicago-based PM Pipe Trades Giant started in 1936 that ranked No. 6 in our
2008 list of the country’s largest plumbing and piping mechanical contractors.
You can’t walk one step into the company’s suburban headquarters and not notice
the sign that touts how the company is building a greener Chicago. And we
barely got the introductions in order before
James B. Hill
III, vice president, handed us a thick sheath of color copies of past
projects that reads like a Who’s Who of green building in
Chicago.
“Our customers are very conscious about energy these days,” Hill explains.
“Because of this, almost every one of our jobs starts out as LEED-certified or
has a commitment to reduced energy consumption.” He doesn’t think the
relatively recent growth of green building is new to how the company has grown
over the years. He says his father,
Warren Hill, currently
the company’s chairman, would routinely try to save building owners money on
energy and not just bring in a lower bid based on first
cost.
“I don’t think anything has changed internally for us,” Hill says. “It's just
that with so much emphasis in Chicagoland on ‘LEED’ and ‘building green,’ we
now have recognized names to call the type of work the company has always tried
to provide for its customers.”
Hill’s work for Loyola’s new building presented a number of challenges. As far
as anyone can tell, the building features the country’s first use of a precast
radiant ceiling system manufactured by a Wisconsin company called Advance Cast
Inc.
“The building materials themselves are typical,” says
Greg
Ivaska, senior mechanical designer, “but putting it together — no one
had experience with it before.”
Basically, the Hill crew had to prepare ceiling sections measuring 30 feet by 8
feet with about 300 feet of PEX laced around the rebar for each. In all, there
were approximately 80 panels per floor.
In many ways, it helps to think of the building as being constructed upside
down: The tubing may be buried in slab, after all, which doesn’t make it out of
the ordinary. But since it forms the ceiling and not the floor, the Hill crew
had to carefully account for other openings for the electrical and fire projection
systems.
A grid of PEX tubing was tied to the rebar skeleton of each section before each
piece was cast at the Wisconsin factory. Ultimately, what you see looking up at
the ceiling of the finished building is nothing more than the painted surface
of the concrete.
Meanwhile, ductwork for an air distribution system, which primarily serves the
building’s standard ventilation requirements, runs under the raised
floors.
A week after the office visit, we took a tour of the Information Commons, along
with
Wayne Silwa, project manager for the university, and
David Lavan, engineer with Elara, Hillside, Ill., the consulting
engineer for the building.
How It All Works
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| Here’s what the radiant ceiling looked like before the sections were cast. |
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The building really is a site to see. Picture a
four-story glass box though which you can view Lake Michigan in the east
straight through the building as you walk up to the west entrance. On the north
and south sides of building are “bookends” constructed with material designed
to mimic the style and limestone looks of the older Art Deco chapel and library
on each flank.
Although the university wanted the building to be as transparent as possible,
it also wanted it to be as energy-efficient as possible. With all that glass,
that’s quite a challenge.
Before we go forward with our explanation of Hill’s mechanical work to heat and
cool the space, we should point out that much of what follows only applies to
the open study spaces on the first and second floors. Those bookends we
mentioned house classrooms and offices, which are largely heated by traditional
HVAC. A fourth floor, actually a partial floor with a vegetative roof taking up
about half the space, doesn’t get the radiant treatment either. Finally,
stairways are warmed with hydronic baseboard.
However, the open study areas are indeed quite open — 150 feet by 90 feet — and
certainly highlight the primary advantage water will always have in
transporting heat and coolness to such space.
In heating season, basically anytime the outdoor temperature drops below 55
degrees F, the radiant tubing embedded in the ceiling provides much of the heat
needed for the study areas, although there are a couple of methods to maintain
the indoor temperature:
- About 1,200 feet of hot water
finned tube lies just below the floor line along the east side of the study
areas.
- A system of air handlers also supplements
the radiant ceiling and delivers warm air through ductwork and vents installed
under the floors.
But it’s in the warmer months of the year that the
building really earns its LEED stripes. It operates mechanically as you would
expect, but also naturally through a high-tech variation of the old notion of “opening
a window.” Finally, it can operate as a hybrid combination of the two.
