Asst. Prof. Dusan Licina, Ph.D.

School of Architecture, Civil and

Environmental Engineering

École polytechnique fédérale de Lausanne

dusan.licina@epfl.ch

Human-Oriented Built Environment LabWebsite: hobel.epfl.chTwitter: @licinadusan

INDOOR AIR QUALITY AND OCCUPANT

SATISFACTION IN GREEN CERTIFIED BUILDINGS

A Pilot Case Study

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Specific research areas

POLLUTANT DYNAMICS IN INDOOR AIR

HUMAN AIR POLLUTANT EXPOSURE

AIR QUALITY AND COMFORT IN BUILDINGS

SMART VENTILATION

AND IOT

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• Currently, there are more than 200 different green building

certification programs around the globe.

Around 1 million green certified projects

4

Current state of knowledge

• Few detailed studies on IEQ in green buildings

• Most (but not all) research shows that green buildings

outperform conventional ones in relation to IAQ and

reported satisfaction

• We need much more evidence to conclude this

• Little research has been conducted to determine whether and

how elements of green building programs improve IAQ

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New directions – designing for “health”

• Recent shift in design to emphasize the health and

experience of occupants – so called “Healthy Buildings”

• None of previous studies have investigated a green rating

scheme that focuses solely on “human health”, such as

WELL and LBC.

• WELL is the fastest growing green (“healthy”) building certification

program

(Source: https://v2.wellcertified.com/v/en/overview)

A separate talk about WELL starts in 40 min

By Veronika Licina

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Three case studies: “Before” and “After”

BREEAM

Winter 2019

WELL

Summer 2019

WELL

Winter 2020

RELOCATION

COMMON

Summer 2019

WELL

Winter 2020

WELL

Summer 2020

COMMON

Summer 2019

WELL

Winter 2020

WELL

Summer 2020

CA

SEST

UD

Y 1

CA

SEST

UD

Y 2

CA

SEST

UD

Y 3

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Case study 1: BREEAM vs WELL

BREEAM Building WELL Building

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Methods – Physical measurements

• Amsterdam, ~450 employees

• Physical measurements: 1 month per season

• Open space office, meeting room, private office

• Active: CO2, T, RH, size-resolved PM (0.3-10 µm)

• Passive: Individual VOCs, aldehydes

BREEAM

Winter 2019

WELL

Summer 2019

WELL

Winter 2020

RELOCATION

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Methods – Subjective surveys

very

satisfied

satisfied neutral dissatisfied

slightly

dissatisfiedvery

dissatisfied

slightly

satisfied

• Collected responses:

• 202 BREEAM (pre-relocation)

• 203 WELL (post-relocation)

• Questions about IEQ satisfaction/ perception/ preference,

building-related symptoms, self-reported productivity

• Statistics: Wilcoxon rank sum test (Mann-Whitney test)

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BREEAM vs WELL: CO2 and PM10

• Generally acceptable levels of CO2 and PM10 in both

buildings

Level of CO2 slightly lower in

WELL, owing to lower

occupancy density

Similar level of PM10 in the

two buildings

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BREEAM vs WELL: T and RH

No difference in T, despite

different seasons

Low RH level in BREEAM,

owing to seasonal effects

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BREEAM vs WELL: VOCs

Low VOC level in BREEAM-

certified building

Elevated level of “special

indoor”, especially Ethanol, 2-

(2-butoxyethoxy)-, acetate

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BREEAM vs WELL: TVOC & formaldehyde

Nearly order of magnitude

higher TVOC level in WELL

Higher level of formaldehyde

in WELL building

• Generally acceptable levels of formaldehyde, but TVOC

level in WELL exceeds German standard limit values

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BREEAM vs WELL: IAQ and Thermal Comfort

• Despite significantly lower level of TVOCs and formaldehyde

in BREEAM, employees were more satisfied with IAQ in

WELL-certified building

• Higher level of thermal comfort in WELL building

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1 2 3 4 5 6 7

Thermal comfort

Thermal comfort_W

Indoor air quality

Indoor air quality_W

Amout of l ight

Amout of l ight_W

Visual comfort

Visual comfort_W

Noise level

Noise level_W

Sound privacy

Sound privacy_W

Building maintenance

Building maintenance-W

Workplace

Workplace_W

Buildings

Buildings_W

ENVIRONMENTAL FACTORS

BUILDING

WORKPLACE***

BUILDING MAINTENANCE

SOUND PRIVACY***

NOISE LEVEL***

VISUAL COMFORT**

AMOUNT OF LIGHT

INDOOR AIRQUALITY***

THERMAL ENVIRONMENT***

-3 -2 -1 0 1 2 3VERY DISSATISFIED

VERY SATISFIED

BREEAM Building (n=202)

