Vertical Greenery Systems Research Papers

Improving Thermal Comfort through Vertical Greeneries in Transitional Spaces for the Tropical Climate: A Review

2017, Journal of Engineering Technology (JET)

This paper reviews the potential of transitional space in building for improving thermal comfort by using Vertical Greeneries System (VGS). Transitional space could be defined as a space that is indirectly occupied, located in between the... more

Figure 1. Types of transitional space [4], [12] As stated previously, green spaces are rapidly decreasing caused by the development of the properties and infrastructures in the urban area. Due to that issue, applying vertical greeneries on building are one of the promising solutions to this matter, where people who live and work in building need the presence of greeneries as a restorative element. Although the space is limited, usable spaces in building could be maximised with the best method to obtain a cost-effective and easy maintenance greenery systems. Transitional space could be an alternative location for applying both horizontal and vertical greenery systems. In general, transitional space or transient space could be defined as a buffer space, or spaces in between the interior and exterior environment as in Figure 1 (a-f). This area could be the entrance canopies, foyers, lift lobbies, corridors, and stairwells of a building, which is commonly used for communal areas. In office building, transitional space is commonly used as a restorative area for the occupants to take break during the working hours. This could help to reduce the work-related stress load as well as to improve their psychological well- being during the office hours [13]. Referring from Pitts and Jasmi [12], transitional space is not directly occupied by any major activities in the building however it has a large implication to occupants experience and building energy consumption. Generally, the space allocated for a transitional space in a building is up to 10% to 40% of total volume in different types of buildings and considered as one of the alternative means for optimising building performance. Although, it is not directly occupied, Hui and Jie [14] agreed that transitional space consumes more energy compare to other occupied parts of building of similar size when being conditioned to achieve the desirable thermal comfort for the users.

In general, VGS is classified based on their growing mechanisms, living wall and green facade [16]. Perini et al. [17] described on their research that living walls are commonly constructed from modular panel that contains natural or artificial growing medium (felt, foam, perlite, and mineral wool) on each of its panel and using the hydroponic system to provide the plants’ water and nutrition (refer to Figure 2). Due to the flexibility of the system in living walls, this system could accommodate single or multiple plant species, which are commonly low height perennials or herbaceous plants. Combining multiple plant species in one system could be more efficient in terms of the space used. In large scale, living wall is widely known as a microclimate modifier and it could be an artistic element due to the composition from the various plants use.

Figure 4. Schematic diagram of the multiple layer canopy (modified from Shahidan and Jones [18])

Figure 5. Variety of plant species used in VGS for building facade From the previous research, it has been known that plants with relatively dark coloured leaf potentially to absorb the solar heat increases significantly. Red coloured leafs are more effective in reducing air temperature [23]. Nevertheless, further studies on the leaf colour and thermal comfort must be considered in the future. Besides of its colour, leaf performance also depends on the amount of stoma particularly if applied in small spaces. It has been proven that small leaf plants like Lanceolate, Spatulae, and Linear is significantly owering the air temperature and relative humidity, including absorbing many types of chemical pollutants. While the wide eaf plants like Cordate and Elliptical are potentially reducing only the air temperature. It is also proved that by combining the leaf sizes, it will contribute a better thermal comfort for the occupants [30]. Moreover, the colourful foliage and the size variety on VGS can be considered as a living artwork that could enhance the quality of life [31]. Figure 5 shows the implementation of various foliage colours and sizes as the facade cover by growing the plants vertically. The combination of plants on each layer is believed to be effective in improving the microclimate, however there is a need to study regarding the most suitable plant species to be applied on each layer in order to maximise the effect of the greeneries application.

Figure 6. VGS application on transitional space currently applying VGS as well as other form of greeneries. This is also fulfilling the criteria for major green building rating tools. Beside as a climate modifier, VGS could be as a visual barrier, space divider, windbreaker, air filter, as well as a decorative element, as in Figure 6.

