Barriers to the Use of Cross-Laminated Timber for Mid-Rise Residential Buildings in the UAE

Abstract

Buildings account for approximately 40% of global energy consumption annually, with substantial energy use occurring during both the construction and operation phases. The energy required for the production of construction materials contributes significantly to the overall energy intensity of the building sector. This underscores the critical need for materials with low embodied energy to mitigate the environmental impact associated with building construction and operation. Cross-laminated timber, massive timber product with excellent load-bearing capabilities, is becoming popular in mid-rise buildings worldwide. CLT’s environmental, economic, and social benefits surpass traditional materials, and its use is widespread in Europe, America, Canada, and Australia. However, no mid-rise CLT buildings have been constructed in the UAE yet. This study aims to investigate and identify the barriers to adopting CLT as a building material and construction system for mid-rise buildings in the UAE. A qualitative approach is used to study stakeholders’ behavior towards CLT construction. A comprehensive questionnaire survey and conversational interviews are conducted, with the responses analyzed to identify patterns and themes. The results identify the existing barriers within the construction industry impeding the adoption of cross-laminated timber (CLT). Additionally, the study discusses strategies necessary to facilitate the widespread adoption of CLT. These findings will inform future research aimed at addressing the obstacles to constructing mid-rise buildings using CLT in the UAE.

1. Introduction

Globally, temperatures have been steadily increasing over the past century, with a significant rise of 0.4–0.8 °C observed since the early 1900s, and a substantial portion of this warming occurring in the last three decades, with projections indicating a further rise of approximately 1.4 °C to exceeding 5.8 °C by the year 2100 [1]. The scientific consensus points towards human activities as the primary driver of recent warming trends, particularly through the release of greenhouse gases into the atmosphere from activities such as energy production by fossil fuel combustion and consumption [1,2,3]. The construction, operation, and utilization of buildings release a substantial amount of CO₂ into the atmosphere [4].

Energy consumption in buildings consists of operational energy, used during the operational phase of the building, and embodied energy, which includes energy from extraction, processing, manufacturing, transportation, construction, maintenance, and demolition of materials and products [5,6]. Operational energy accounts for about 80% of energy use in buildings, while embodied energy contributes around 10% to 20% [7]. Embodied energy is linked to the manufacturing of building materials, temperature regulation energy consumption, and heating and cooling systems, impacting overall energy consumption in the construction industry [8]. Embodied emissions, especially from the product stage of materials, are identified as a major carbon contributor in the life cycle of buildings, with emissions before the building use stage constituting a significant portion of the total carbon footprint of a new building [9]. The manufacturing of construction materials, extensively used in buildings, consumes energy and emits CO₂, further intensifying the environmental impact of buildings [10].

Studies emphasize the importance of evaluating the embodied carbon in buildings, as it can significantly contribute to lifetime greenhouse gas emissions. Estimates suggest that embodied carbon can constitute up to 80% of the total greenhouse gas emissions for energy-efficient buildings [11]. A study by Rauf and Shafiq [12] on an eight-story apartment building demonstrates that substituting the reinforced concrete floor with a cross-laminated timber (CLT) floor results in a more than fourfold reduction in the embodied energy associated with floor construction. In another study, the embodied carbon of a CLT frame building was found to be substantially lower than that of a reinforced concrete frame equivalent [13].

Using more carbon-efficient materials is recognized as a key strategy to reduce the carbon footprint of buildings [14]. Thus, by choosing low embodied carbon materials, the building construction sector can effectively reduce carbon emissions during both the construction and disposal stages [15,16]. A study in China revealed that a seven-story CLT building could achieve a 29.4% energy saving and a 24.6% carbon reduction compared to a concrete building during the operational stage [17]. Moreover, timber building elements, being about 50% carbon by weight, have the ability to sequester carbon over their lifespan, thus aiding in carbon storage [18]. Studies have shown that CLT can store significant amounts of CO₂, with one cubic meter of timber capable of storing up to 800 kg of CO₂ [19]. Additionally, the use of wood-based materials like CLT has been linked to reduced greenhouse gas emissions in the construction sector [20].

Thus, expanding the use of timber in construction can significantly enhance sustainable building practices [21]. CLT offers various other advantages, such as low environmental impact, high fire resistance, good thermal insulation, and ease of assembly with minimal site waste [22]. Additionally, the use of CLT in construction allows for rapid erection times, reduced labor, and smaller cranes on site. Technological advances and academic research can improve the ease of disassembly for material reuse, contributing to a resource-efficient product life cycle [23]. Moreover, research indicates that CLT panels can sustain their structural integrity for a significant duration when exposed to fire, leading to their conditional fire-resistant status based on experimental fire resistance assessments and charring rate investigations [24].

