1. Introduction
The growth of populations and improvements in health and wellbeing (WB) are the driving forces of technological advancements [
1,
2,
3,
4]. A pertinent example of such progress is Thomas Newman’s (1664–1729) atmospheric steam engine [
5,
6] that revolutionised the state of production, construction, and consumption. However, the ultimate side effects (e.g., pollution, emissions, etc.) of these technological improvements [
7,
8,
9,
10,
11] contradict the aim of improving the health of both the planet and its inhabitants. Some of the effects are even irreversible, changing the Earth’s norms and primary systems and causing dramatic burdens, such as climate change. According to Benson [
12], humans have had more impact on Earth in the last 50 years than in the preceding two centuries, and the impact of humans even in the latter time period exceeds that of the entire period of human life on the planet. Current estimations [
13,
14] report that of Earth’s nine planetary boundaries [
15], four have been exceeded irreversibly [
16]—see
Figure 1.
Globally, technologies, including the building-industry-related ones, progressed in awe-inspiring ways [
17,
18,
19,
20,
21]. Furthermore, the building industry has been responsible for some of the most important [
22,
23] and pleasing achievements of civilisation (e.g., housing progression). In many cases, we can use buildings to learn about history and civilisations (e.g., Refs. [
22,
24,
25,
26,
27,
28]). At present, about 90% of our time is spent indoors [
29,
30]; therefore, buildings have recently become more significant than ever. The building industry affects the materials flow, the need for products, job markets, etc., on a massive scale. Therefore, the building industry plays an essential role in the economy [
31,
32], and even in politics, on a universal scale [
33,
34,
35]. The building industry is global capital intensive, providing jobs for more than 1,800,000 people, accounting for USD 1.7 trillion, and is involved in around 9% of the GDP growth. This is optimistic in one way and negative in the other. The positive aspect of the power of the building industry is its potential when developing new attitudes [
36] toward mature and healthy assets for the built environment or/and for nature, meaning the transition towards a sustainable, circular built environment will be significantly effective on a global scale. However, the negative side relates, for example, to the volume and scale of its impacts on health for both the environment and humans, either psychologically and mentally or physically. Consequently, the materialisation of the built environment, which is a major component, especially when considering the effects of the building industry on health, needs extra consideration, careful study, wise strategic decisions, and a holistic approach in the relevant planning and performance fields for integrations.
The construction sector is still highly dependent on abiotic resources [
37] and is greatly reliant on fossil-fuel-intensive materials [
38]; furthermore, approximately 40% of the globally extracted raw materials are used in the building industry. Scholars report that around 36% of the world’s energy (also see
Table 1) is consumed in the building industry [
39,
40,
41], causing an enormous amount of environmental burdens and emissions. Among all the above mentioned measures that impact health, a direct or indirect issue is CO
2 emissions (see
Table 1) caused by the building industry, which comprises 39% of the world’s energy-related CO
2 pollution [
42].
Yet, the IEA [
43] estimation employing recent principles shows that the CO
2 discharge will double by 2050. Moreover, the UN-IRP [
44] reports that from 1970 to 2017, material use increased by more than three times; furthermore, it will double by 2050. Thus, the construction sector consumes a large bulk of raw materials from the Earth and releases massive amounts of CO
2 in the air during these materials’ extraction, transportation, refinement, and production processes alone, causing an unhealthy environment in various ways. The harm that CO
2 causes to humans’ physical functioning includes headaches, fatigue, restlessness, difficulties in breathing, an increase in blood pressure and heart rate, and a considerable rise in respiratory minute volume, etc. With a 1% upsurge in carbon pollution, patients’ rates increase by 0.460%. Nevertheless, building materials’ effects on occupants’ health go beyond standard measures.
2. The Links between the Buildings and Health and Wellbeing
The subjects of health and building design are intertwined and almost impossible to disentangle. On a broad scale, many factors are linked to health, including air circulation, humidity measures, daylight, outside views, etc. (e.g., Refs. [
44,
45,
46,
47,
48,
49,
50,
51]), from the conceptualisation to the construction of a building; however, this strong subjective connection might be overlooked. The current research studies health on multiple scales, including macro- (i.e., urban and building levels), meso- (i.e., construction level), and microscales (i.e., materialisation level). Therefore, after a brief background on the macroscale, the mesoscale level is focused on in this paper, mainly concentrating on construction materialisation (CM)—see the schematic demonstration in
Figure 2.
On the macro level of the taxonomy here, the physical effects of buildings on the health of occupants have been vastly studied (e.g., Refs. [
52,
53,
54,
55,
56,
57,
58,
59,
60,
61,
62,
63,
64]. Moreover, even though it has not been studied as much as physical health, researchers worked on the influences of buildings on mental health (e.g., Refs. [
65,
66,
67,
68,
69,
70]. As the current research aimed to use a systematic approach as a component to achieve a healthy built environment, accomplishing a “programmable construction system” (PCS) was the goal, focusing on “programmable construction materials” (PCMs).