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| The structural precast radiant ceiling provides heating and cooling for
the wide-open study areas inside Loyola University’s digital library. |
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NaturallyObviously,
if a building’s mechanical systems can be shut off, energy bills drop. Despite
all the glass, the Information Commons is far from being the typically hermetically
sealed building.
When the weather permits and temperatures range from 55 and 68 degrees F, the
building’s automated system shuts off the air handlers and opens windows on the
west and east sides, allowing fresh air to naturally ventilate and cool the
study areas.
Motorized windows on the east side open directly to the outside, but it’s the
west side that produces much of the natural ventilation to move the prevailing
lake winds from east to west.
The west side features a double glass curtain wall, the first of its kind in
Chicago, with windows that open into the interstitial space. Dampers below the
ground level draw in outside air through the bottom of the space while
motorized awning windows up top the three-story curtain naturally exhaust the
warm air out like a chimney.
Of course, there’s a whole lot more to this than just opening some windows.
With all this glass, blocking the sun’s rays is of great importance during
cooling operations. The building’s automated system includes a weather station
that even takes celestial readings of the sun. With that data, an outdoor light
sensor triggers the precise angle of 4-inch blinds to deflect the afternoon
sun. (The blinds, situated inside the cavity, can also be moved up and down,
too.)
On the east side, simpler, but no less effective, roller shades diffuse the
morning sun. Special coatings on the glass on both sides further keep solar
gain in check throughout the day.
Keep in mind that this building is open around the clock, so much of the
natural ventilation mode will take place at night. What’s more, the slab will
naturally retain the nighttime’s “coolness” and help keep the space that much
more comfortable even into the early hours of the morning without relying on
the mechanical mode.
HybridThis
combination of the mechanical and natural means the windows are open and the
radiant ceiling is on.
This mode is only allowed when the outdoor dew point is 5 degrees F below the
chilled ceiling temperature. Controlling the dew point is critical with this
much radiant ceiling mass. The building’s design controls are based on the
following:
- The dehumidification properties of the outside
air that ventilates the open study areas is improved through a three-coil
runaround system.
- A separate return air path on the open areas’ air handlers with
staged coils dehumidifies the space.
- Classrooms
with conventional forced-air systems located nearby the study area further help
out.
The building’s sophisticated control strategy
automatically makes the needed adjustments. For example, no matter the
temperature, all the windows are closed when it rains and the heating or
cooling needs are met mechanically. Also, if wind speeds are too strong off the
lake, the windows remain closed regardless of the outdoor air temperatures. In
the case of a smoke evacuation signal, some windows, such as the awning
windows, open, while others stay closed and the exhaust fans rev up to high speeds.
We gathered information for this story toward the tail end of last year, so the
building still hasn’t weathered a full Chicago winter yet. However, the
engineering company for the building supplied us with a couple of interesting
realties from the height of a Chicago summer:
- In a two-week
period last August, the building was either in natural ventilation mode or
hybrid mode 37 percent of the time. The natural ventilation mode is so
effective that the indoor temperature could be maintained within approximately
one-half degree of the outdoor temperature.
- Based
on two energy models done by Elara Engineering, the building is actually a bit
more efficient than expected. Last August, the building energy bill for the
month came to $7,333. That figure includes regulated loads for lighting and
HVAC as well as power for the facility’s computers. And it’s actually 4 percent
lower than what the engineering firm’s model calculations figured it might
be.
It’s hard to figure where the building ends and the
outside begins and, in fact, the mechanical engineer told us that one of the
goals of the project was to make it feel like you were outside on a gorgeous
day while still inside working away at a desk.
Other Energy Efficient Technologies
The radiant heating and cooling systems, of course,
aren’t all there is to making Loyola’s new Information Commons a candidate for
LEED Silver status.
Here are some highlights of other materials and systems used in its green
construction:
A green roof absorbs rainwater and limits some runoff into Lake
Michigan.
The building’s restrooms feature dual-flush toilets, electronic
faucets and urinals that flush with 1/8 of a gallon. In addition to an
efficient irrigation system, the building is documented for its LEED
certification to cut water use by more than a third.
Sensors balance artificial light with natural light throughout the
day.
The carpet tiles are made from recycled content and formaldehyde-free
products. Paint and sealant used in construction was all low-VOC
content.
Special surface coatings on the glass, shades and blinds all help
mitigate heat gain.