Christiane Berger

Ms. Christiane Berger

Department of Building Physics and Building Ecology, TU Wien, Austria

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 March 2021 in Sustainability
Verified
Journal Article
Open access
PDF file
AMArdeshir Mahdavi
Ardeshir Mahdavi
CBChristiane Berger
Christiane Berger
HAHadeer Amin
Hadeer Amin
EAEleni Ampatzi
Eleni Ampatzi
RARune Korsholm Andersen
Rune Korsholm Andersen
SVSilke Verbruggen
Silke Verbruggen
Buildings’ expected (projected, simulated) energy use frequently does not match actual observations. This is commonly referred to as the energy performance gap. As such, many factors can contribute to the disagreement between expectations and observations. These include, for instance, uncertainty about buildings’ geometry, construction, systems, and weather conditions. However, the role of occupants in the energy performance gap has recently attracted much attention. It has even been suggested that occupants are the main cause of the energy performance gap. This, in turn, has led to suggestions that better models of occupant behavior can reduce the energy performance gap. The present effort aims at the review and evaluation of the evidence for such claims. To this end, a systematic literature search was conducted and relevant publications were identified and reviewed in detail. The review entailed the categorization of the studies according to the scope and strength of the evidence for occupants’ role in the energy performance gap. Moreover, deployed calculation and monitoring methods, normalization procedures, and reported causes and magnitudes of the energy performance gap were documented and evaluated. The results suggest that the role of occupants as significant or exclusive contributors to the energy performance gap is not sufficiently substantiated by evidence.

13 October 2020 in Sustainability
Verified
Journal Article
Open access
PDF file
AMArdeshir Mahdavi
Ardeshir Mahdavi
CBChristiane Berger
Christiane Berger
VBVeselina Bochukova
Veselina Bochukova
LBLeonidas Bourikas
Leonidas Bourikas
Runa HellwigRuna Hellwig
Runa Hellwig
MSMarcel Schweiker
Marcel Schweiker
A discussion of sustainability in architecture cannot be meaningfully carried out without the inclusion of most buildings’ central purpose, namely the provision of indoor environments that are accommodating of occupants’ needs and requirements. To this end, building designers and operators are expected to demonstrate compliance with codes and standards pertaining to indoor environmental quality (IEQ). However, the majority of conventional IEQ standards, codes, and guidelines have a single-domain character, in that they address IEQ in terms of a number of isolated domains (i.e., thermal, visual, acoustic, air quality). In this context, the present contribution explores the current state of multi-domain IEQ evaluation approaches and the necessary conditions for their further development and application. Toward this end, a number of common building rating schemes were selected and analyzed in detail. The results of this assessment imply the necessity of both short-term improvements of the existing schemes in terms of the transparency and plausibility of the applied point allocation and weighting strategies and the fundamental need for a deeper empirically grounded understanding of the nature of occupants’ perception of and behavior in the built environments.

21 April 2021 in Frontiers in Built Environment
Verified
Journal Article
Open access
PDF file
CBChristiane Berger
Christiane Berger
AMArdeshir Mahdavi
Ardeshir Mahdavi
The comfort requirements of occupants influence indoor-environmental factors and energy performance of buildings. Occupants are typically exposed to a multitude of indoor-environmental factors, including a variety of different thermal, auditory, visual, and air quality conditions. However, the bulk of past research and derivative indoor-environmental codes and standards concerning the comfort of occupants address the multiple indoor-environmental stimuli in isolation. Starting from a brief review of past research on multi-perceptual indoor-environmental assessments of occupants, the present study pursues an experimental approach to explore the potential cross-modal effects on the evaluation of indoor-environmental thermal, visual, and acoustic aspects. In this context, a laboratory space including two adjacent identical mock-up office rooms was used to conduct multi-aspect parametric studies with human participants. Different thermal, visual, and auditory conditions were maintained in these two units. In the course of the present study, 296 participants were exposed, on a short-term basis, to different combinations of thermal, visual, and auditory conditions. The experiments were intended to explore if the evaluation of one aspect of the indoor environment could be influenced by differences in the values pertaining to the other aspects. The experimental results are presented and discussed, including their limitations.

6 August 2021 in Energies
Verified
Journal Article
Open access
PDF file
AMArdeshir Mahdavi
Ardeshir Mahdavi
HTHelene Teufl
Helene Teufl
CBChristiane Berger
Christiane Berger
This paper presents an occupant-centric theory of buildings’ indoor-environmental control systems and their user interfaces. Buildings typically can have multiple devices and systems to maintain indoor-environmental conditions within certain ranges in order to meet occupants’ health and comfort requirements. Therefore, it is important to understand what those ranges are exactly, who defines them, and for whom. Health and comfort sciences offer some broad directions concerning desirable indoor conditions. These are typically formulated in various codes, standards, and guidelines in terms of target values or the set points of control variables. However, preferable conditions may differ at different times and for different individuals. Another question concerns the agency responsible for maintaining the preferred conditions. In some settings, conditions may be centrally controlled via the buildings’ automation systems, whereas in other settings, occupants might have the possibility to control their immediate surroundings. Given these qualifications, the objective of the present inquiry can be stated more precisely. We outline a human-ecologically inspired theory pertaining to the occupants’ perception of and interaction with a building’s indoor-environmental control systems and their user interfaces. Specifically, we explore the operationalization potential of the proposed theory as a compact assessment protocol for the evaluation of buildings’ responsiveness to occupants’ preferences. Initial experiences with the derivative protocol are promising. Nonetheless, in order to be fully applicable in practice, certain challenges must be addressed. These specifically include the need for more robust procedures toward the translation of occupants’ subjective judgments into quantitative evaluation scales.