1. Introduction
Rapid urbanization, encompassing the economic, ecological, and sociological development process of cities, brings forth urban benefits alongside urban and environmental threats [
1]. The rapid depletion of natural and cultural resources, climate change, and urban pressures such as environmental pollution (air, water, noise) highlight the issues of urban resilience and sustainability [
2]. In the context of sustainability, which has become a global concern, the aim is to develop policies that enhance the quality of life for all individuals today and in the future by providing equal opportunities in cities and reducing the environmental impacts of all these efforts [
3,
4]. The lives of urban users directly influence the design of sustainability channels and products in accordance with sustainability principles, making it mandatory [
5].
Strategies for achieving sustainable development goals in cities are fundamentally based on the efficient use of raw materials and energy, as well as reducing/preventing their environmental impact [
6]. Sustainable cities provide a framework for urban development but also face environmental, local, social, cultural, and economic challenges [
7,
8]. Within this context, it is not possible identify a single suitable solution for sustainability in cities with different identities, resources, and characteristics [
9]. Therefore, each city needs unique urban planning, defining goals and objectives that enhance the quality of life for sustainability at macro- to microscales [
10].
Open green spaces, which are prominent among land uses that enhance the quality of life in urban areas, contribute significantly to sustainability due to their quality and usability [
11]. Urban open green spaces encompass urban equipment/furniture tailored to user needs, integrated into public spaces [
12]. Urban equipment is a crucial element that contributes to the livability of space and shape the identity of a city [
13]. This equipment has a systematic structure that ensures the integrity of the city and provides spatial uniqueness [
14]. Urban furniture holds significant importance for sustainable cities, being influenced by social, cultural, environmental, and economic factors [
15]. Seating units within urban equipment serve various purposes such as creating social spaces, relaxing, and gathering [
16]. Outdoor seating units with various designs commonly utilize materials such as concrete, wood, metal alloys, and plastics [
17]. Seating units that provide general usability in urban areas should be planned and designed with materials that are compatible with climatic conditions, allowing for adaptation, having long lifespans, and doing no harm to the environment in order to extend their lifespan within the framework of sustainability [
18].
Urban equipment has a lifecycle at the product–material scale before and after the design process. Additionally, they significantly impact urban quality of life and sustainability [
19]. This furniture is a significant part of urban design approaches and, supported by sustainable design strategies while addressing user needs, will contribute to future generations [
15]. Studies emphasizing the contribution of urban furniture to sustainability in sustainable urban designs are available [
20,
21]. These studies highlight the necessity of considering the environmental impact of materials/products in every aspect, from micro- to macroscales, such as urban furniture. In this context, emerging sustainable approaches adopt an understanding of where natural resources are efficiently used, ecosystems are preserved, and environmental impacts are reduced [
22]. In this regard, material choices and the raw material stage are crucial in the life cycle of urban equipment.
Sustainability gives rise to the concept of eco-design, which encompasses processes involving the assessment of and reduction in the environmental impacts of products or systems throughout their life cycle, shaping the design accordingly. Life cycle analysis can be defined as determining the environmental impacts of a design process from the raw material stage to transformation and disposal [
23,
24,
25,
26].
Rooted in the integrative impact of ecology and design, eco-design aims to create designs that do not harm the environment in any way during their use and return to nature, ensuring the sustainability of the production chain [
27,
28]. In eco-design, the identification of ecological impacts and consideration of environmental factors are essential from the early stages of product design, such as planning and conceptualization [
29,
30,
31]. Eco-design is shaped by seven main strategies covering the product’s life cycle [
32]. These strategies include low-impact material, reduction in material use, optimization of production techniques, optimization of distribution systems, reduction in impact during use, optimization of product lifetime, and optimization of end-of-life systems.