A literature study on houses associated with WB shows numerous works on categories rather than dwellings (on the macroscale of buildings), such as on retail buildings (e.g., Refs. [
71,
72,
73]), hospitals/care centres (e.g., Refs. [
74,
75,
76]), office buildings (e.g., Refs. [
70,
77,
78]), schools (e.g., Refs. [
30,
68,
79,
80]), etc. By classifying the literature from a different perspective, housing-sector-related research on WB also incorporates categories such as humidity balance, thermal insulation and comfort, air circulation and ventilation, lighting and view, energy usage and optimisation, etc. (e.g., Refs. [
22,
58,
59,
81,
82,
83,
84,
85]). Other housing-related WB classifications are observable in gender-based categories and age-oriented divisions. The latter belongs to user-oriented typologies and can be divided into two general groups of studies: care-houses and typical residences. Focusing on regular houses, examples of age-based research include investigations on health concerning housing for children (e.g., Refs. [
86,
87,
88,
89,
90]) and the WB of older adults with regard to housing (e.g., Refs. [
42,
91,
92,
93,
94,
95,
96]), etc.
2.1. Health and Housing
This section narrows the health and WB aspects associated with buildings as a whole down to the specific sector of housing, which is on the macroscale of the study.
The constitution of the World Health Organisation [
97] explains that: “Health is a state of complete physical, mental and social WB and not merely the absence of disease or infirmity”. In this regard, goal number 3 of the Sustainable Development Goals (SDGs) directly emphasises health, and most SDGs (e.g., no. 6, 7, etc.) indirectly underline it. Health is particularly crucial concerning houses, as they play an essential role in the health of the residents [
85]. Hence, houses are the first communal and private places for humans and are the most important [
98]. On the other hand, housing is a major sector of the building industry, as houses are globally the dominant type of building [
99]. Thus, for the housing sector, WB is extraordinarily essential, by which the industry, especially designers and planners as well as authorities, can invisibly improve the health of society. Designers of buildings, public and private spaces, and districts and urban areas build up the contexts and patterns of people’s lives, which influence society to the extent that they cause certain patterns and behaviours [
30,
100,
101,
102,
103,
104].
Designers’ decisions appear in their concepts and designs and then in the building itself. For instance, the spatial configurations decide where the user should sleep and how many blankets to use. Spatial configurations also dictate, for example, interactions with housemates [
104], what we wear indoors [
105,
106], the types and thicknesses of curtains, and interactions with the outdoors (e.g., size, location, and form of the windows) within our daily lives [
107,
108,
109,
110]. This influence is long-term and historical; it began at least from the development of the concept of formal cities [
111,
112,
113], which were known to exist from the era of the Hippodamus (498–408). Using pre-planned fortifications, central buildings, streets, pedestrian areas, and squares, planners such as Hippodamus forecasted directions for people’s social activities and lives, remarkably involving WB. In between the elements that are essential in the decisions that positively and negatively affect the WB of occupants, some stages are invisible to the eyes of occupants, including the construction phases. The latter means that construction systems (CSs) and the materialisation of houses from within the design processes to the end of service life affect the quality of occupants’ lives and WB [
76], at least with regard to the physical attributes. The built environment is a product of the building industry. According to Lawson [
114], designers, products, and users are interdependent. Yet, the built environment also affects mental health, which is even more complex than physical health. Firstly, mental health is less apparent and studied concerning the built environment. Secondly, most of the conducted studies concentrate on disabilities and problematic areas, such as the built environment for vulnerable members of society or people with particular diseases such as Alzheimer’s, Parkinson’s, and dementia (e.g., Refs. [
66,
115,
116,
117,
118,
119,
120,
121,
122,
123,
124,
125,
126]). Yet, the impacts of conventional construction systems (CCSs) and conventional construction materials (CCMs) on health (i.e., physical and mental WB) are rarely discussed. Therefore, the following section begins the relevant debates following the multiscale levels.
2.2. (un)Desirable Construction
The current section is a follow-up of the scales from the macroscale down to the meso level, concentrating on the links between construction (primarily for housing) and the users’ health and WB.
As mentioned above, built environment designers, as well as the CSs, influence the health of the users [
79,
114,
127,
128,
129,
130]. Based on the theory of subjective wellbeing, users’ mental health, which can initiate severe physical complications [
131,
132,
133,
134,
135,
136,
137,
138], is directly affected by their feelings [
139]. According to Diener [
140], subjective WB is life’s cognitive evaluation by an individual, the existence of positive feelings, and the absence of adverse emotions. Thus, as it relates to residents’ feelings, CCSs affect WB in various ways. Abundant examples of the effects on multiple levels are evident, such as impacts on a district by noise contaminations caused by construction-related activities [
141,
142,
143,
144,
145]. Yet, heavy construction projects’ consequences include exposure to dust, quarts, welding fumes, etc. [
146]. Similar examples include pollution caused by construction-related transportation, such as diesel exhaust, etc., which could even affect WB and satisfaction by interfering with a neighbourhood’s daily life [
147,
148,
149].
Further examples that cause severe adverse effects on WB (e.g., see
Table 2.) on an interdisciplinary scale include unknown and bizarre traffic. The latter may also involve mistrust, disconnect with the urban surface and texture due to the drastic changes, detachment caused by unfamiliar urban and neighbourhood views, etc. All the above mentioned issues relate to construction services and materials (i.e., transport, deposition, loading, etc.).
