Previous research has shown that merely calling an indoor environment environmentally certified will make people favor that environment over a conventional alternative. In this paper we explore whether this effect depends on participants deliberately comparing the two environments, and whether different reasons behind the certification influence the magnitude of the effect. In Experiment 1, participants in a between-subjects design assigned higher comfort ratings to an indoor environment that had been labeled "environmentally certified" in comparison with the exact same indoor environment that was unlabeled, suggesting that the effect arises even when participants do not compare the two environments when making their estimates. The results from Experiment 2 indicate that climate change mitigation (as the reason for the certification) is a slightly better trigger of the effect compared to climate change adaptation. The results suggest that studies on psychological effects of "green" buildings should experimentally control for the influence from participants' judgmental biases.

In this paper we argue that unsustainable behaviors often stem from a common averaging bias when people estimate the environmental impact of a set of environmentally friendly and less friendly objects or actions. In Experiment 1, we show that people believe that the total carbon footprint of a category of items (a community of buildings in this case) is lower, rather than higher, when environmentally friendly (“green” buildings) items are added to the category, a negative footprint illusion. Experiment 2 showed  that the carbon footprint estimate assigned to a category with a mix of environmentally friendly and less friendly objects (“green” and conventional  buildings) is the average of its subsets (the “green” buildings and the  conventional buildings, respectively), an averaging bias. A similar averaging  process may underpin estimates of the environmental impact of people's own actions, explaining why people believe that environmentally friendly actions can compensate for less friendly actions.

When ‘environmentally friendly’ items are added to a set of conventional items, people report that the total set will have a lower environmental impact even though the actual impact increases. One hypothesis is that this “negative footprint illusion” arises because people, who are susceptible to the illusion, lack necessary knowledge of the item’s actual environmental impact, perhaps coupled with a lack of mathematical skills. The study reported here addressed this hypothesis by recruiting participants (‘experts’) from a master’s program in energy systems, who thus have bachelor degrees in energy-related fields including academic training in mathematics. They were asked to estimate the number of trees needed to compensate for the environmental burden of two sets of buildings: One set of 150 buildings with conventional energy ratings and one set including the same 150 buildings but also 50 ‘green’ (energy-efficient) buildings. The experts reported that less trees were needed to compensate for the set with 150 conventional and 50 ‘green’ buildings compared to the set with only the 150 conventional buildings. This negative footprint illusion was as large in magnitude for the experts as it was for a group of novices without academic training in energy-related fields. We conclude that people are not immune to the negative footprint illusion even when they have the knowledge necessary to make accurate judgments.

Studies have found a preference bias for “environmentally friendly” or “green” artifacts and buildings. For example, indoor environments are more favorably viewed when the building is labeled/certified “green”, in comparison with one that is not labeled/certified, even though the two environments are actually identical. The present study explored how physical properties of the indoor environment (high vs. low temperature) and labeling (“green” vs. “conventional”) interacts in their effect on environment perception. Participants performed a series of tasks in four indoor environments with different labels (low vs. high carbon footprint) and different temperatures (23°C vs. 28°C). Label and temperature were manipulated orthogonally. The participants’ environmental concern was also measured. The environmentally concerned participant assigned higher thermal acceptance and satisfaction scores to the environment labeled “low carbon footprint” (i.e., “green” certified) compared to the environment labeled “high carbon footprint” (i.e., not “green” certified), but only in the cooler thermal environment. Environmentally indifferent participants’ perception of the environment did not differ depending on label or room temperature. The results suggest that a “green” label positively influence the perception of the indoor environment for occupants, but only when the temperature is within the acceptable range as proposed in guidelines for “green” buildings.

Introduction: Just calling a food product or an artifact “eco-friendly” is enough to make individuals believe that the products have superior features compared to an objectively identical alternative labeled conventional (e.g., Sörqvist et al. 2013). Research show that occupants are more comfortable in “green” buildings (Kim, Hwang, Lee & Corser, 2015), if these self-reports are influenced by the “green” label are still unclear. The purpose of this paper was to extend this eco-label effect even further, namely to buildings. Participants in the environmentally framed condition rated the room as more comfortable to the room framed as conventional. Practical implications and suggestions for future research are discussed.

Theoretical background: Research in environmental psychology have shown that people assign higher taste-ratings to a food-product that is labeled as eco-friendly compared to a conventional alternative, even though the two products are in fact identical. This preference bias has been shown with various products. For example coffee (Sörqvist et al. 2013), bananas (Sörqvist et al. 2015), wine (Wiedmann, 2014), and lamps (Sörqvist, Haga, Holmgren & Hansla, 2015). The purpose of this study was to investigate whether there exist a preference bias for “green” compared to conventional buildings

Method: Thirty five university students participated in the study (16 women), with a mean age of 28.06 years (SD = 10.22), ranging from 18 years to 62 years.

The study took place in two rooms, the participants were told that one room was run by an environmentally certified system, whereas the other room was run by a conventional system.

They were then asked to assign comfort ratings to both rooms.

A within design will be used with informational framing as the independent variable. The dependent variable was general comfort.

Results: The participants perceived the "green" room (M = 6.11, SD = 2.06) as more comfortable than the "conventional" room (M = 5.40, SD = 1.63), even though the two rooms were identical, t(34) = 2.03, p = .050.

