Tennessee Vernacular
Dating back to the late eighteenth century, natives of East
Tennessee established innovative design strategies that are
influential even among twenty-first century technology and
advancements in design. Early settlers truly understood the
challenges of Tennessee’s dual climate and built accordingly to
adapt to each extreme. These initial design practices have been
modified through the decades to accommodate modern architectural
demands, yet have remained as highly influential design concepts
today, symbolic of early civilizations’ design consciousness.
Timeline of Tennessee Vernacular
UT Zero
The University of Tennessee group, UT Zero, launched in the
Spring of 2008 as a multidisciplinary team seeking to develop new
technology for zero energy buildings. The UT Zero team is comprised
of the best students, faculty and professionals in architecture,
landscape architecture, electrical engineering, mechanical
engineering, interior design and graphic design that have worked
jointly to design and build the home of the future. Students and
faculty from various disciplines continue to collaborate on UT Zero
projects to promote zero net energy consumption and zero carbon
emission technology. It also showcases the latest innovations in
the areas of building materials, information technology, solar
energy, energy efficiency and home design to demonstrate
opportunities and methods for using sustainable energy resources.
UT Zero marks the beginning of our journey to the Solar Decathlon
as the awareness of new technological projects and the design of
zero energy homes for the future.
Prototype - Introducing
The initial goal of UT Zero was to take design development to
the next level and build a full-scale prototype, in the summer and
fall of 2009, to test the efficiency of its technology, energy
savings and design. The prototype is a 240 sq ft student built
project that applies cross-disciplinary education among students,
faculty and professionals. It is also a test facility for
construction methods, solar technology and human workflow as a
precursor to the technologies and methods that would be deployed
later in the Solar Decathlon Competition under the concept of
‘Living Light.’
Building the prototype provided students with hands-on
experience in advanced energy and construction systems. As a highly
visible education and outreach tool, it also introduced students to
an integrated design process where architectural aims and
engineering requirements could be evaluated simultaneously. With a
central location on the University of Tennessee campus, the
prototype has opened its door to countless visitors from the
campus, Knoxville and beyond.
Prototype
The design of the UT Zero prototype implements several design
strategies that were influential to the concept of ‘Living Light.’
The first strategy is orientation of the home on the site. Careful
siting of the building allows it to take advantage of southern
light while using walls and windows with high insulation values to
avoid unnecessary heat gain. The second strategy is the use of a
sunspace on the south facade to heat the interior in winter or act
as a buffer zone in the summer. Passive features, such as this, are
efficient in heating and cooling the home and are adopted from
early practices in East Tennessee architecture. The third strategy
integrates solar panels with reflective roofing and sun shading.
The translucent solar panels generate power by direct sunlight and
reflected light from the white roof membrane below. The solar
panels allow the house to function off grid, powering all its
electrical needs directly by day and from battery storage at
night.
The prototype designed and constructed by UT Zero is valuable in
its education, research and outreach potential. It is also symbolic
of The University of Tennessee’s commitment to a sustainable
future.
Concept
Light is a defining expression that powers all aspects of life.
Different interpretations of ‘living light’ have been divulged by
Team Tennessee and adopted as our design concept. Living light not
only relates to the sun, daylight and energy; it is a way of life
that actively engages each participant in a learning experience to
promote sustainable living.
While the concept is specific and unique to Team Tennessee’s
submission to the Solar Decathlon, living light is something that
has encompassed the architecture of East Tennessee since
pre-colonial times. Throughout Appalachian history, Tennessee
vernacular has proved its success in managing temperature change,
ventilation and daylight, making it extremely influential and
relevant in modern design practice.
The notion of living light can be interpreted many ways to
embody both the physical and conceptual essence of ‘light’. The
Solar Decathlon home illustrates the different aspects of this
concept. Living light means harvesting the sun’s energy, leaving a
small footprint on the environment, controlling light, maximizing
views, living compactly and allowing space to be flexible.