Furthermore, although he does not focus on health, Hill [
150] discusses the inefficiency of resource use as an added issue regarding materials; in this regard, Monahan et al. [
151] estimate that misdesigns and misplanning cause a direct export of unused materials to dumps at a rate of around 15%. Hence, De Schepper et al. [
152] suggest that approximately 850 million tons of waste are generated annually throughout demolition processes. In reality, waste is a new phase of the extracted materials from the resources, impacting the planet by extracting from the earth and dumping on its surface.
3. Analysis through a Brief Materials-Based Investigation in a Practical Case Study of CCMs: A Background Showing Cruciality for the PCMs
The current section aims to demonstrate the multiscale impacts of construction materials (CMs) on the health and WB of occupants of buildings and urban areas. Thus, this section focuses on the microscale of the taxonomy used in this research. It starts with a general introduction and then concentrates on the specific material, a case study of steel and TATA, and then an analysis of the influences on the multiple scales.
The formula of mass balance [
153] abstracts building materials and their proportions in various ways [
154]. As was also stated by Turgeon et al. [
155], the volume of petroleum people use in one day takes millions of years for the Earth to remake, and the same goes for sand and minerals. Is the Earth’s mass balance appropriately considered in the building industry? Steel manufacturing is a strong sector worldwide [
156]. As one of the top materials in conventional systems, steel is dramatically energy-intensive (see a comparison of the embodied energy in
Table 3), heavily relying on fossil-dependent sources. In a conventional steel production system, in 2018, it was found that, 1 ton of steel emits between 1.8 and 3.0 tons of CO
2. Steel production emissions make up more than 8% of the global [
157] emissions released into the air [
158]. The volume of emissions differs from one manufacturing system to the other [
159].
The irreversible use of the Earth’s capacity is a common issue regarding CCMs and is a crucial concern for the environment, which also applies to steel [
42]. With its main composition being of carbon and around 95% iron [
160], the material is primarily a product of iron ore (e.g., see the rising rate in
Figure 3), where coke and limestone also play critical roles. Iron ore is basically a mineral substance processed in blast furnaces [
161]. Hematite (with 69.9% iron), magnetite (with 72.4% iron), limonite (with 59.8% iron), and siderite (with 48.2% iron) are the most common types of ore [
160]. The extraction volume depends on the iron content but finding a few percent of the best components when mining natural resources is normal, even in the propertied ores [
162]. In principle, producing 1 ton of iron ore discharges more than 3 tons of tailings. Most of the world’s steel manufacturing systems depend on coal [
163]. The manufacturing process significantly relies on metallurgical coke, which requires sintering operations and coke making [
164].
3.1. A Short Overview of a Case Study: Following Health-Related Issues to the Source of CCSs
The effects of CCM-related manufacturing, such as steel’s influences on health, WB, and livelihood, go far beyond the materials discharged from the resources (i.e., almost irreversibly), such as pollution, energy consumption, etc. The steel manufacturer TISCO (Tata Iron and Steel Company Limited) in the Netherlands has recently attracted much attention in Europe. This investigation’s first phase was presented in the research update in June and September 2021 by the TU Eindhoven, and was also demonstrated at the ICSBE2-2021 [
165]. The Tata in Ijmuiden (
Figure 4) is the European branch of the company. It is not only the largest steel-producing cluster chain in the Netherlands but also the highest emitter of CO
2 in the country. Although it provides jobs for 9000 employees in the Netherlands (and 21,000 employees in Europe)—the positions of 30,000 more are linked with it—its emission of carcinogenic articles means it has a vast influence on the health of the inhabitants and the environment]. The CBS [
166] reported that GHG in Velsen (home to the TATA manufacturing company) is 42 times higher than the country’s average (5 kg CO
2/m²).
Hence, TATA Ijmuiden, similar to the entire steel industry [
167], continuously endangers its employees, who are also occupants of houses in the local neighbourhoods. Awolusi et al. [
167] emphasise that steel manufacturing is an unsafe working environment. In the case of TISCO Ijmuiden (TATA), in addition to the hot and uncomfortable operating conditions and other issues [
168] for the employees’ WB, the company impacts the environment in various ways (based on local observations in June 2021). Moreover, the inhabitants’ lives are disturbed and even put at risk by the smells, fumes, noises, lead and other unhealthy substance dispersions, etc. [
169]. More than 1100 individuals and corporations, including municipalities, repeatedly complained about the apparent dust and poisonous particles emitted; it is evident that even from a slight wind, Ijmuiden’s camping site is buried under black soot [
170]. According to RIVM [
171], people living in the region around TATA (e.g., Ijmuiden, Velsen, Beverwijk, Wijk aan Zee, etc.) suffer from headaches, dizziness, itching, shortness of breath, lung cancer, diabetes, and heart disease [
172] more often than the rest of the population. A large portion of the dramatic effects of TISCO relates to the CCSs; thus, so does the responsibility. Hence, based on studies, such as those by Boschman et al. [
173] and SJW (Shollenberger Januzzi & Wolfe) [
174], it is known that steel construction workers deal with an extensive range of dangerous factors during their working hours. They state that steelworkers are forced to suffer fatiguing hours, withstand strenuous situations, and endure threats that jeopardise their health [
175].
3.2. The Effects and Analysis
Observations in the current research and other studies, such as that of Awolusi et al. [
167], emphasise steel production as a high-risk working environment that continuously endangers its employees. Januzzi in [
174] categorise six common threats for steelworkers: (i) falls, (ii) heavy machinery, (iii) noise, (ix) toxins, (x) vibration, and (xi) heavy lifting. However, ILO [
176] identifies 10 excessively occurring dangers, as shown in
Table 4.
