Attractive "Quiet" Courtyards: A Potential Modifier of Urban Residents' Responses to Road Traffic Noise?

Abstract

The present paper explores the influence of the physical environmental qualities of “quiet”. courtyards (degree of naturalness and utilization) on residents’ noise responses. A questionnaire study was conducted in urban residential areas with road-traffic noise exposure between LAeq,24h 58 to 68 dB at the most exposed façade. The dwellings had “quiet” indoor section/s and faced a “quiet” outdoor courtyard (LAeq,24h < 48 dB façade reflex included). Data were collected from 385 residents and four groups were formed based on sound-level categories (58–62 and 63–68 dB) and classification of the “quiet” courtyards into groups with low and high physical environmental quality. At both sound-level categories, the results indicate that access to high-quality “quiet” courtyards is associated with less noise annoyance and noise-disturbed outdoor activities among the residents. Compared to low-quality “quiet” courtyards, high-quality courtyards can function as an attractive restorative environment providing residents with a positive soundscape, opportunities for rest, relaxation and play as well as social relations that potentially reduce the adverse effects of noise. However, access to quietness and a high-quality courtyard can only compensate partly for high sound levels at façades facing the streets, thus, 16% and 29% were still noise annoyed at 58–62 and 63–68 dB, respectively. Implications of the “quiet”-side concept are discussed.

Characterizing urban areas with good sound quality: Development of a research protocol

“…[3,26,27] It is not clear yet, how large the variation in sounds should be and at what scale level this plays a role. Our conclusions can be illustrated by findings from Klaeboe et al [26,27] and the Swedish Soundscape Support to Health project: [23,24] By means of data gathered in surveys, Klaeboe et al [26,27] investigated whether the highest and lowest equivalent noise exposure values that were encountered at the respondents' dwellings or direct surroundings within a fixed distance (75 m), affected the reported annoyance due to road traffic noise. Based on their analyses, Klaeboe et al [26,27] concluded that a noisy neighborhood amplified the noise annoyance levels at home and the other way around; surprisingly, no indications were found that the availability of quiet(er) areas reduces road traffic noise annoyance.…”

“…[18,[20][21][22][23][24] Illustrative, is the finding of Nilsson and Berglund among visitors of Swedish city parks, that the sound quality of these parks with an L Aeq higher than 50 dB was perceived as a place with poor sound quality. [22] Participants in a study by Brambilla and Maffei, in Italian city parks, indicated that these sound levels matched a good sound quality.…”

The potential of building envelope greening to achieve quietness

“…In this numerical study, 3 types of measures are considered namely green roofs, green walls and vegetated low-height noise barriers positioned near roof edges. Such green measures further help to increase the visual attractiveness of the urban areas, which was shown to be important as well based on noise-related surveys [45].…”

“…In this numerical study, 3 types of measures are considered namely green roofs, green walls and vegetated low-height noise barriers positioned near roof edges. Such green measures further help to increase the visual attractiveness of the urban areas, which was shown to be important as well based on noise-related surveys [45].Low-height noise barriers were shown to be useful in road traffic noise applications at street level. This has been assessed by calculations with different numerical methods [46] [48].…”

Influence of rainfall on the noise shielding by a green roof

“…A green roof, in contrast to common rigid building envelopes, could therefore help making a facade really silent, on condition that the dominant sound path between source and (shielded) facade interacts with the green roof. This is important in the view of the so-called quiet side effect that has shown to reduce noise annoyance and noise-induced sleep disturbance [12][13] [14] [15].…”