Figure 7. Schematic diagram of possible VGS application in balcony In spite of the limitation and privacy matter, balcony could be optimised for applying the VGS. However, there are many considerations for balcony planting since many people tend to utilise their balcony for domestic purposes. The view to the outdoor must be unobstructed since the visual access to the scenery outside the balcony could be a stress-reliever. Moreover, view is one of the selling points in property business. Figure 7 describes the most feasible location for applying VGS in balcony by considering the horizontal cone of vision in human. The VGS could be applied in both sides of the balcony, wall-mounted or freestanding. Since the space allocated is limited, the overall dimension of the VGS needs to be carefully calculated.

Figure 8. VGS application on building facade and transitional space To obtain the best performance from the VGS, the structure and maintenance of the VGS is another important issue. One of the prominent examples of VGS in the transitional space is in Entopia, Penang, as figured in Figure 8. The facade of the building are covered with felt pocket VGS. Different plant species are applied to create a beautiful sustainable work of art. The temperature surrounding the site is significantly cooler due to the moist felt and provides comfort for those who are nearby. Therefore it is proven that VGS could improve the thermal comfort.

Figure 9. Defects on felt pocket VGS application

SLE I. SUMMARY OF PLANTS USED AND THE BENEFITS

From the Table 1, it could be described that there are many native plants that are widely available in tropical countries could be applied for VGS. Beside ornamental plants, edible and medicinal plants are also possible to be grown vertically along with its benefits in improving the thermal comfort. Some plants, such as Winged bean (Psophocarpus tetrogonobulus) are also effective in carbon sequestering.

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Living walls in indoor environments

by Kan-chane Gunawardena

2019, Building and Environment

The warming climate, projected increase in frequency and severity of extreme heat events, and the long-established heat island phenomenon are all expected to exacerbate urban environmental thermal loading. Active means used for addressing... more

“igure 1. Vertical greening categories and some exemplar variants. "7 The background to vertical greening is addressed by reviews of exterior applications. ry This literature-base describes the approach as an intentional attempt to cover vertical built surfaces to a significant degree with plant life. Various authors have presented several terms to describe this principle, and a few have analysed common structures to distinguish categories and derived variants. Presently there is consensus on the distinct presence of two principal categories described as either ‘green facades’ or ‘living walls’, predicated on the location of the growth substrate [e.g. 2-4]. The growth medium in green facade features is either a limited ground area or contained in a planter that is located at the base of a host wall. The plants therefore root at the base and shoots grow up along the surface of the host wall; which is the reasoning for some authors describing such features as ‘ground-based’ greening [4]. Typical plants used for this purpose include climbers and wall-shrubs that represent a wide range in size, form, and phylogenetic origin. Presently, such ground-based green facades are experienced as exterior applications, while in interior environments vertical greening is dominated by living wall approaches.

This study principally considered the review of peer-reviewed journal publications from 1980 onward obtained through database keyword searches. These were then distilled to consider 44 papers from multidisciplinary backgrounds that addressed the study of performance aspects of any form of vertical greening, be it experimental, case study, or simulation-based. The studies are represented according to publication decade, principal methodology used, parameter representation, and plant types examined in Figure 2. This publication review was also supplemented by unstructured (with reference to general practice) and semi-structured (with reference to specific installations) interviews.

Figure 2. Breakdown of previous studies reviewed.

