Upgrading for Lower Energy Costs
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More often than not, when boards or associations broach the issue of their
buildings “going green,” images of bamboo flooring, hemp drapes, or solar panels on the roof suddenly
spring to mind. The impression seems to be that in a condo, green upgrades are
difficult and costly—if not impossible—to do.
Fortunately, the truth is that there are plenty of things co-op and condo boards
and owners can do to reduce their community’s environmental impact without
vaporizing its bank account.
One Small Step for Green
According to the experts such as David Unger, CEO of New York-based U.S. Energy
Group, green starts small. “When you really start looking at what it takes to go green, you recognize that
it’s all about cutting energy use. If I can use less oil, I’m going green by
virtue of the fact that I’m not dependent on oil.”
Architect Kirsten Thoft agrees. “The cost of heating and cooling and the amount of energy consumed doing those
things, either oil or natural gas or electricity are huge, and easily
reducible. The most important things that you can do to any building aren’t
sexy, and you don’t even see them—which is part of the reason people overlook them.” Those things however, are easily done.
Fundamentally, the key is to improve the energy efficiency and durability of a
community’s property. Tightening up the building envelope need not cost an arm and a leg,
and can actually yield a higher rate of return than solar panels or recycled
countertops.
The first and sometimes easiest step, according to Green Building Advisor (GBA),
an online resource for information on designing, building, and remodeling
energy-efficient, sustainable homes, is to: “Fix what exists. Starting with simple improvements that don’t take much time or
money can pay off immediately.” The website recommends taking a good look at your association’s exteriors and
being proactive about any needed repairs, “especially those related to weather-tightness and structural stability. Roof
leaks, cracked and bulging foundation walls, and rotten framing are the kinds
of problems that should be corrected before anything else happens.”
The Envelope, Please…
Another key to improving your community’s energy efficiency lies in what is known as the “building envelope.” According to GBA, the building envelope, or shell, is the part of a structure
that you can draw a line around. The enclosure begins in the ground with the
foundation and floor, extends upward as the above-ground walls, and is capped
with a roof. Each part of the enclosure faces different challenges.
“Like three blind men and an elephant, each part of the envelope sees the world
differently,” says Nancy Hazard, former director of the Massachusetts-based Northeast
Sustainable Energy Association (NESEA). “The roof suffers searing sun, pounding rain, and hail. The walls endure sideways
wind and rain. The foundation is surrounded by dark, wet ground. However, the
connections between these parts represent the greatest opportunities for energy
savings.”
Improving on the tricky balancing act played by the roof, walls and foundation
is considered one of the most effective tools for cutting your energy bills. “People have heard that your building can be too tight and it’s not good,” says Hazard, “but unless you have a very new, super-insulated home, it probably is not tight
at all.”
According to green remodeling expert Carl Seville, if you’re looking to pay less
in utility costs, “It is imperative that you first reduce your home’s electric load to a minimum.” One way to do this is by taking on the ‘air barriers’ of your building—the places where different structural planes meet thus creating the opportunity
for leaks and drafts. According to GBA, the trouble spots for air leaks are
where the foundation meets the floor framing, the floor meets the walls and the
walls meet the roof. And any leak, in turn, affects the energy that goes into
cooling and heating your home.
Addressing these spots by tightening them up with caulk, expanding foam sealant
and weather-stripping, or by adding more insulation, are relatively inexpensive
methods but they will do wonders in making the building more energy efficient.
Raising the Cool Roof
Seville also notes that one need not go overboard when greening a roof. “The most sustainable roof is one that uses the fewest natural resources to
produce, and is manufactured locally (reducing the need for transportation and
its associated pollution), and is energy efficient and long lasting.”
According to Amy Westervelt, an author for the U.S. Green Building Council
(USGBC), which has a large chapter in New York City says, most people can have
a “green” roof fairly easily, and without an exorbitant cost. Small improvements can
deliver a big difference, not only to your home’s energy usage but also to the size of your energy bill, she says. Two simple
steps, Westervelt says, are to “cool your roof” and “insulate from below.”
“Cool roofs refer to roofs that are cool in both senses of the word,” says Westervelt. “Lighter in color than traditional black asphalt or dark wood shingles, cool
roofs save energy by reflecting light and heat away, rather than absorbing
both. This is known as the albedo effect, and study after study in the last few
years has documented significant energy savings from simply lightening the
color of a roof.”