Thus, these manufacturers impact the health of society and endanger their workers [
175], which means CCMs are provided for the building industry in a harmful way. Hence, steel manufacturers also indirectly harm society’s WB and mental health. In principle, the physical and mental issues are also interrelated [
131,
133,
136,
177,
178].
Furthermore, the latter impacts of the steel industry (e.g., TISCO’s Tata Ijmuiden) also cause suspicion and doubt in the residents in the vicinity and thus apprehensive disconnections, and an unreliable and insecure urban life, and, therefore, unhappy societal and individual lives. Furthermore, critical but invisible issues [
179] are common in such cases, relating to the migration of friends, neighbours, relatives, family members, etc. [
180,
181,
182]. These transform an area into an untrustworthy living atmosphere that compromises happiness and subjective WB [
183,
184]. As was indicated before, many studies discuss subjective WB’s connections to urban life in various ways (e.g., Refs. [
179,
185,
186,
187,
188]). The emotions caused by these forced migrations affect the quality of life and WB of the remaining people, while the migrated members have to face new challenges. Considering the previous arguments about WB, the situation is very relevant to the statement made by Diener et al. [
132]. They state that subjective WB includes “frequently experiencing positive and adverse emotions and moods”, which has been defined as “affective experiences” by Hendriks et al. [
188]. Although the study by König et al. [
189] investigates the emotions, connections, diving factors, etc., on an international level, the results are similar to this local case of an industry-affected society. According to Allen et al. [
30], cities are the context of inhabitants’ lives. They state: “cities are all about people”. Thus, if people leave a place unhappily and due to the opposing forces of the life-threatening unhealthy activities of an industry, a city will not remain alive but will become a deserted place. Hence, the remaining people will be even more at risk due to added stresses and issues [
181] caused by the migration of members of their society. Social interaction improves health [
190,
191]; pollution prevents the remaining people from participating in outdoor activities and interactions, thus further damaging societal health. Linking the latter to the former through the case of TATA demonstrates the deduced logical evidence of the severity of the effects of the harmful production of CCMs on livelihood.
3.3. Review of Impacts on WB and Reformulation
Based on the severity of the issues in the mentioned case study (and many other circumstances), this section returns to a reformulation of the impacts of the building sector in general, aiming to establish an abstract, functional outcome schematically showing the harms of CCMs on health and WB throughout the production phases.
The building industry hugely compromises the planet and its inhabitants’ health [
42], primarily by its conventional handling of construction [
192,
193], especially in materialisations. In principle, steel’s health issues are similar to the other CCMs, such as in concrete production, masonry and brick manufacturing, etc. Worldwide examples include the destroyed communities around Delhi [
194], Istanbul, Mashhad [
195], and Dhaka [
196] caused by brick producers severely damaging the topsoil and landscape [
197], diminishing nature, causing flooding, etc. [
198]. A similar example can be seen in concrete and cement manufacturing in various locations, such as Sri Lanka [
199,
200,
201]. The generation of one centimetre of black soil takes more than 300 years [
202,
203]. Sand takes thousands (or even millions) of years to form [
204]. In addition to the significant scale of aggregate consumption, concrete is cement-dependent, releasing 1 ton of CO
2 per 1 ton of cement production. Yet, other polluting substances are dispersed in a large area in the vicinity depending on the local climate (e.g., around 3 km in Khamir Cement manufacturing). In the Hormozgan Cement Co. case study, before its environmental reform and filtrations, in addition to the enormous CO
2 volume (1.25 ton/1 ton cement), the vegetation in the 2.5 kilometres vicinity around the manufacturing site disappeared within five years.
In a broader perspective, conventional methods and systems of providing materials for construction, such as steel, harm WB in several ways. Thus, quality of life and WB diminishes due to the quantity of materials required. In addition, the effects on the Earth, as an indirect effect on lives and health (including threats to the construction workers’ health, such as welding fume inhalation, etc.), should be considered. The scheme in
Figure 5 also briefly demonstrates the hierarchy of these impacts in a very abstract view.
According to the Paris Agreement (2015), by 2030, 50% of the GHG (of 1990) should be removed from production systems. In practice, the building industry continuously uses abiotic CMs. In CCSs, far more impacts are generated during activities meant to serve users’ WB.
4. Healthy Construction in the Modern Building Industry
This section aims for the methodical use of sustainable and circular strategies. The goals here are to implement these strategies as checking criteria for health through an example of an uncomplicated toolkit.
Comprehensive strategies and thoughtful, immediate, and practical action plans are crucially required to make a difference in the challenges the building industry currently faces, and to avoid future adverse outcomes. Objective plans should be taken into practice to lubricate the transition using appropriate supportive tools, such as indicators, checklists, toolkits, etc. The idea is to enhance the resulting strategies and plans in the construction processes and ensure they are harmlessly practicable, aiming to achieve healthy, sustainable concepts. Therefore, to provide example toolkits for the healthy selection of materials, the following section presents formulations of the previous statements in practical applications.