Life cycle assessment (LCA), which forms the basis of eco-design, is a technique that evaluates possible environmental impacts, such as energy usage and waste, in addition to production costs, as well as product usage and recycling [
33,
34]. In the approach adopted by low-carbon design philosophy, environmental impacts throughout the entire life cycle are considered. The product’s carbon footprint is revealed in life cycle design and analysis [
26]. In today’s discussions, particularly related to climate change, the importance of life cycle analysis is emphasized in connection with low-carbon design [
35]. “Life cycle analysis (LCA)” or “life cycle assessment (LCA)” is considered among the methodologies that assess the sustainability of products and is considered a suitable method from the urban scale to the furniture scale [
36]. Life cycle analysis encompasses five fundamental cycles: raw material acquisition, product manufacturing, product distribution and application, product use and maintenance, and the recycling or disposal of the product, covering the pre-use, in-use, and end-of-life stages of a product [
37,
38,
39,
40]. Additionally, life cycle analysis (LCA) occurs in four distinct stages: goal and scope definition, inventory analysis, impact analysis, and interpretation [
41,
42,
43]. In this context, the first step involves identifying the raw materials, energy, and water used throughout the product’s entire process, resulting in an inventory of environmental emissions. Based on the obtained data, the environmental impacts of inputs and outputs are evaluated, and in the final stage, systematic and comparative analyses are conducted with interpretations [
41,
44] The fundamental principle of life cycle analysis is to determine the environmental impacts of a product or substance, reduce harmful effects, and select environmentally and ecologically friendly products that cause minimal harm to the environment [
45,
46,
47]. Life cycle analysis has been standardized in the International Organization for Standardization (ISO) standards 14040 and 14044 [
48].
Life cycle analysis has various applications such as enhancing the planning and design processes of a product, making strategic decisions, integrating products into the eco-design process, and comparing products [
41]. Several tools and techniques are employed to reveal the environmental impacts of a product within the scope of eco-design. In this context, the Material-Energy-Toxicology (MET) matrix and analysis, with environmental indicators, have emerged as significant tools [
49,
50,
51]. Different software tools with various databases and interfaces, such as Simapro, GaBI, Umberto, and Ccalc, are utilized in the creation and evaluation of life cycle analysis [
52]. These software applications make significant contributions to the analysis process [
44]. Sustainability within the scope of urban planning, particularly in eco-design, highlights the need for life cycle analysis at both the urban and sub-scales. Selecting and analyzing products or materials in a way that minimizes ecological impact is crucial [
47,
53]. Therefore, all structural and vegetative areas within the city scope should be included in the sustainability process, and the environmental impacts of furniture that are overlooked at small scales should be identified, and necessary measures should be taken.
According to searches conducted on the Scopus and Web of Science databases, there are no eco-design studies specifically focused on benches in the literature. Although there are studies on sustainable urban equipment, there is a lack of research specifically focused on the life cycle analysis of this equipment. To the best of our knowledge, this article is the first attempt to evaluate the environmental effects on benches of a city using an LCA method.
In reviewing past studies, it has been observed that there are eco-design studies on the wood sector [
54] and furniture sector [
55,
56], sustainability studies on cities and urban spaces [
57,
58], and sustainability studies on urban equipment [
59,
60]. In this context, the current study aims to serve as a bridge among other studies and address questions such as “What are the environmental impacts of existing designs for benches as urban equipments? Is it possible to reduce the environmental impacts of these designs through eco-design methods?” The analysis conducted within the scope of this study calculated the current carbon footprints of 14 types of benches in the city, considering the materials. Carbon footprints were reduced by changing materials and reducing material diversity, and a bench model with a low carbon footprint was proposed by implementing ideas for reducing parts. With these studies, the main contribution of this article will be the eco-bench model proposals for cities created through eco-design studies conducted on existing designs. This study underscores the critical need to integrate life cycle analysis for the raw material stage into assessing the sustainability of urban furniture, particularly in the realm of urban furniture. This study only focused on the raw material stage of the life cycle of benches. Given that this study only addressed one stage of the life cycle, focusing on all stages of the life cycle in future studies would be appropriate and serve as a guide for further research. Focusing on seating elements in recreational areas and proposing eco-design solutions, it not only addresses a significant gap in the literature but also offers tangible strategies for reducing carbon footprints and advancing sustainable practices in coastal urban environments. This study, through its analysis of coastal urban furniture with eco-design, will provide a foundation for other similar works.
4. Conclusions
This research conducted in Rize evaluates seating elements within the city. This paper discusses the possibility of making seating elements sustainable in humid areas, coastal zones, and urban areas by making and implementing certain design decisions. Within the scope of this study, life cycle assessment (LCA) analysis was performed to measure the carbon footprint of existing seating elements in Rize for the raw material phase. Based on the analyses, gradual material changes were proposed and implemented with feedback to reduce the carbon footprint of existing seating units in the city. The focus was on materials that needed transformation to lower the carbon footprint values of the current seating units in the city. The discussion also addressed how much the carbon footprint could be reduced with the transformation of materials.
Once the materials to be used for seating units with a low carbon footprint were identified, ideas for part reduction were developed for creating new design models. The formation of new design models was carried out by implementing these reduction ideas. As a result, based on the presented solution proposals, emphasis was placed on how sustainable urban seating elements could be achieved.