Figure 3. Atrium living wall at the David Attenborough Building in Cambridge. The relatively cooler surface presented by vegetation could be hypothesised to generate cold radiation effects and the formation of a ‘downdraught effect’ resulting from natural convective boundary layer flows along the surface. Such cold surface effects are well-documented in indoor environments, with studies mainly addressing occupant discomfort arising from proximity to cold window surfaces [35]. Manz & Frank [36] found such draughts to be critical for discomfort relative to reduced operative temperatures or radiation asymmetry, while Heiselberg [35] found discomfort to rapidly decrease within the first 2 m off the surface to highlight decay. The potential relevance of such surface temperature influences however has not been assessed in relation to vertical greening surfaces. With exterior conditions such effects are likely to be detectable only under stable conditions with very low wind velocities, as at higher velocities turbulent mixing could rapidly normalise such micro-scale effects. With indoor conditions however, there is greater potential for convective boundary layer flows to develop and cold radiation effects to be detected. Depending on the magnitude and pattern of decay, such influences could either threaten or benefit building occupant thermal comfort, and thus warrants further investigation. benefit building occupant thermal comfort, and thus warrants further investigation.

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Vertical Landscape and Its Effects on the Thermal and Acoustic Performance of the Building

by IAEME Publication

2016, IAEME PUBLICATION

Vertical landscape or living walls have been used in history and its references have been found in vernacular architecture. These walls not only have helped maintain the temperature by being good insulators to heat (cool in summers and... more

7.1 The Living walls as an Approach for a Healthy Urban Environment Architects Henry Browne and Borja Huidobro have built the National Insurance building in Las Condes, Santiago, Chile. The building has various eco-friendly features that made it a sustainable one. One of the features is its interior and exterior thermo panel’s vegetation that absorbs the heat of the sun. Another great green feature it has is its front wall that turns into a vegetable garden of around 3000 square meters vertical, wherein the plants changes into different looks over the years depending on the season as shown in figure. The proposal is based on the a few articles that have contributed and thrown light over this subject

Fig 2: Conceptual Drawing and Detail Vertical Section of Green Facade

The Genzyme Center is an example of a company doing the right things and this building was chosen as an AJA Top Ten Green Project for 2004. The goal of the design was to develop a building from the inside out, from the individual working environment to the overall complex structure of the building. There are eighteen gardens contributed to the green building concept. The building act as a living organism that would provide a connection to the outside through a visual connection with the outside, to look outside at the green and to bring that green into the building through the gardens and it was a high level of commitment to include the interior plants because it was the right thing to do for a green building as shown in figure. Interior planting in this building has mostly been met with a positive response. The air quality in the buildings is excellent, the shading and air-conditioning functions and also the aesthetic effect indoors are viewed positively. In administrative buildings, the number of staff off sick has decreased the individuality of the workplace plays a role here. high level of commitment to include the interior plants because it was the right thing to do for a green

7.2 Living walls — A Way to Green the Built Environment Authors: Susan Loh Fig 4: The Three Generic Green Wall Systems

Table 1: Maximum Acceptable Equivalent Sound Level 2.4 Ecological Balance Equivalent Sound Level at some common locations is indicated in the table below: Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount (biomass), number, and changing states of organisms within and among ecosystems. Biodiversity is the variety of life and its processes. It includes the variety of living organisms, the genetic differences among them, the communities and ecosystems in which they occur, and the ecological and revolutionary processes that keep them functioning, yet ever changing and adapting.

Table 3: Summary of Sound Absorption Coefficient However, due to the high cost of installation and maintenance, vertical greenery systems should not be chosen only for acoustics consideration. There are other wall facades like plastering and gypsum board which are more economic. Lastly, to obtain a reasonable insertion loss, care must be taken to ensure that there are no empty gaps within the vertical greenery system which allow transmission of noise without significant absorption or scattering. 2 dB to 3.9 dB. However not all vertical greenery systems exhibit a good noise reduction. From Table 2, VGS 2, 7, 5, 1 and 6 have a reduction of around 5—10 dB for low to middle frequency range (zone B). This acoustics reduction is perceptible or even clearly noticeable for human perception in the change of sound intensity. In the high frequencies (zone D), VGS 8 clearly outperforms the rest with a highest insertion loss of 8.8 dB. The rest of the vertical greenery systems have an insertion loss ranging from 9 dBto 3.9 dB.