CLT also offers advantages such as lightweight design, superior bending resistance, and engineering plasticity. It offers a higher strength-to-weight ratio and is lighter than steel and concrete, leading to reduced foundation sizes, cost savings, and quicker construction [25]. In terms of specific properties, CLT exhibits excellent dimensional stability, a high strength-to-weight ratio, good fire performance, structural strength, and lateral stiffness, making it a viable replacement for concrete and steel in various applications [26,27]. Furthermore, the mechanical properties of CLT can be equal to or higher than the raw material when manufactured according to standards, with CLT panels offering high stiffness properties that heavily rely on the mechanical properties of metal connections [28,29]. CLT construction has been a subject of debate regarding its cost-effectiveness compared to traditional materials like reinforced concrete [30]. While some studies suggest that CLT can be a cost-effective alternative for building construction [31], others indicate that the material cost of CLT slabs during construction can be significantly higher than that of RC slabs, impacting overall costs [32]. According to [33], the cost of using CLT in mass timber building construction is $409 per square meter of floor area, which corresponds to 0.21 cubic meters of CLT, while traditional timber costs $2 to $8.5 per cubic meter [34]. Thus, the percentage difference between the cost of CLT and traditional timber can vary significantly. Despite the potential higher initial costs associated with CLT construction, there are indications that using CLT can lead to cost savings in the long run. For instance, buildings using CLT panels have been found to have a shortened construction period and reduced construction costs due to the lighter self-weight of CLT compared to concrete buildings [17].

Like other building materials, CLT also has some disadvantages, such as moisture control and acoustic properties. Moisture fluctuations affect mechanical properties such as screw withdrawal resistance [35], underscoring the importance of effective moisture management in CLT construction [36]. Integrating acoustic insulation, fire protection, and moisture barriers within or to the surface of CLT panels during the manufacturing stage would create significant synergies in the construction process, saving time and eliminating uncertainties [3].

The construction of CLT buildings has increased in many parts of the world, particularly in developed countries, due to numerous benefits. Figure 1 illustrates the rising number of mass timber building projects in the United States, categorized by type of timber technology. Notably, the most significant annual growth in project count has been observed in the use of Cross-Laminated Timber [37].

Current manufacturers around the world include Austria, Italy, the Czech Republic, Sweden, Norway, Finland, Japan, Canada, and Uruguay, the largest producer being Austria. The energy efficiency of using CLT by calculating the energy consumption of transportation from Austria (the largest exporter of CLT) to Dubai in UAE is shown in Figure 2.

The calculation indicates that the total CO₂ produced is 4.91 tons for 10 tons of CLT (0.49 tons of CO₂ per ton of CLT). The graphs demonstrate that transporting building materials by ship is more sustainable than by road. Therefore, shipping CLT from European countries consumes less energy than trucking other building materials from neighboring countries. In contrast, coal-based steel manufacturing emits 1.5 to 3 tons of CO₂ per ton of steel [38], assuming the steel is produced within the UAE. However, a significant portion of the steel is imported to the UAE from countries like Saudi Arabia, Oman, and Egypt. This would result in even higher CO₂ emissions and energy consumption due to additional road transportation. This data suggests that CLT is a more sustainable construction material compared to conventional steel and concrete, even if it has to be imported from European countries.

UAE 2050 Energy strategy calls for a reduction of carbon dioxide emissions by 70%, increasing clean energy use by 50%, and improving energy efficiency by 40% by the middle of the century [39]. It asserts the country’s long-term goal of transitioning from a 20th-century, carbon-based economy to a modern, 21st-century, sustainable economy [40]. This study primarily aims to support this agenda by promoting the adoption of low-embodied energy and low-embodied carbon materials in the UAE’s building sector. By investigating the use of CLT, an engineered wood product that has various sustainable, economic, and social benefits, including carbon sequestration, this study has the potential to promote the use of renewable materials, thereby supporting the country’s energy strategy [17]. The adoption of CLT contributes to economic diversification, reduced long-term dependence on oil revenues, and better control of environmental pollution, particularly carbon emissions [41].

Several studies have been conducted to explore the barriers to the use of CLT in other countries [42,43,44,45]. For example, studies investigated the energy sustainability of CLT in residential buildings in the cold regions of China, emphasizing its potential to reduce energy consumption and carbon emissions [13,17]. Similarly, highlighted the advancements in the timber construction industry, particularly in Austria and Bavaria, where CLT-based projects have set the foundation for modern technologies [46]. Despite a rapid increase in the construction of mid-rise CLT buildings in other countries such as Switzerland, Austria, Germany, Japan, North America, Australia, and other European countries, and the UAE’s commitment to sustainable and low emissions development, mid-rise CLT buildings are yet to be constructed in the UAE. This is particularly notable given the numerous benefits associated with the use of CLT in mid-rise buildings, especially in light of the prevalent presence of mid-rise residential structures in the country, making it crucial to address this gap.