As a result, it has been determined that the effective use of wood, a natural material, reduces the carbon footprint of sustainable urban seating elements. The findings suggesting the utilization of wood in urban furniture are corroborated by studies such as those conducted by Gabric et al. (2022) and Barcic et al. (2018) [
71,
72]. According to this study, it is necessary to avoid the use of materials such as concrete, polypropylene, granite, and iron structures as structural materials, as well as varnish and solvent paint as protective materials. In the first round, concrete and polypropylene materials were detected as a high-carbon-footprint material. Varnish, solvent paint, iron structure, and granite were determined to be high-carbon-footprint materials in the second round. Other studies have shown that reinforcements with concrete materials containing recycled aggregates are frequently used [
73]. While concrete is commonly used in urban furniture due to its durability and resistance to adverse weather conditions, efforts have been made to enhance its environmental sustainability. These include the addition of coal ash to concrete for urban furniture use [
74] and the development of cellular lightweight concrete designs for modular designs [
75]. However, based on the findings obtained in this study, concrete can be considered a material to be avoided from an environmental sustainability perspective. Designs with restricted use of metal as connection elements will contribute to environmental sustainability. Restricting and eliminating unnecessary components in the seating elements used for urban furniture is essential. However, the design model without legs presents a suitable design example for implementation everywhere within urban areas, while in landscape design, it serves as a good alternative solution for evaluating elevation differences.
The sustainability of urban seating elements can be optimized based on various environmental conditions through strategies such as the use of eco-friendly materials and the reduction in material usage, as seen in both the design model without legs and the design model with legs. As stated in the study by Yasar (2023) [
21], the sustainability of urban seating elements can be optimized for various environmental conditions through strategies such as the use of eco-friendly materials and the reduction in material usage. Additionally, reducing energy consumption for transportation and production, extending product lifespan to decrease the need for replacements, and designing end-of-life usability are all crucial strategies. Therefore, regardless of changes in climatic and geographical conditions, sustainable urban seating elements can be created by implementing these strategies.
However, within the scope of this study, an ecological approach has been taken primarily for the environmental impact dimension at the raw material stage for seating elements. Integration with the environment in the design of seating elements should not only be approached ecologically and for the raw material stage but also encompass all aspects of sustainability in the life cycle of designs, with universality being a forefront consideration. Additionally, the strength of moisture-prone materials, especially wood, in humid regions is a separate subject of investigation. In this sense, conducting studies based on moisture and climatic data, along with determining service life, will contribute to a clearer identification of the environmental impacts of seating elements.
In addition to environmental issues, universal design principles, which are components of sustainable design, are significant in the context of urban areas and urban designs and are used by the entire urban population without discrimination [
76]. In this regard, it would be appropriate for future studies to address sustainability in all its dimensions for seating elements, incorporating not only the ecological aspects of environmental impact but also the design element for human usability. In this regard, as highlighted by Spangenberg (2013), this will greatly improve the quality and sustainability of urban spaces [
77].
In addition to the scale considered within the scope of this study, other works in different scales addressing infrastructure and social deficiencies, unplanned settlements, parking and traffic issues, and deficiencies in pedestrian and bicycle paths are among the obstacles that could hinder urban sustainability [
78]. Because cities have a complex structure as a result of their development [
79], all of these components need to be made sustainable for the sustainability of the city.
Furthermore, sharing the findings of studies with urban stakeholders regardless of scale is of utmost importance. To achieve urban sustainability, it is necessary to develop local, national, and international policies that foster stakeholder collaboration to increase public awareness. Environmental standards and regulations hold a significant place in the policies to be developed within this scope. These standards should be prepared to encompass the entire life cycle of materials, from raw material extraction to recycling processes. Assessments should be made considering the environmental impact at the level of seating units, and sustainable products should be promoted when users and stakeholders are educated on this matter. Municipalities should engage in collaborative efforts with public and private institutions to increase awareness about sustainability through practical initiatives.
Environmental issues represent one of the greatest threats facing humanity, and tackling them requires comprehensive efforts at all scales, particularly focusing on urban sustainability. Success in addressing environmental problems can only be achieved through thorough work across all scales in cities. Therefore, starting from the equipment scale and extending to the city scale, a collaborative effort involving not only authorities or designers but also all stakeholders in the city is essential. Through such a collective effort, a sustainable environment can be provided for future generations.