Conclusion: Future studies investigating psychological benefits of “green” buildings should control for this preference bias, for example by not letting the participants know if the building is “green” or conventional. Also investigate potential methods regarding how to maximize this effect. 

As the demand for eco-friendly food—produced without pesticides and environmentally harmful chemicals—increases, the need to develop genetically modified (GM) organisms that are more resistant to parasites and other environmental crop threats may increase. Because of this, products labeled both “eco-friendly” and “genetically modified” could become commonly available on the market. In this paper, we explore—in a Swedish and a UK sample—the consequences of combining eco-labeling and GM-labeling to judgments of taste, health consequences and willingness to pay for raisins. Participants tasted and evaluated four categories of raisins (eco-labeled and GM-labeled; eco-labeled; GM-labeled; and neither eco-labeled nor GM-labeled). The results suggest that there is a cost associated with adding a GM-label to an eco-labeled product: The GM-label removes the psychological benefits of the eco-label. This negative effect of the GM-label was larger among Swedish participants in comparison with UK participants, because the magnitude of the positive effect of the eco-label was larger in the Swedish sample and, hence, the negative effects of the GM-label became more pronounced. The pattern was somewhat different depending on judgmental dimension. The cost associated with adding a GM-label was larger in estimates of taste and health than in estimates of willingness to pay, at least for the Swedish sample. The roles of individual differences in attitudes, environmental concern and socially desirable responding in relation to the label effects are discussed.

Some studies suggest that environmentally certified buildings may have psychological benefits for their occupants (e.g., higher perceived overall comfort and greater work place satisfaction). In my coming paper, I aim to investigate whether people will perceive a room as more comfortable and satisfactory following information regarding a bogus environmentally certification of the building in which the room are situated. The research procedure will consist of two conditions (i.e., one experimental and one control condition) and two measurements. Both conditions will first receive a questionnaire before a lecture regarding a survey exploring how students perceive the indoor environment in a classroom in which they are in, the questionnaire will also contain questions about environmental concern and pro-environmental. One month later the participants in the experimental condition will receive the exact same questionnaire but with complementary information telling them that the room has in the past month undergone certain interventions leading to an environmental certification, whereas the control condition will receive the exact same questionnaire again. The hypothesis is that the participants in the experimental condition will perceive the room as more comfortable compared to the control condition. An intriguing research question is if the participants in the experimental condition will score higher on pro-environmental behavior intentions and on environmental concern compared to the control condition, if this is the case it will have implications for previous studies showing that occupants of environmentally certified buildings have greater environmental concern compared to occupants in conventional buildings. Finally, the results will both methodologically and theoretically deepen the understanding about why “green” buildings can have psychological benefits.          

Visiting or viewing nature environments can have restorative psychological effects, while exposure to the built environment typically has less positive effects. A classic view is that this difference in restorative potential of nature and built environments depends on differences in the intrinsic characteristics of the stimuli. In addition, an evolutionary account is often assumed whereby restoration is believed to be a hardwired response to nature’s stimulus-features. Here, we propose the novel hypothesis that the restorative effects of a stimulus do not entirely depend on the stimulus-features per se, but also on the meaning that people assign to the stimulus. Participants conducted cognitively demanding tests prior to and after a brief pause. During the pause, the participants were exposed to an ambiguous sound consisting of pink noise with white noise interspersed. Participants in the “nature sound-source condition” were told that the sound originated from a nature scene with a waterfall; participants in the “industrial sound-source condition” were told that the sound originated from an industrial environment with machinery; and participants in the “control condition” were told nothing about the sound origin. Self-reported mental exhaustion showed that participants in the nature sound-source condition were more psychologically restored after the pause than participants in the industrial sound-source condition. One potential interpretation of the results is that restoration from nature experiences depends on learned, positive associations with nature; not only on hardwired responses shaped by evolution.

People tend to idealize eco-labeled products, but can eco-labeling have consequences for performance? To address this question, 48 university students were asked to undertake a color discrimination task adjacent to a desktop lamp that was either labeled “environmentally friendly” or “conventional” (although they were identical). The light of the lamp labeled “environmentally friendly” was rated as more comfortable. Notably, task performance was also better when the lamp was labeled “environmentally friendly”. Individual differences in environmental concern, but not pro-environmental consumer behavior and social desirability indexes, were related to the magnitude of the eco-label effect on performance. Whilst some previous studies have shown similar placebo-like effects of eco-labels on subjective ratings, this is the first study to show an eco-label effect for artifacts in the built environment on performance, and the first study to relate this effect to environmental concern. Psychological mechanisms that may underpin the eco-label effects are discussed.

People tend to idealize eco-labeled products, but can eco-labeling have consequences for performance To address this question, 48 university students were asked to undertake a color discrimination task adjacent to a desktop lamp that was either labeled “environmentally friendly” or “conventional” (although they were identical). The light of the lamp labeled “environmentally friendly” was rated as more comfortable. Notably, task performance was also better when the lamp was labeled “environmentally friendly”. Individual differences in environmental concern, but not pro-environmental consumer behavior and social desirability indexes, were related to the magnitude of the eco-label effect on performance. Whilst some previous studies have shown similar placebo-like effects of eco-labels on subjective ratings, this is the first study to show an eco-label effect for artifacts in the built environment on performance, and the first study to relate this effect to environmental concern. Psychological mechanisms that may underpin the eco-label effects are discussed.