6 PARTS OF CONCEPT OF LIVING LIGHT
Harvesting the Sun’s Energy
Like the leaves of a plant, the integrated roof-top array
provides energy and shade for the home. The 9 kw array is comprised
of 72 hollow acrylic half-cylinder tubes 18 feet in length with the
flat of each tube angled at 30 degrees. Air drawn through the tubes
cools the photovoltaics and supplies tempered air as needed to an
internal heat pump with thermal storage tank and desiccant based
humidity control. A closed loop bring solution running within the
tubes provides preheated water to a heat pump water heater. LED
strips imbedded in the acrylic provide night lighting. The entire
system is assembled from readily available products and is designed
to be equally at home on the roof of the Living Light home or as a
retrofit to existing structures.
Leaving a Small Footprint
In addition to producing its own power, the house touches the
land lightly and is designed to take advantage of sustainable
materials and construction methods. The structural frame of the
home is a tubular truss comprising the center section of a
double-drop semi trailer. This allows for the majority of all
construction to take place in a controlled interior environment and
minimizes the need to expend energy re-erecting the structure on
site. To minimize carbon footprint, local wood is used extensively
as exterior and interior finish.
Giving People Control of Light, View and Ventilation
The north and south facades incorporate inner and outer glass
panes with motorized shades and horizontal blinds sandwiched in
between. Operable panels allow outside air to be admitted when
humidity is acceptable.
Maximizing Transparency and View
Inspired by the natural beauty of Southern Appalachia, the
Living Light team took as a challenge the creation of an energy
efficient living area connected spatially and visually to the
landscape outside. This was achieved through the use of fixed
aerogel panels on the north moveable thermal shades on the south
and multi-pane glazing throughout.
Living Compactly
The Living Light home is intended as a retreat from the visual
and physical clutter of the information Age while integrating
technology seamlessly into the design. Inspired by the cantilever
barns of Southern Appalachia, the floor plan organizes support
spaces into two dense cubes of program framing the open living
space in between. The greatest luxuries in the living Light home
are volume and light.
Allow Space to Transform With Function
Two cores organize the daily rituals of life. the public core
contains most kitchen appliances and is near the island. The
millwork of the public core can be entirely closed to hide its
function while the island extends to accommodate from two to eight
people. The opposite core contains the more private elements of bed
and bath. the adjacent entertainment center acts as a footboard and
defines the space of the bed when in use and folds out to become a
desk when the Murphy bed is stored.
Trailer System
The Living Light house is designed to actually be the trailer by
which it would be transported. For this to be possible, the house
had to be built with structural steel columns and beams. The
structural framing supports it while in transit and must sustain
the stresses en route. With this innovative transportation system,
the house can be transported in an easy and cost effective manner
and with minimal on-site construction assembly. Using this type of
system can be limiting in space planning and structural aspects of
design, however it has several benefits that ease transportation
and allow extra clearance on the road.
Facade
The dual core parti allows for maximum flexibility in spatial
planning as well as openness in the north and south facades. The
use of glass in these two facades offers the opportunity for
daylight and heat gain during winter months, as well as shading and
passive ventilation during the summer months. The use of wood in
the east and west cores respect the Tennessee vernacular and house
the private functions of the residence. The north and south facades
accommodate layers of devices used for privacy and shading. They
are sandwiched between exterior single pane glass and interior
triple pane glass. Next to the outside single pane of glass are the
daylight louver blinds used for controlling sunlight. Directly
behind these are the honeycomb shades used for privacy and
additional shading control.
The glazing follows a five-foot module, and each element of the
module is broken into one-foot four segments. This is to allow the
facade to operate in smaller segments, and helps in defining the
placement of intermediate structural elements. Furthermore, the
inside glass facade has one foot operable openings for cleaning
purposes.
The functions and operability of these facades are true to the
concept of ‘living light’ and increase the adaptability of the
house to a range of function and climate conditions.
(Function Diagram): Different shading systems provide the
ability to control light based on daily functions inside the house.
Shading systems are operated on the five-foot module to maximize
flexibility.
