UNIVERSITY OF FLORENCE
FACULTY OF ARCHITECTURE
DEPARTMENT OF TECHNOLOGY AND DESIGN
MASTER’S
THESIS IN ARCHITECTURE
2003 - 2004
DAYLIGHT
RESPONSIVE DESIGN
The improvement of the daylighting and artificial lighting conditions in the library of the Faculty of Architecture, University of Florence
ADVISER:
PROF. MARCO SALA
·
Abstract:
This dissertation focuses on the
application of an integrated daylight and artificial light system and especially
attempts to
evaluate the quality of lighting in the present state of an existence library
and suggests some alternative design strategies to improve it.
·
Hypothesis:
As
it is said before, the hypothesis is that:
The
lighting system in the library building does not function as intended because it
does not respond to the variable lighting conditions nor to the occupant needs
and satisfaction.
The
specific questions are proposed to investigate in order to gather information
for this hypothesis:
·
What is the distribution of
illumination on the desks?
·
What is the lighting power
density in the space, and how does it compare with the standard for the
libraries?
·
How far does daylight
penetrate into the space?
·
How is
daylight used to define zones and to organize movement through the Library?
·
What is the pattern of
electrical lighting use at the interior zone? What is the
pattern of use for
typical task lighting?
·
Is artificial
lighting configured and scheduled to supplement daylight?
·
Do the occupants perceive
glare at their workspace?
·
How much energy does the
lighting use?
·
What are the occupants’
perceptions of the library space and its present lighting condition?
·
Evaluation Methods and Equipment:
The
evaluation of the library lighting condition has been fulfilled through three
particular methods: Field measurement, simulation and user survey.
To
test this hypothesis, I followed a systematic procedure to evaluate the effects
of light in the library. The procedure included collection of raw data,
observation of how light patterns in the rooms affected the displays, and
evaluation of the occupancy of the room during various times of day and the
visual comfort during those times. Then I compared the results to the standards
set by the Illumination Engineering
Society (IES) or other available
standards. The steps taken in this phase are:
· Step 1:
The decision to focus on lighting
has been made after a preliminary visit to the library building, where
preliminary measurements and general impressions of the space have been
gathered. Hypothesizing that the lighting conditions, both electrical and
daylighting, are inappropriate for the activities typically performed in the
library, I began to tackle the different questions and take final measurements
for the study. Five study halls were selected as the location for most of the
measurements because of accessibility and least disturbance to the library work
activities.
·
Step 2:
Illuminance levels at 85cm high desk planes and the height of the book shelves were measured in lux with a handheld light meter to gather numerical illuminance data and modify a virtual 3D model, hoping to obtain a simulation that be near to the present state. The illuminance measurements became the basis to create isolux contour maps of the rooms and for zoning of the library spaces. The acquired data then were compared to the available lighting standards.
·
Step 3:
I
engaged in the activities typical of the library to observe the appropriateness
of the lighting conditions and brightness ratio during various times of the day.
The variable weather created an opportunity to witness
the performance of the integrated lighting scheme during both overcast and sunny
sky conditions. After a complete
photographing and surveying of the intended spaces and through the measurements,
I calculated the brightness ratio and luminance levels and compared them to the
lighting guides recommendations.
·
Step 4:
All lamps of the
present lighting system of the library were counted and classified, and the
wattage on the library floor in each zone was recorded. By adding up the total
lamps wattage used in all zones and dividing it by the square meter, the
lighting power density used on the library floor was estimated and compared to
the guidelines.
A
systematic survey of the users' attitudes to the indoor environment can help to
understand the merits and problems of present lighting system and controls as
adapted to the specific building and the conditions created by the building
design and the use of the building. Dissatisfaction expressed should be used to
try to understand where and why problems are found. In this way potential
changes can be made to improve the indoor environment. In summery, a post
occupancy evaluation (POE) of the building indicates how successful the lighting
system is, where the problems are, and, to some extent, how the performance can
be improved.
I surveyed the library users’ perceptions of lighting quality, visual comfort and other environmental parameters. A questionnaire was composed and handed out among the students. It was an opportunity for the library frequent users to comment on the lighting condition, directly. This survey leads to lessons to be learned about the successes and shortcomings of the present lighting system of the library.
Findings,
which have been obtained through the measurements, simulation and survey,
confirm the proposed hypothesis, showing that the present lighting conditions,
both electrical and daylighting, are inappropriate for the activities typically
performed in the library space.
The
illuminance level on the desks and among the stacks is the minimum level, which
is recommended by lighting guides and in some parts of the library falls even
below that. There are potential glare sources and the contribution of daylight
to illuminate the study halls is low. Since all lights are controlled manually,
electrical energy is wasted by little possibilities to adjust light sources
relative to need and daylight. Moreover, in some parts of the library, the
geometry and position of the furnishings appeared to hinder the penetration of
daylight from the windows. All in all, the motivation for the development of a
new lighting system is the disadvantages of the currently existing system.
·
Solutions
When
a building is completed it is critical to periodically evaluate how its lighting
system work to insure its maximum performance. An initial post-installation
check (commissioning) and regularly testing of the equipment can
significantly improve lighting system performance. When considering lighting
design in a library, the lighting system must have flexibility to satisfy
individual preferences and control, yet produce energy efficient and good
lighting quality for a variety of tasks.
In
this dissertation, an alternative is proposed in support of a daylight and
artificial lighting component (3M light pipes system) in order to improve the
library lighting condition, providing adequate light for desks, computer
stations and book stacks. Spatial
and furniture arrangement, material’s
colour and luminance balance are
modified and new local and global lighting are
defined based on
the zoning of the light level and through an integrated approach.
| Home |