4.1. Tools for Materials Selection for the Planet and Its Occupants
Based on previous practical and analytical discussions, and in line with the Paris Agreement (2015) and the SDGs [
205], sustainable concepts of the building processes for objective systems, including construction parts, should incorporate and prioritise the users’ health. Thus, the target for this objective system here is a “programmable CS” (PCS), dynamic CSs that are adjustable for health, biodiversity, economy, industrial ecology, etc., and safeguard a healthy forthcoming built environment. Similarly, Refs. [
113,
206] specified a long-term perspective as the only difference between liveability and sustainability. Thus, sustainability is a decent measure for the planet’s health and inhabitants.
Figure 6 also shows that occupants’ health can be ensured by examining and checking the sustainability pillars.
Regarding the pillars of sustainability, the economic situation of the users and the housing on a global scale are out of the scope of current research. However, the economic aspects predominantly related to the building industry incorporating the land use (i.e., indirectly), construction, materialisation, etc., that are relevant here can be checked concerning health within the scheme in
Figure 6. Environmental health checks also focus on the built environment and housing, which targets CMs. Following the path of PCSs, the latter will be in the form of programmable construction materials (PCMs). Returning to the sustainability pillars, the social WB of the scheme only checks the health and desire regarding the construction of houses. The summary of the processes of providing materials for the construction in
Figure 5 is applicable for analysing housing stocks as a significant portion of the building industry. Therefore, to base the PCSs for health on a broad scale, checking the impacts of the materials’ production processes with the three well-known components of sustainability could be an example of, and a summarised indicator for, the selection of materials. Programming PCMs for health is a vital consideration; thus, the mentioned checking tool is the health-oriented selection of PCMs, or HS-PCMs, shown in
Figure 7. This generative, simple, practical concept toolkit examines the health aspects of construction. It is easily developable into a sub-element.
The HS-PCMs is a general concept directly applicable to the mesoscale (i.e., construction). However, owing to its generative nature, it could also be further detailed for the application on the microscale (i.e., materials). In
Section 4.5., the proposed toolkit’s seven-stage application when evaluating health aspects of an example of an extreme case study, is briefly demonstrated (e.g., see
Section 4.5, Table 8).
To ensure the concept’s viability, it will also be tuned to circularity. Choosing the circular economy as the best way to battle climate change and take the strategies into action means it is the only way to make modern life healthy (see the pillars of the circular economy in
Figure 8). Julie Hirigoyen (2016), CEO of the UK Green Building Council, states that transferring the circular economy to the building industry will decrease resource consumption and adapt various applications while providing healthier living and workspaces. Similarly, Cheshire [
207] emphasises the healthy built environment as an advantage of the circular economy, resulting in significant economic returns for ownership costs. We provide examples here, depending on the sustainable solutions and support for transitions into a circular framework. The same method that health issues are previously checked with sustainability pillars in a sample case (e.g., scheme in
Figure 7) is also applicable to inspect them with the circular economy pillars (
Figure 8). A concept (to demonstrate the simplicity and effectiveness of practical applications) to make a toolkit out of a collection of these checking criteria is shown in the scheme of
Figure 9, which is similar to the HS-PCMS (the scheme in
Figure 5), which can be used with the circular economy.
Thriving emerging solutions include alternative CMs, evaluation criteria capable of public applications, and high-tech solutions for healthier PCMs based on renewable and sustainable sources.
4.2. Healthy Alternatives for the PCMs
This section concentrates on an appropriate compatible alternative that could be used as the third target material after steel and concrete (i.e., those currently dominant in the market) to facilitate transitions towards healthy PCMs. The alternative must be suitable for replacing CCMs on a vast scale. Bio-based materials have been implemented for use in sheltering humankind for our entire history [
208]. It is the source of environmentally friendly CMs that are primarily harmless [
209] and harvestable, only consuming a minor amount of energy [
210]. The platform of bio-based materials contains two main categories: biodegradable and bio-sourced materials.
Because of the sustainability aspects of these low-impact healthy materials, their bio-based applications in the building industry are advancing considerably. Examples include Eindhoven’s growing Pavillion, 2019; Hy-Fi tower of “The Living” in New York, 2014; HempHouse in Nashville, 2010; etc. Hence, their variety is also enlarging, going beyond the scope of this research. Therefore, only wood belonging to the second bio-based category is discussed here as an alternative replacement for abiotic materials on a public scale. Wood, in general applications, is the most widely used material [
211]. In addition to being the most sought after by humans [
212], this material comes from the most renewable resource on the planet [
213,
214,
215,
216,
217]. Therefore, it belongs to the very sustainable group of natural sources (e.g.,
Figure 10) due to its carbon sequestering and low energy consumption; compared with CCSs, it is very quickly renewable [
218]. The new generations of timber are lightweight, robust, durable [
215,
216], and applicable in prefabricated buildings. However, due to historical issues (e.g., centennial large city fires) [
219,
220,
221], timber was gradually removed from the modern construction market as a result of the disadvantages in its technical characteristics, as well as its other limitations [
222]. Nevertheless, new advancements in timber technology caused drastic developments, creating innovative high-tech timber [
223], which is also compatible with the cutting-edge technologies transferable for PCSs. However, applications in new houses are not equally growing with these advances (e.g., only 25% of the UK’s newly built houses are timber-based).
