Vivian Loftness: Resiliency, Regeneration, and Design Innovation
Publications
- Examining In Situ Acoustic Conditions for Enhanced Occupant Satisfaction in Contemporary Offices. by Indoor acoustic quality is one of the critical indicators for occupants' health, comfort, and productivity in contemporary office environments. Post-occupancy evaluation (POE) is usually employed to examine in situ acoustic measurements to ensure indoor acoustic quality. However, prevailing acoustic performance evaluation does not often consider the technical attributes of building systems (TABS) to holistically investigate the significant correlations between objective acoustic field measurements and subjective POE. As such, this study proposes to cross-examine in situ and perceived acoustic quality indices with TABS to quantify critical factors leading to enhanced occupant satisfaction. Statistical analyses suggest that technical building attributes can significantly influence occupants' acoustic satisfaction compared to sound levels recorded in contemporary offices. For instance, lowering the distributed noise level from above 40% to 2% can lead to an average 21% increase in occupant satisfaction. Ultimately, incorporating environmental measurements with physical building attributes from an occupant-centric perspective can uncover applicable design guidelines for achieving optimal acoustic quality with the highest occupant satisfaction.Publication Date: September 2022
- Using Machine Learning to Predict Retrofit Effects for a Commercial Building Portfolio byPublication Date: July 2021
- Detailed Record Title: Visual Environmental Parameters Associated with Visual Satisfaction in Multiple Office Buildings. by The visual environmental quality affects occupants' satisfaction, comfort, and health, but current studies rarely observe the specific design parameters in the visual environment that promotes occupant visual satisfaction which potentially improves overall environmental satisfaction. In this study, occupant satisfaction responses were collected via right-now survey, visual environment was measured, and building attributes were collected at 1394 workstations in 49 office buildings. This study 1) modeled the survey responses to discover which visual satisfaction responses have considerable impact on overall environmental satisfaction, and 2) assembled survey responses, building attributes, and measures to track which building attributes and environmental measures in the visual environment most affected subjective responses. In the first part, satisfaction with light level for computer work showed the biggest potential to raise overall environmental satisfaction in feature selection model. In the second part, two major parameters determining high satisfaction with light level for computer work were identified: percentage of workstations with seated view on a floor and ceiling light fixture type. Average satisfaction with light level for computer work can be improved by keeping percentage of workstations with seated view at least 35 % and installing ceiling light fixture types of 1' x 4' (30 cm x 120 cm).Call Number: Available OnlinePublication Date: 2020
- Multi-Season Assessment of Occupant Responses to Manual Shading and Dynamic Glass in a Workplace Environment. by The quality and controllability of the building façade can significantly contribute to building indoor environmental quality (IEQ) as well as the building's energy efficiency. Advanced technologies that support a façade's dynamic response to climatic changes, such as electrochromic (dynamic) glazing, have emerged as smart systems for IEQ and environmental sustainability. This research summarizes a four-season study of office workers moving from a floor with conventional blinds to work environments equipped with smart dynamic glazing which changes tint in response to weather condition to control daylighting levels. Multiple occupant environmental satisfaction surveys were conducted over one year to investigate differences in environmental and psychological responses to office settings with manual, and often static, facades as compared to offices with dynamic glazing. This research confirms that dynamic glazing significantly affected occupants' environmental satisfaction—enhancing individuals' environmental perceptions and psychological health—as compared to manual blinds. It reveals that the occupants in work environments with dynamic glazing reported 21.7% higher productivity gains, 24.8% increased ability to relax, 12.7% improved concentration, 25.3% better moods and 29.4% greater alertness than when they were in offices in the same building with manual shading devices. Also, the dynamic feature of the smart glazing showed a significant contribution to perceived work productivity while enhancing positive emotional responses by an average of 26%.Publication Date: January 2020
- Bio-Sensing and Reinforcement Learning approaches for Occupant-Centric Control. by Today, in most office buildings, indoor environment is regulated by HVAC systems with schedule-based rules. While prevalent, these schedule-based control strategies have often resulted in low satisfaction rates and energy waste. Researchers have applied many advanced methods in building controls to optimize occupant comfort and energy efficiency. However, it is still challenging to continuously integrate occupants’ personalized feedback into a control system that has learning ability. This study proposes a bio-sensing and multi-agent reinforcement learning (RL) control system comprised of multiple RL agents and a negotiator. The RL agents aim to optimize the thermal comfort of individual occupants based on their biological responses. The objective of the negotiator is to maximize the thermal comfort of a group of occupants in a shared environment and minimize energy consumption. A state-of-art reinforcement learning algorithm, double deep Q-learning, is implemented to train the control agents. The proposed control system is tested with three simulated occupants in a room modeled by EnergyPlus. The result shows that the proposed system can reach optimized thermal comfort after 112 simulation runs and improve the group thermal satisfaction by 59%, compared to the typical schedule-based setpoint control.Publication Date: 2019