Westervelt acknowledges that the problem with a dark roof, especially in New
York City, is that the temperature may be 95 degrees outside but a dark roof
conducts heat at a much higher temperature down to the inhabitants of a
building. This naturally makes the rooms below hotter—and as a result the cooling systems have to work much harder.
A perfect example of cool roof technology is The Seville, an upscale co-op in
Bayside, Queens that had suffered from leaking roofs for years. The Seville,
managed by Metro Management, features 18 townhouses and a 17-story apartment
building. The residents of The Seville and property manager Yves M. Martinez of
Metro Management were searching for a solution and as recently as last summer,
the cooperative’s board of directors was considering total roof replacements for the nine
buildings, which house the cooperative’s 18 townhouses, according to a product news release. It was suggested by Long
Island City-based National Roofing Corporation to use a product from EPOX-Z
called NRG™, which is a white solventless, odorless coating that was engineered to mitigate
the damaging effects of ponding water and eliminate leaks on flat roof
surfaces.
“We had serious leaks in our townhomes, and any time it rained I would cringe
because I knew I was going to get complaints,” said Martinez, who noted the estimate for roof replacement for The Seville’s nine townhouse roofs was more than $350,000. “Now I don’t have to worry about that anymore, because since we put down NRG we haven’t had any leaks or complaints,” said Martinez, who added that the building was also considering converting to a
green roof had the cool roof coating not been successful.
Dennis Cohen, vice president of National Roofing Corporation in Long Island City
installed The Seville’s new roof, and says that newer more energy-efficient roofing methods are only
getting better and more effective as more and more consumers come on board.
“The coating is actually the last process,” Cohen says. “First, we prep the roof. We fix any flashings, we fix the drains, and any
defects. Then we power wash it to get all the grime and the dirt off. We go
through all the seams with the first layer of epoxy mastic, and then we apply
the coating. Sometimes we spray it. Sometimes we put it on with a squeegee or a
roller. We almost make it like an assembly line. It’s dry within two hours, depending on the weather.”
And Cohen says he’s impressed with how durable the coating is once it’s cured. “I was blown away by how it hardens up. It almost looks like a paint, but it
hardens up to like a rubber,” he says. It’s also suitable for any type of roof from built-up or BUR to metal and EPDM,
which is an ethylene and propylene polymer surface. “I’ve been around a long time, and seen so many things come and go, but this is
really beautiful when it’s done. It’s easy to apply, but the prep work is the whole core of it. It’s really fascinating.”
In addition to substantially extending the life of the roof, studies have shown
that cool roof coatings can lower interior temperatures of a commercial or
industrial building by as much as 12 degrees Fahrenheit during the hottest four
hours of a summer day and reduce peak cooling demand by as much as 15 percent.
According to Cohen, installing a cool roof coating is actually $4 to $5 less a
square foot than replacing a traditional asphalt or EPDM surface and the
installation process, prep work included, is probably about two weeks.
Green building consultant Barbara Collins of the California-based firm EHR West,
points out that, “a dark-colored asphalt roof can reach 150 to 175-plus degrees on a hot summer
day. This not only increases the energy needs of the home, it also contributes
to the heat island effect in urban areas.”
In contrast, Westervelt says, a cool roof can be 50 to 60 degrees cooler than a
conventional dark-colored roof, reducing the cooling load on the building,
saving energy and reducing utility costs. “By decreasing the solar gain and heat retention of your home, a white roof also
increases its comfort and reduces the heat island effect. The easiest route is
to slap a cool roof coating onto an existing roof.”
Westervelt says that a quick search of the Cool Roof Rating Council’s Rated Products Directory provides you with performance data about various
roofing products. Products are rated for their reflectiveness on a 0 to 1.0
scale; the higher the number, the more reflective the product is, and the
cooler your roof will be. “Simply choosing the right material could result in as much as a 30 percent
decrease in your home’s energy needs,” says Westervelt. Whether that ends up being a tile roof, asphalt shingles,
metal, concrete, or even wood, experts recommend reflective coatings to make
your roof cool, she says.
Insulate, Insulate, Insulate!
Insulation, Westervelt says, is one of the first things people should think of
when they plan on making their homes more energy efficient. “According to the Rocky Mountain Institute (RMI), the attic is usually the top
priority because installing insulation there is easy and provides immediate
benefits. And when insulating the attic, it’s important not to forget about the roof.”