Health-Related Parameters for the Alternative PCMs
This study attempts to benefit from the effects of nature on mental and physical health, conducting research in construction-related directions. The connectivity of WB with the natural environment is a proven fact [
224,
225,
226,
227,
228,
229,
230,
231,
232]. In the built environment, biophilic, -mimetic, and other bio-inspired concepts that were first designed for the recovery of patients [
231], are famous examples of nature’s effectiveness on WB. Researchers at Michigan University observed that the productivity of office workers increased by 20% after spending one hour in nature [
230]. Hence, the U-M’s researchers also examined students’ test results and found that 20% of the students improved their scores after walking through nature [
230].
Further studies show similar effects on improving the memory of people diagnosed with depression, etc. Therefore, logically, as a part of nature, according to Dematte et al. [
221], timber is much closer to human feelings and sensations than any synthetics. Users’ emotions directly influence their mental states [
139]. In addition, the link between happiness and health has been excessively studied and proven (e.g., Refs. [
233,
234,
235,
236,
237,
238]). Similarly, Nyrud et al. [
239] and Nyrud et al. [
240] studied the influences of wood on patients’ health; they observed positive impacts. Hence, Cronhjort et al. [
241] examined the effect of timber on the interior of buildings; in blind testing, positive influences on participants’ feelings were the primary outcome.
The effectiveness of wood on people’s psychological health has also been investigated by Burnard et al. [
242] and Dematte et al. [
221]. Surprisingly, many researchers confirm that wood surfaces, compared with other CCSs, more effectively confine microbial growth and minimise microbial transmission [
243,
244,
245,
246,
247]. The study regarding the effects of exposed surfaces on hospital patients performed by Munir et al. [
247] proved that using wood in such applications reduces the requirements for chemicals and antimicrobic agents for daily cleaning. Based on the analysis of Alpert [
248], microbes on timber will face desiccation due to wood’s absorption properties. Hence, unhealthy and damaging microorganisms are withdrawn or even killed by the extractive components of wood’s tissue [
249]. Although the study of Munir et al. [
247] focuses on natural and untreated wood, it proves its effectiveness. They argue that due to wood’s hygroscopicity properties, microbes are stuck in this material and thus cannot contaminate food or other contacts. Hence, the absorption characteristics of timber trap microbes and prevent reproduction and colonisation [
250].
According to Munir et al. [
247], the porosity of wood, which was always discussed as a negative parameter in timber, is favourable for its hygroscopicity that causes unfavourable living conditions for microbes and even for some typical bacteria. Each of these natural materials resembles humankind’s affinity with uniqueness. However, inherent beauty features, cleanliness, and reactions towards microorganisms in different wood species vary [
247]. However, all timber embodies a certain level of hygroscopicity and antimicrobial chemicals to engage positively in users’ health. Therefore, if the properties and capacities of the emerging technologies allow for a massive market, this restorative material is an effective option for the transitions.
4.3. An Overview of the Qualities as Principles for an Alternative Healthy Materialisation
The effectiveness of wood in the modern CSs has been proven (e.g., Refs. [
241,
251,
252,
253,
254,
255]). For example, Jayalath et al. [
256], by conducting experimentations and analyses in three major cities in Australia on midrise buildings, approved the environmental efficiency of advanced mass timber over the CCSs. In principle, high-tech timber has provided two essential opportunities for the housing sector (and most other sectors).
Mass timber (MT): these are production techniques that can be applied on an extensive scale; they are crucial solutions for housing units, for example, for the demanding housing market of the Netherlands (see Ref. [
42] for analysis). The category of mass timber, which was primarily established as a framing style, currently uses large, dense wood panels for walls, floors, and roofs, and even in column construction. In addition to the latter, employing a combination of digital design, CNC processing, and other modern techniques, such as 3D printing and lasers, the market for mass timber is further enlarging and encompassing almost all types of buildings.
The engineering of mass timber (e.g., see examples of some high-tech mass timbers in
Table 5), in addition to the old systems, such as modular concepts developing in the novel and emerging techniques [
257], creates a new wave of advantages for the PCSs based on high-tech mass timber.
Healthy PCMs also require certain properties. Therefore, a summary of some technical characteristics and practical features for the new, high-tech mass timber, compared with conventional materials, is provided in
Table 6.
Some of the abovementioned mass timber technologies have already confirmed their unique qualities. For example, GluLam and CLT have been implemented even in large-volume construction and high-rise buildings (e.g., Dalston Lane in London, Forté in Melbourne, Brock Common in Vancouver, HoHo in Vienna, T3 in Minneapolis, the Kajstaden in Västerås Sweden, etc.). Therefore, mass timber can sustainably fulfil the current scale of demands for housing at a rapid pace with agility, sustainability, and resilience, which are crucial for a successful transition [
258]. Although mass production after the Industrial Revolution [
259] caused most of the adverse effects on the environment [
113,
260,
261,
262,
263,
264], mass timber is based on relatively quick renewable sources [
223,
265,
266,
267]. The historic obstacles were fire and decay. Fire has a long history regarding buildings [
222]. Naturally, wood decays in various ways, including through weathering, insect infestation [
268], and fungal decay [
269]. However, modern timbers have overcome the old complications [
270,
271].
