by Shona O’Dea, Well AP, LEED AP BD+C,
DLR Group Building Performance Analyst
Within
the physical school environment, there is an entire world of things we cannot
see that influences the human experience of a space and a student’s ability to
perform. Pulling back the curtain on those elements equips everyone to better
understand – and embrace – a more holistic approach to district planning.
A
recent report from the World Green Building Council
concludes that indoor environmental quality (IEQ) can have a profound impact on
students’ cognitive function and performance, but optimizing the environmental
quality of schools involves much more than air sensors. A holistic master
planning process enables clients to think beyond a bare-bones conditions
assessment approach by expanding into a comprehensive plan for optimal building
performance, and one school district in Illinois agrees.
Barrington
School District 220 in Barrington, Illinois, partnered with DLR Group to lead a
district-wide facilities master plan to assess and improve learning environments
for its students and staff. DLR Group’s team began the process by documenting
12 schools and an administrative building within the district to qualify and quantify
holistic building performance. We translated our findings into a report card
that measured energy performance, thermal comfort, indoor air quality, visual
comfort, and acoustical satisfaction, a deliverable that is guiding future
decisions related to facilities and capital investments throughout the
district.
Baseline for Measurement
DLR
Group used a two-pronged approach to gather qualitative and quantitative information
related to IEQ at each building. To gather qualitative data, DLR Group issued a
district-wide IEQ satisfaction survey to all employees (including teachers,
administration, support, and maintenance), and collected 566 responses. These
responses were categorized into four key comfort factors: acoustic, air,
thermal, and visual to give the team a holistic understanding of the district’s
capital assets.
For
our quantitative efforts, the team placed IEQ equipment in representative
classrooms from each building, allowing us to observe “point-in-time” spot
measurements via monitors tracking temperature, relative humidity, CO2, PM2.5,
and TVOC over a data collection period of 72 hours per room. Additional qualitative
observations were recorded in workbooks, including:
- Do walls reach all the way up to the roof deck?
- What is the fraction of windows on the external walls?
- Are there any window dressings?
- Is the flooring material hard surface or soft surface?
DLR
Group also engaged teachers and students by utilizing on-site data logging
equipment throughout the process to create a personalized learning opportunity
for Barrington students. We partnered with students at each facility to move
data loggers between focus classrooms, following a defined schedule. Spot
measurements also recorded light levels, VOCs, and background decibel levels in
each focus classroom.
Once
the survey, workbooks, spot measurements, and logging were complete, DLR Group
compiled all data into a master grading tool or report card, along with the
basic site measurements and resource consumption results. The grading tool
algorithms, written for industry standard requirements, generated IEQ grades
for acoustical satisfaction, indoor air quality, thermal comfort, and visual
comfort.
Key Findings of the
Four Core Components
Acoustics
The
IEQ survey results identified a number of factors impacting acoustics,
including fans, air conditioning equipment, and furniture. During our classroom
observations at the high school, we noted teachers were limiting movement to
avoid disruption in adjacent spaces. Students also indicated that teachers were
not conducting classes as they desired due to concern that moving furniture
would disrupt nearby classes. Further testing revealed that furniture was
extremely heavy, and moving it caused the noise criteria inside that classroom
and adjacent classrooms to almost triple. From these results, the district was
able to demonstrate a need for new furniture that facilitates flexible teaching
and learning spaces in the high school.
Air Quality
Carbon
dioxide concentration often acts as a proxy for ventilation adequacy. The
concentration of carbon dioxide in outside air is approximately 400 PPM, and
industry standard internal thresholds recommend a maximum of 1200 PPM. Beyond
these levels, the brain begins to go into sleep mode, which can have a profound
impact on cognitive function.
The
necessary mechanical systems were in place to ventilate classrooms adequately,
and the air quality in this district received better-than-average results. Most
occupants did not record strong satisfaction or dissatisfaction with their air
quality, however stuffiness was the most popular complaint, especially in summer
months. All buildings tested for volatile organic compounds were at negligible
levels throughout. One building received an initially high reading but, on
further analysis, we determined the readings were conducted during an art fair
where the art supplies produced VOCs from off-gassing.
Our
assessment uncovered three buildings at approximately 3000 PPM, which exceeds
ASHRAE 62.1 Ventilation for Acceptable Indoor Air Quality Standards and
specifies 800 PPM plus ambient. The district immediately instituted a no-cost
solution by revising damper positions to ensure a CO2 level of no more than
1200 PPM at all buildings.
Daylighting
According
to the report by the World Green Building Council,
27 percent of U.S. schools have inadequate lighting. Light levels at Barrington
facilities were determined satisfactory, however some spaces generated higher
light levels than required due to replacement of fluorescents with efficient
LED bulbs.
Of
the 80 percent of respondents who have access to daylight, 80 percent are
satisfied with their visual environment. Areas with too much light are
scheduled for de-lamping, which will involve removing some of the LED bulbs
from light fixtures to return light levels to the illumination necessary for
the task conducted in the space. This solution also will result in energy
savings for Barrington.
Thermal
ASHRAE
Standard 55 Thermal Environmental Conditions for Human Occupancy recommends
operative temperatures range between 60- 80°F depending on factors such as occupants’
activity and clothing levels. Barrington levels fell within industry standards,
with an average setting at 68°F, however surveys results showed on average, 65
percent of occupants were dissatisfied with their thermal environments, with
more complaints in winter months due to drafts and uneven temperatures.
The
high school recorded a large range of variation in temperatures, initially attributed
to a number of additions to this building, and ranging ages of HVAC systems. On
further analysis, the HVAC systems were able to meet an optimal set point,
however that occurred at the end of the school day as students were heading
home for the evening. The district simply adjusted HVAC systems to warm up
earlier in the morning to improve comfort level at the high school.
In
other schools with a high number of thermal comfort complaints, temperature
readings hit the recommended set points. However, numerous elements also affect
thermal comfort, including humidity, air speed, and mean radiant temperature of
surfaces. Thermal imaging identified areas of missing or damaged insulation
causing temperature asymmetry; cold spots where moisture may have penetrated a
wall; thermal bridging issues at doorframes; or insufficient seals causing air
drafts. Long-term solutions for temperature asymmetry are being incorporated
into the District’s future capital planning.
Towards Transparency
This
comprehensive process helped Barrington officials make data-driven decisions on
how to best use its maintenance budgets, and plan for future capital
investments. Ultimately, while data, analysis, and recommendations play an
important role in any holistic master plan, the greater value may be found in
the deeper conversations that occur between agency and individual users. This level
of transparency and communication contributes to a positive relationship
between a school district and the local community it serves, and ultimately
improves the educational experience for all learners of all ages.
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