Description
The recently completed (1996) Caplin Pavilion at the University of Virginia
School of Law is the centerpiece of a building ensemble which is similar
to the historic Academical Village. It is located between two parallel
linear buildings which define a central green space. Caplin Pavilion as
designed by Ayers, Saint Gross Architects from Baltimore is a centroidal
orthogonal space with both clerestory and perimeter glazing. It was designed
for multi-purpose activities; lectures, symposia, dinners, receptions and
meetings. The gross floor area is approximately 3400 square feet. The pavilion
is quite successful in hosting the wide array of functions with its open
plan, high ceilings, and wide expanse of glazing for abundant daylight.
 North
Facade of the Caplin Pavilion
Interior materials and their reflectances are as follows:
The insulated glass has a transmittance value of 64% |
 Plan
of Caplin Pavilion
Bound
on only one side by a corridor and service space, Caplin has three facades
through which to admit daylight with the primary one facing north. The
two side or secondary spaces differ from the main space in terms of a lower
ceiling height. Although two columns attempt to form an implied division,
the three spaces flow effortlessly into one another as does the light.
The primary means of admitting daylight is through a series of large windows
and doorways located in each of the three facades. The east and west facades
each have three large glass doors with transoms above while the primary
facade has three doorways in addition to a large window marking each side
space.
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 Ease/West
Section of Caplin Pavilion
In
addition to the windows located at ground level, lighting is also provided
through a series of clerestory windows and a lantern atop the pavilion.
At a height of approximately 33 feet above floor, the clerestory windows
function to bring light into the center of the space in order to balance
the light penetrating the exterior walls at ground level. There are three
relatively small size (3’ x 5’) clerestory windows facing in each of the
four directions.
In
addition, there is a tall narrow lantern above the clerestory at the pavilion’s
center.
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 Clerestory
Windows in Caplin Pavilion |
Daylighting measurements on a cloudy day reveal significant differences in average foot-candle levels between the east and west wings and the central space. Lighting levels throughout the pavilion rise during the course of the day. Solar orientation has no effect on the light levels due to the heavy cloud cover. The foot-candle levels in the east and west spaces are comfortable for reading throughout the day whereas those in the central space, varying between 5 and 15 foot-candles, are somewhat low for comfortable reading.
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 Interior
of Caplin Pavilion
On a sunny day in the central space, the light is less even than on cloudy days, with the highest light levels along the north, west and east edges and the lowest light levels next to the dark wood doors in the back of the room. Even those were above 50 foot-candles at the least, certainly enough for reading. The levels average around 80 foot-candles in the morning, drop to about 60 at noon, when the sun is high overhead and is not penetrating directly into the windows, then rise again in the afternoon. There are a few bright glare spots which result from direct rays shining in through the clerestory windows, and no direct sun comes in from the north side, which is the main facade exposure. It is hard to tell just how much the clerestory windows contribute to the light levels at the floor. However, they do contribute significantly to distributing the light levels in the central space. Daylighting in the east and west secondary spaces is a different situation. In the morning, the east side of the room is overflowing with light. There is glare in every window, resulting in veiling reflections and excessive contrast ratios. In the afternoon the situation is reversed. The west becomes unbearable and the east side is cool and evenly lit. At noon, the light levels in both spaces are high, but there are no glare problems. Most of these problems could have been avoided by not installing such
a highly polished wood floor and using a darker wood finish like the window
mullions. Most of the furniture is located in the most visually uncomfortable
east and west wings. By placing the furniture in the central most pleasant
space, the pavilion could be enriched with student activity on a daily
basis. The furniture could then be rearranged for special occasions.
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Analysis
Daylighting within Caplin Pavilion is quite successful. The abundance of large windows at ground level in combination with the high ceilings and uninterrupted floor plane allow for good distribution throughout. It is uncertain how much the clerestory windows contribute to the lighting at floor level, but they do serve successfully in lighting the lofty clerestory space, which ultimately enhances the overall lighting scheme. On a very bright sunny day, these clerestory windows sometimes create hot spots of glare on the floor which can be visually disruptive. The lantern atop the pavilion appears to exist purely as an aesthetic device. Its small size severely hinders the admittance of daylight. But it is a beautiful room even with its sunny day faults.
Subjective impressions were recorded both at the beginning and end of
the measurement day. The impressions for the cloudy day were as follows:
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Overall, the daylighting at Caplin Pavilion is better on cloudy days
than sunny days. On cloudy days the distribution of light within the space
is excellent; one can be comfortable anywhere in the room. Since there
are no direct rays of sunlight striking any of the surfaces, uncomfortable
glare and high contrast are not a problem.