Nevertheless, in addition to the study of Igarashi [
272] and Feldhoff [
273], which recognised the lobby in Japan’s construction market against sustainable products, Kaiser [
271] identifies the poor regulations that relate to the returning of wood into the building industry on a global scale. He emphasises the high qualities and potential of new generations of CLT that meet the building requirements [
271]. Studying the Swedish construction sector, Hemstrom et al. [
274] also show the necessity for some governmental regulation and intervention to accomplish successful innovative transitions. Similarly, in the Netherlands, new policies such as BENG 1, 2, and 3 with the TOjuli, functioning from 01.01.2021, tighten the advanced CS regulations to provide more room for the CCSs. Thus, the technical (tested in
Section 4.5.) and social (examined in
Section 4.4.) characteristics of the innovative renewable alternatives for CMs, such as timber for public use, do not seem to be adequately appreciated.
4.4. Practical Checking: A Sample to Examine the Societal Preferences
In addition to the interconnectivity of health and occupants’ satisfaction, the users’ desire is a critical priority for the PCSs concerning WB and the economy. Addressing health ensures the durability of a specific construction system (CS) or construction material (CM) in the market. Therefore, social preferences are considered a significant component of the objective PCMs’ establishment. In this regard, brief, abstract results from comprehensive research (see the subsequent investigation in Shahnoori et al. (2022)) are presented here. The PCMs are tools under a comprehensive strategy for healthy evolving CSs. To examine the method in various aspects, extensive questionnaires and interviews were conducted. Gradually, more than 750 users submitted their reactions; however, around 500 results were incorporated in this article due to time constraints. In the first phase of the field research, the questionnaires about the people’s interests in three materials (CMs), namely steel, concrete, and timber, were delivered without providing extra information about the characteristics of the CSs. However, some critical features of advanced mass timber were presented to the interviewees in the second round. The results towards timber dramatically and positively changed. The other noticeable difference between the two research rounds was the age classification. In the first round, older adults were the most common group, while all age groups were equal in the second round. Discussing the societal-related study in detail and its analytical arguments is beyond the current article’s scope. Therefore, only the summary of outcomes of the research on social interests is shown in
Table 7. A comparison of the male and female participants’ preferences for the same case is demonstrated in the chart in
Figure 11.
4.5. An Extreme Case of Application of the Proposed Alternative as a Demonstrative Example
Advanced mass timber techniques, such as the CLT (Cross Laminated Timber), GLM (Glue Laminated), LVL (Laminated Veneer Lumber), etc., demonstrate higher qualities than the CCMs. However, qualities are relative and should be comparatively evaluated. Hence, the advance of mass timber technologies is progressive but at a rather rapid pace. They come from renewable sources [
275]. Their carbon footprint is at least 50% lower than CCMs. Their life-cycle assessment and end-of-life scenario confirm their healthy advantages [
276,
277,
278,
279]. As an appropriate case of applied, sustainable, and healthy CMs, the Sara Cultural Centre is partly evaluated according to the PCMs (see
Table 8). The 76 m 20-story building is currently one of the world’s tallest timber buildings (i.e., the fourth tallest), containing GLM columns and CLT walls, and it is located in Skelleftea, Sweden. Constructed from 12,200 cubic meters of wood, it also uses carbon-neutral energy via solar panels, batteries, and a heat pump that works with electrical, water, and district heating. The fire compartment system (i.e., the charring capacity of wood) is also powered by renewable energy (White Arkitekter, 2021). Thanks to the wood structure, the carbon emissions for lighting and thermal comfort are less than 50% of the carbon sequestering in the construction. With more than 100 years of service life span, the building will continue sequestering carbon for more than 50 years (GCR, 2021). Similar cases such as the 85.4 m tall Mjøstårnet in Brumunddal, 100 km north Oslo, or the Treet Tower in Bergen (Damgårdsveien 99), are increasingly being developed across the globe.
Yet, with identical performance characteristics of the CLT compared with CSs, such as concrete, it is 80% lighter, affecting transportation, energy use, time and velocity, safety, etc. Hence, the mentioned CO2 reduction is natural and does not incorporate extra MAC (marginal abatement costs). In addition to the seismic performance and ductility of the joints, CLT and GLT do not transmit heat and cold, which disturb the indoor thermal balances.
As also shown in
Table 8, although the HS-PCM toolkit is at the concept level and early development stage, it is already applicable for a general evaluation of the health aspects of various phases of a construction case based on sustainability pillars.
5. Recapitulations and Discussions
This study involves a long-term commitment to researching users’ health connections to the construction systems (CSs) on multiple scales, further detailing, converging, developing, and focusing on construction materialisation (CM) for transitions toward a healthy, evolving, sustainable, and circular built environment.
Investigating the relationship between renewable materials such as timber and health shows that many categories in various disciplines are distinctive. On the construction level, most studies refer to the health of the structure (e.g., Refs. [
280,
281,
282]), the health issues of the construction workers [
173,
283,
284], or hazardous materials [
285,
286]. Thus, not much research focuses on the effects of renewable alternatives, such as timber-CMs, on the health of society and its users in a comprehensive view.