An inadequately-insulated roof is a heating and cooling system’s biggest
nemesis. It requires twice as much air conditioning in the summer months and
higher heat in the winter. “And if you have any dreams of actually inhabiting the attic of a house with a
poorly insulated roof, forget about it,” says Westervelt. “Even if you do have insulation, it may not be enough to be doing much. A
well-insulated roof, on the other hand, can almost negate the need for either
mechanical system and certainly drastically reduce your heating and cooling
needs.”
The material you choose will depend heavily on the type of house you have and
the climate you live in. Today there is a vast range of insulation solutions
form home foam insulation and cellulose insulation to simpler options like
fiberglass or cotton batting. Whether the insulation is for the roof or your walls the experts at GBA reminds
us of the following rules of thumb, “You can’t stop the heat but you can slow it down.” Also, “More insulation is better, to a point.”
According to GBA, heat always moves from hot areas to cold areas. In summer,
exterior heat will flow toward the cooler interior of a home. In winter,
interior heat will flow toward the exterior. “The role of insulation is to slow this heat flow. In general, thicker insulation
is more effective than thinner insulation. Many energy consultants have
proposed the following rule of thumb: The R-value of insulation installed in a
green building should be about twice the code minimum. This is, of course, a
guide to planning rather than a hard-and-fast rule.” While it is true that doubling the thickness of a layer of insulation will
double the insulation’s R-value, cutting heat loss in half. The experts warn
not to double too much “Each time that the insulation layer is doubled in thickness, this rule applies.
The energy saved per year by doubling insulation from R-10 to R-20 will be
considerably more than the energy saved by doubling insulation from R-20 to
R-40 because of the law of diminishing returns.”
A Nice Dry Foundation
We all know that foundations in New York get wet, and when they get wet they
attract unwanted pests, mold, and fungi, which affects the energy efficiency of
the building while slowly leading to decay. The green defense is to work with
your surroundings to keep water from getting in, as well to promote drying of
surfaces that do get wet.
Gutters, for example, are a good place to start. According to Seville, “Gutters are a subject of debate among building professionals. When installed
properly and well maintained, gutters can be a great help in keeping water out
of a structure. When installation is compromised and maintenance is poor,
however, gutters can become a detriment, directing water into rather than away
from a structure.”
It is recommended that if your building has gutters they should be well
maintained to keep water from seeping into your building’s foundations. Suggestions for gutter installation or replacement include “the most durable and recyclable material available, such as aluminum or copper,
and make certain they are installed properly.” Additionally Seville recommends that “the downspouts should terminate at least five feet from the foundation walls.”
For those without gutters, one must look out for the moisture distribution in
the soil outside your buildings. Generally, rainwater is directed away from a
foundation by a sloped grade and carried off by a footing drain. However a
great deal of moisture still remains and is distributed throughout the soil.
According to the experts at GBA, “This soil moisture can wick into a foundation through capillarity. Capillarity
can move water to the top of a tree, so it shouldn’t be surprising that it can
transport water from the footing to the roof of a house. Without capillary
breaks, water is drawn into a foundation through the footing or the wall, and
will continue further up to drier concrete, where it can get into the framing.”
When moisture moves above ground into the framing, it may encounter cooler
surfaces and condense into liquid. If the wall can’t dry out, the liquid can
accumulate and support mold and rot. Professionals recommend insulating the
exterior of a foundation to block moisture and keep the concrete warm. A warm
inside surface means that humidity won’t condense into liquid that can cause
mold growth. Installing rigid or spray foam inside the foundation walls is
highly recommended to stop capillarity and condensation as it prevents warm air
from reaching the cool concrete.
Slow Steady Wins the Race
Whether you live in a large or small development, embarking on a “green upgrade” need not be costly or elaborate. A journey of a thousand miles starts with one
step. Today one of the easiest and cost effective methods is improving the
energy efficiency of your buildings. “Tightening the envelope” of your roof walls and foundations will lower energy usage resulting in greater
savings for the whole community. In this new age, greener and more sustainable
solutions seem the way to go.
J.M. Wilson is a freelance writer and a frequent contributor to The Cooperator.
Associate Editor Liam P. Cusack contributed to this article.
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