WELL Building (n=203)

MedianMean

v

1 2 3 4 5 6 7

Thermal comfort

Thermal comfort_W

Indoor air quality

Indoor air quality_W

Amout of l ight

Amout of l ight_W

Visual comfort

Visual comfort_W

Noise level

Noise level_W

Sound privacy

Sound privacy_W

Building maintenance

Building maintenance-W

Workplace

Workplace_W

Buildings

Buildings_W

ENVIRONMENTAL FACTORS

BUILDING

WORKPLACE***

BUILDING MAINTENANCE

SOUND PRIVACY***

NOISE LEVEL***

VISUAL COMFORT**

AMOUNT OF LIGHT

INDOOR AIRQUALITY***

THERMAL ENVIRONMENT***

-3 -2 -1 0 1 2 3VERY DISSATISFIED

VERY SATISFIED

BREEAM Building (n=202)

WELL Building (n=203)

MedianMean

v

• Satisfaction level with several other IEQ-related factors was

higher in WELL compared to BREEAM

BREEAM vs WELL: Other IEQ

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WELL* vs. all others

* Small

sample size

Contact: licinadusan@berkeley.edu17

The first ever study to examine WELL-certified building

No significant difference in CO2, T and particle levels

Indoor VOC level higher in WELL than in BREEAM

building

Occupants seem to be more satisfied in WELL than

BREEAM and other green-certified buildings

Need to conduct a broader research effort

We are currently investigating a larger sample of WELL

buildings

Summary of a case study

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Overview of building practices

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Discussion - Health performance pyramid

(Source: Licina et al. 2019, ASHRAE Journal)

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Challenges of green buildings – Challenge 1

(Sources: Licina et al. 2019, ASHRAE Journal; Teichman et al. 2015; Wei et al. 2015 BAE; LEED V4)

• Significant gap between relative emphasis on energy

related features and those that focus on occupant health

• A review of 100 green building case studies suggested that the

most prevalent energy saving strategies were observed in 80% of

green buildings, while high indoor air quality was reported in much

less buildings

• Low credit percentage

related to IAQ/IEQ

• LEED: now 20%,

it used to be 15%)

• All programs:

only ~7.5%

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Challenge 2: Performance testing/verification

(Sources: Licina et al. 2019, ASHRAE Journal)

• Most existing green building standards lack established

protocols for performance testing:

• The most rigorous IEQ verification practice is available in the

latest version of the WELL v2, but…

• For a 5’000 m2 project, 5 floors: 3 locations, once 1-hour of 1-

min measurements. Valid for 3 years!

• Episodic, resource-intensive, expert operator

• Early experiments with IoT sensing

• WELL v2 A08: Continuous monitoring once every 10 min, every

325 m2

• WELL v2 A07: Operable windows; monitoring once every hour,

acceptable within 4 km of a building

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Challenge 3: Lack of health metrics

(Sources: Licina et al. 2019, ASHRAE Journal)

• There is a lack of metrics to define leadership

• No established health-based indoor guidelines

• Most indoor guidelines are simply copy/paste of outdoor

guidelines

• The challenge is that our environmental health knowledge is

incomplete! So far only limited exposure data available with

fragmented data on health consequences…

Green buildings are often assumed (or claimed) to be

healthy and beneficial for occupants, but without the

performance data to support such claims/aspirations !

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Challenge 4: Knowledge on green buildings

(Sources: Licina et al. 2019, ASHRAE Journal;

Colton et al. 2015 American Journal of Public Health)

• Most (but not all) research shows that green buildings

outperform conventional ones in relation to measured and

perceived air quality and reported satisfaction

• We need much more evidence to conclude this, especially for health

Energy and Water Conservation

Occupancy Surveys

Indoor Environmental Quality

Direct Evidence for Health

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There is much to be achieved!

UnacceptableSick Buildings

SufficientTypical Buildings

EnrichingGreen Buildings

DesiredHealth and well-being