It has been discussed that mental and physical health and WB are intertwined, meaning that if the CSs compromise one, the other will be directly or indirectly affected. Examples of the possible influences of construction work on physical or mental health have been presented (e.g., noise, air, visual, etc.); and issues to be faced in the building industry have been reformulated. Emerging technologies should consider a covering and controlling umbrella for integrations and cautious actions to prevent the reoccurrence of side effects. It might be regarded that CCs could continue with the same conventions because other technologies solve pollution and other problems for health (e.g., unnatural carbon-capturing); however, from an inclusive perspective, the solutions might prove otherwise. Good examples are available in other fields too. A good case is the battle for reducing GHG using innovative systems such as carbon engineering techniques (i.e., using solid solutions to solve environmental challenges); methods such as direct air capture are also being developed. However, their primary requirements cause a new wave of issues, e.g., liquid solvent systems require a high temperature of up to 900 degrees, and the solid sorbent requires a temperature of more than 100 degrees to release carbon internally. Even ignoring their principles (which is almost impossible), such methods might be needed; however, they are not enough to prevent GHG and CO2 pollution.
Annually around 33,000,000,000 tons of energy-related CO
2 emitted in the air need to be addressed using integrated evolving concepts, valuable approaches, and undercover, appropriate, holistic strategies. The severe adverse effects of these CO
2 emissions on health have been previously indicated. Additionally, it is being recognised that levels of decision making and scores regarding the cognitive functioning of office workers increase in buildings with low-carbon concentrations. Similar deductions could be derived regarding housing. Thus, considering the two-fold responsibility of the building industry (i.e., the health of users and occupants and causing a large volume of pollution), the housing sector needs objective approaches and urgent solutions. Objectivity and programming are critical for the building industry and its product (i.e., the built environment). Tools such as PCMs, integrated into the sustainability strategy within the circular economy framework, are small but practical steps for CSs. With the latter, the implementation of high-tech mass timber as healthy PCMs, a comparatively fast and renewable source of materials, must spread globally while being studied for local needs and contexts. The latter has also been emphasised in the findings of Hetemaki et al. [
218]. The broad implementation of these new generations of renewable sources, such as mass timber, if backed up with sustainable sources, does not cause proportional adverse effects on health. Demolition and waste recycling and their relevant energy consumption, biodiversity, industrial ecology, etc., all fit in the sustainability and circular economy framework. A significant factor in relying on the high-tech products of mass timber (e.g., CLT, GLM, etc.) is their growing development trend and day-to-day progression towards characteristic optimisations and advancements.
This research, analogous to the study of Kuzman et al. [
222], found that municipality policies are not encouraging the use of wood structures—old systems are not drastically changed. Similar to the findings of Kaiser [
271], technical and social characteristics and parameters are not the cause of preventing a public return to the use of wood—it is the absence of inspiring governmental regulations. The findings of Feldhof [
273] on the lobby involved in the construction sector of Japan can be applied to the CMs’ transitions towards sustainability on a global scale. The indicated studies [
243,
244,
245,
247,
248,
249,
250] provided sufficient evidence for the effectiveness of wood on occupants’ physical health. This study has also investigated the interconnectivity of physical and psychological health.
Comparable to the findings of Alexander [
100], in objective planning, people’s preferences and feelings should be incorporated into the design (i.e., PCMs). Although the study of Hoibo et al. [
287] argues that age categories influence societal trends, the current investigation on the PCMs shows that, in the end, timber constructions are preferred by society as the most favourable CS for their desired houses. From a mental health point of view, the occupants are more satisfied with their timber CMs; they are happier and will thus have improved health and WB. Although this research concentrates on houses, the results related to the users of buildings with other functions often apply to housing but with different interpretations. Michigan’s researchers also proved that nature enhances memory and increases office workers’ productivity by more than 20%. Hence, similar to the findings of Pretty et al. [
224] and Makram [
288], which show that involving nature in people’s lives will increase their health status, the current research observed that wood, as a piece of nature, has positive effects on the health of building users. In this regard, Han [
225], Burnard et al. [
242], and Dematte et al. [
221] also demonstrate comparable results. The latter is also similar to Green’s [
270] statement regarding the effect that timber in his office has on his clients’ emotions; in the same way, Nyrud et al.’s [
289] and Bysheim et al.’s [
254] findings show that wood interiors have positive effects on the recovery of patients. Clients who buy units in Mjøstårnet also express their reasoning for their purchase: “the exposed timber construction”. Leif Atle Viken (2019), who purchased an apartment on the 15th floor hugging the CLT structural element, said that it is natural and alive. The new generation of mass timber structures are exposable to the occupants; therefore, their application as PCMs, in addition to preventing the extra work, time, and costs for the covering and finishing phases, positively affects users’ physical and mental health. The social preferences in this study are also significantly aligned with Cronhjort et al.’s [
241] results regarding the positive effect of people’s visual (and other) sensations in both physical and psychological aspects. Wood’s exposure to humans is the identical constant representation of nature inside and outside houses. However, sustainably sourced timber be supported by the market for a sustainable public application. Of the 4.372 billion buildings in the world, 2.3 billion belong to the housing sector; thus, it is an influential sector in the sustainability of construction worldwide. Concerning sustainability and the long-term availability of sources of renewable resources, many studies have been continuously carried out on agroforestry. For example, institutions and organisations such as EURAF, FAO, INESUF, TNO, BMC, etc., and researchers at universities and schools such as the University of Wageningen, California, Upsala, AgroParisTech, ETH Zurich, UMaine, Yale, etc., are working to ensure the sustainability and availability of the mentioned resources. Although other sustainable sources for building materials are also currently available (e.g., earthen cementless blocks for housing by TNO, 2020), compared with plantae-based renewable resources, they are not entirely regenerative.