(Ventilation Diagram): Ventilation is active or passive
depending on the position of the one-foot operable panels in the
facade. In the open position, these panels allow fresh air to
circulate through the house, and in the closed position, air still
flows through the facade, and is exhausted back into the
environment.
(Sun Path Diagram): The sun is tracked at critical points of the
year from lightest to darkest: June 21st, march and September 21,
December 21st. The overhangs help shade the building in summer and
allow light in the winter. The cores block east and west light at
their harshest moments, controlling the quality of daylight
entering the home.
Spatial Planning
Spatial Planning of Living Light offers a strong focus on the
hierarchy of public and private functions. The basic parti consists
of two opposing wet cores with an open, central major space. One
first enters through the east core, housing the laundry and
mechanical rooms, and then proceeds to the open central area. The
spatial planning encourages circulation through the kitchen, living
space, sleeping quarters and finally to the opposite, more private
core.
The kitchen and dining area are primarily designed to serve the
two occupants that live in the house. The island houses an
induction cooktop with an oven underneath, but also provides table
space for two. The end of the table can swing up to extend the
table an additional 39 degrees to serve up to eight occupants. Wall
panels can extend out from the cabinetry as well to seal off the
kitchen service zone when not in use.
The seating in the living space is designed for a number of
configurations. The couch, two chairs, and two benches can be
arranged to define a smaller living area, while still maintaining a
fluid circulation through the house. A larger, linear arrangement
is possible that allows for more occupants to see the television in
the event of a movie night.
The cabinetry on the west end of the house is also
multifunctional. For the occupants in the living space, it houses
the television and entertainment center. On the opposite side, it
defines a small study area, with a desk surface that folds down.
The television itself can swivel around and also serve as the
computer monitor. The cubby at the back of the desk surface houses
a number of outlets for cord connections such as phone chargers,
speakers and computer devices. When the study is not in use, the
Murphy bed swings down from the opposite wall to occupy the same
space. The entertainment center at the foot of the bed now defines
the sleeping area for this configuration.
Mechanical
The mechanical systems utilize roof mounted equipment designed
to utilize the sun’s thermal energy. The tubular PV system allow
air to pass through them gaining or rejecting energy from the
atmosphere depending on the season. This preconditioned air can be
used for winter day heating, summer night cooling and for use in a
dehumidification system. Thermal solar collectors will provide a
method to heat a primary hot water tank and a secondary energy
storage tank. This hot water is used for domestic purposes and as a
primary conditioned air heating method. A heat recovery ventilator
will also be used to retain energy inside the house.
Electrical
The goal of the photovoltaic system is to integrate efficient
technology into a responsible architectural aesthetic. In addition,
the tubular PV system will allow the growth of the technology to
effectively integrate the house’s electrical, mechanical and
shading systems into a single element known as “The Hat” of the
house. This roof array can produce enough energy to power the
entire house (with a surplus), including appliances, water heating,
electronics and lighting.
Landscape
The Living Light landscape maximizes the green space, minimizes
the use of decking and still maintains a fluid circulation sequence
through ramps and platforms.
The site plan takes the outdoor space and divides it into the
north and south sides of the house. This stages the areas for the
decking, as well as the entry and exit sequence. The outdoor deck
space is offset to allow more gathering space on the east entrance
of the site. This creates a more private area on the west, exit end
of the house. The main outdoor areas are aligned with the houses
glazing system, providing pleasant views to the landscape from the
interior. The plants used in the landscape are grown mainly in
Tennessee and the southeast.
The landscape itself is a carefully engineered wetland that
allows roof drainage to flow through an internal draining system
down the east and west walls and circulate into the landscape on
the south and north side of the site. The water then filters
through each raised zone of the landscape and culminates in holding
tanks located underneath the deck.
The deck supports allow the panels to be installed quickly and
easily on any planar surface. They are made of plastic which can
withstand most climatic conditions. There are both fixed and height
adjustable supports. Leveling disks are available to adjust the
height of one or more sectors of the supports.