- Elements That Contribute to Healthy Building Design. by The elements that contribute to a healthy building are multifactorial and can be discussed from different perspectives. OBJECTIVES: We present three viewpoints of designing a healthy building: the importance of sustainable development, the role of occupants for ensuring indoor air quality, and ongoing developments related to indoor finishes with low chemical emissions and good fungal resistance. DISCUSSION: Sustainable design rediscovers the social, environmental, and technical values of pedestrian and mixed-use communities, using existing infrastructures including "main streets" and small-town planning principles and recapturing indoor--outdoor relationships. This type of design introduces nonpolluting materials and assemblies with lower energy requirements and higher durability and recyclability. Building occupants play a major role in maintaining healthy indoor environments, especially in residences. Contributors to indoor air quality include cleaning habits and other behaviors; consumer products, furnishings, and appliances purchases, as well as where and how the occupants use them. Certification of consumer products and building materials as lowemitting products is a primary control measure for achieving good indoor air quality. Key products in this respect are office furniture, flooring, paints and coatings, adhesives and sealants, wall coverings, wood products, textiles, insulation, and cleaning products. Finishing materials play a major role in the quality of indoor air as related to moisture retention and mold growth. CONCLUSIONS: Sustainable design emphasizes the needs of infrastructure, lower energy consumption, durability, and recyclability. To ensure good indoor air quality, the product development for household use should aim to reduce material susceptibility to contaminants such as mold and should adopt consumer-oriented product labeling.Publication Date: June 2007
- Relationship Between Workplace Spatial Settings and Occupant-Perceived Support for Collaboration. by The increasingly collaborative nature of knowledge-based work requires workplaces to support both dynamic interactions and concentrated work, both of which are critical for collaboration performance. Given the prevalence of open-plan settings, this requirement has created new challenges for workplace design. Therefore, an understanding of the relationship between the spatial characteristics of workplace settings and the support for collaboration that is perceived by office workers is valuable and timely. Based on a study of 308 office workers in 27 office spaces, this article examines the relationship between a series of workplace spatial characteristics and the support that is perceived by the occupants for collaborations. The spatial characteristics that were examined included individual workstation characteristics that were derived from the literature and a new set of floor-plan layout variables that highlighted shared spaces that are critical for a variety of formal and informal collaboration activities at work. The key characteristics of workplace spatial settings that were associated with the support that the occupants perceived for collaboration were the distance from workstation to meeting space, the distance from workstation to shared service area, the distance from workstation to kitchen/coffee area, and the percentage of floor space that was dedicated to shared services and amenities.Publication Date: November 2011
- Post-occupancy evaluation of 20 office buildings as basis for future IEQ standards and guidelines by The design of modern work environments must anticipate high levels of spatial and technological change by providing responsive thermal and air quality delivery systems. Building occupants will require indoor environmental conditions to support computer-intensive activities as well as paper-based tasks. However, the current standards and guidelines for indoor environments were predominantly developed without consideration for these modern office variables. This limitation may lead to an occupant''s dissatisfaction with the indoor environmental quality (IEQ) as well as unnecessary energy use. With support from the U.S. General Services Administration, a research team at Carnegie Mellon University performed a wide range of post-occupancy evaluation studies in Federal office buildings across the U.S. over 7 years. IEQ conditions were determined with spot and continuous measurements, while the building occupants’ satisfaction with environmental attributes was surveyed simultaneously. Statistical analyses of over 400 workstations linked characteristics and environmental qualities to occupants’ satisfaction. The results challenged the validity of current IEQ standards and guidelines. Specific recommendations for improving current standards and guidelines are outlined here to help enhance environmental conditions in workplaces for future design projects. These include raising summer temperature set-points, separating task and ambient lighting requirements, and establishing minimum air flow rates at each workstation.Publication Date: March 2012
Sustainable Built Environments by Call Number: Available OnlineISBN: 1461458285Publication Date: 2014-07-08Sustainable design is a collective process whereby the built environment achieves unprecedented levels of ecological balance through new and retrofit construction, with the goal of long-term viability and humanization of architecture. Focusing on the environmental context, sustainable design merges the natural, minimum resource conditioning solutions of the past (daylight, solar heat, and natural ventilation) with the innovative technologies of the present.nbsp; The desired result is an integrated "intelligent" system that supports individual control with expert negotiation for resource consciousness. International experts in the field address the fundamental questions of sustainable design and landscape management: How should the sustainability of landscapes and buildings be evaluated? Which targets have to be set and which thresholds should not be exceeded? What forms of planning and governance structures exist and to what extent do they further the goals of sustainability?nbsp; Gathering 30 peer-reviewed entries from the Encyclopedia of Sustainability Science and Technology, Sustainable Built Environments provides comprehensive, multidisciplinary coverage of these issues and other aspects of sustainable building and landscape design.