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Absorción Acústica de Jardines Verticales Acoustic Absorption of Vertical Gardens

by Ana Rizzo La Malfa

2019, Elektron-Facultad de Ingenieria-Universidad de Buenos Aires

Vertical gardens, called "Greenery Systems", are a new tendency in modern constructions. They are applied increasingly more frequently on those buildings where energy and ecological considerations, environmentally friendly, are a... more

Vertical gardens, called "Greenery Systems", are a new tendency in modern constructions. They are applied increasingly more frequently on those buildings where energy and ecological considerations, environmentally friendly, are a priority. Some main features of these technologies are: thermal insulation improvement, environmental pollution filtering, acoustic absorption, water retention and a friendly aesthetic appearance. Vertical gardens can have dissimilar acoustic features because they depend on the kind of support, substrate and vegetation used. For this reason, nowadays, collected data are very diverse and incomplete and it is necessary to expand the data available to provide more alternatives with practical application. In this work, acoustic absorption of modular vertical greening was studied. Each module was developed with a rigid PVC base covered with fibrous material forming pockets, where the substrate and vegetation were placed. The plant species that were used are some of the most widespread ones in the region, in order to achieve a good adaptation and simple maintenance. Keywords: vertical greenery systems; acoustic absorption; noise reduction. Resumen-Los jardines verticales forman parte de una de las tendencias tecnológicas constructivas más modernas, conocidas como "Greenery Systems". Estas son aplicadas cada vez con más frecuencia en aquellas construcciones donde se priorizan consideraciones energéticas y ecológicas conciliables con el medio ambiente. Algunas de las características relevantes que presentan son la mejora del aislamiento térmico, el filtrado de polución ambiental, la absorción acústica, la retención de agua y una estética amigable. Los jardines verticales pueden poseer características acústicas disímiles entre ellos, debido a que dependen del tipo de soporte, sustrato y vegetación utilizada. Por ese motivo en la actualidad los datos existentes son muy variados e incompletos, y resulta necesario ampliar los mismos para disponer de mayores variantes constructivas con aplicación práctica. En este trabajo se estudió la absorción acústica de un sistema de jardín vertical del tipo modular. Cada módulo fue realizado sobre una base rígida de PVC, revestida de material fibroso, con el cual se conformaron bolsillos. En ellos se alojó el sustrato y la vegetación. Las especies vegetales que se utilizaron son algunas de las más difundidas en la región, a fin de lograr una buena adaptación y un mantenimiento sencillo. Palabras clave: jardines verticales; absorción acústica; reducción de ruido; greenery. I. INTRODUCCIÓN En las últimas décadas surge una situación extraordinaria en la historia de la humanidad como consecuencia del incremento significativo de la población mundial residente en áreas urbanas, situación que configura una matriz compleja de problemáticas tanto en el ambiente natural como en el construido. Dicha situación produce un conjunto de consecuencias en el aspecto sanitario, urbano y ambiental, entre las cuales se encuentra la contaminación acústica. En contrapartida, el desarrollo de "Greenery Systems" ha demostrado ser una solución apropiada para éstas problemáticas urbanas ya que, paulatinamente, se van reduciendo los costos de producción, mantenimiento, facilidad de colocación y además buscando cubrir las necesidades funcionales que requieren las viviendas en la actualidad. Los jardines verticales se presentan en diversos formatos ya sea en forma de cobertura intensiva o extensiva, parcial o total, compacta o modular, cada una de las cuales posee ventajas y desventajas respecto a los muros que se desea intervenir. La composición del jardín se conforma básicamente por una estructura que relaciona físicamente el muro con el sistema que contiene el sustrato, la vegetación y el sistema de riego. II. SISTEMA ESTUDIADO A. Módulos individuales El tipo de jardín vertical que se estudia es el "modular". Este jardín vertical, en su versión completa y con aplicación práctica, está compuesto por paneles individuales (módulos)

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