Therefore, the aim of the research has been established as an investigation to identify the barriers to the use of CLT in UAE from the stakeholder perspective and to understand how the relationship between these may guide the use of CLT for mid-rise residential buildings in U.A.E. A qualitative approach, employing systematic exploratory investigation through surveys and interviews, will gather opinions and suggestions from various selected stakeholders in the construction industry, which will then be analyzed and categorized.

2. Research Design

Conducting online surveys is a valuable method for gathering insights on the use of Cross-Laminated Timber (CLT) in the UAE. This approach enables reaching a wide array of stakeholders, including industry professionals, policymakers, architects, builders, and the general public, in a time-efficient manner [47]. Online surveys provide the advantage of collecting data anonymously, encouraging respondents to provide more honest and candid feedback, especially on sensitive topics like the use of innovative materials such as CLT [48]. Studies show that surveys and interviews provide useful information on the barriers to the adoption of a material [42,44]. The survey questions are developed based on the theoretical framework formulated based on the existing body of literature. An Informal conversational interview is also conducted. Both of these help to answer the research question. The results of the survey and interview are analyzed, and the adoption strategies are discussed. Figure 3 provides a visual representation of the research design flow.

2.1. Online Survey

Conducting online surveys is an efficient way to gather insights on the use of CLT in the UAE. This approach allows for reaching a larger number of people in a limited time, facilitating data collection from a diverse range of stakeholders, including industry professionals, policymakers, architects, builders, and the general public. They also allow for anonymous responses, which can encourage more honest feedback, especially on sensitive topics like the use of innovative materials such as CLT [49,50]. An online survey was conducted using Google Forms to collect data on stakeholders’ perceptions of the barriers to the use of CLT in the UAE. The stakeholders are selected carefully as the knowledge of study participants would directly impact the quality of data collected [51]. The technical stakeholders like architects, engineers, and construction managers working in the UAE were selected because they are directly connected to the traditional construction industry and building teams. They are also aware of the materials used in the construction industry, and their perception of new materials is valuable. The opinions and perceptions of non-technical participants like policymakers, owners, or clients are also valuable for our study as they relate to housing selection, the general cost of housing, and the lack of government policies. These experiences might orient the individual’s mindset and understanding of the building material under study.

The technical stakeholders with a minimum of 1 year of working experience were selected for the survey as this would give more reliable data due to a better understanding of the UAE construction market. Certainly, targeting different sections of professionals, including students, engineers, and managers, in the survey can provide a comprehensive and diverse set of insights.

The literature study suggests several potential barriers to the adoption of CLT in UAE, such as economic, political, technological, regulations, standards, and knowledge. Additionally, numerous stakeholders are involved in the decision-making process. The questionnaire falls into 3 sections based on the nature of the information to be collected.

Section 1 gives the demographic information of the participants and their experience in the construction industry. The stakeholders’ technical background and experience help collect appropriate and reliable data.

Section 2 formulates questions that provide information on the familiarity of CLT among the stakeholders. A survey conducted among construction professionals in the United States by Laguardo and Espinoza shows that more than 50% of the stakeholders in the construction industry are not familiar with CLT [52]. This trend could likely extend to the UAE context as well, indicating the importance of incorporating questions that introduce this concept into the survey.

Section 3 contains more technical information relating to the potential barriers as derived from the literature study. These barriers have been further categorized into 5 major categories viz, Political environment, social barriers, economic barriers, technological barriers, and context-specific barriers.

A brief introduction to the survey, including an overview of Cross-Laminated Timber (CLT) and its benefits, is provided. This gives the participants a glimpse of the study prior to the questionnaire. A brief description of CLT, along with an example with the help of an image, will make it easier to convey the intention of the study and the survey itself. The interview structure included 15 questions in 3 categories, as presented in

Table 1. Survey Questions and Categories.

Section	Categories	Question
Section 1: Demographic data	Role/Position	Architect/Construction Manager/Project owner/Structural Engineer/policy maker/Educational field
	Years of experience	Less than 5 years; 5–10 years; 10–15 years; 15 years or more.
Section 2: Familiarity of CLT		Are you familiar with Cross-Laminated Timber (CLT)?
	Level of familiarity	On a scale of 1 to 5, how well do you understand the benefits of using CLT in construction?
		Have you been involved in a project that utilized CLT?
Section 3: Barriers	General	What do you perceive as the main barriers to the use of CLT in the UAE?
	Political Environment	To what extent do you believe government policies and priorities affect the adoption of CLT in the UAE?
		Have you observed any specific government policies or initiatives that support or hinder the use of CLT in the UAE? Please describe.
Section 3: Barriers	Economic barriers	How do you perceive the cost of construction using CLT compared to traditional construction methods in the UAE?
		Do you think government funding and subsidies could promote the adoption of CLT in the region?
	Social barriers	To what extent do you think public knowledge and awareness about CLT impact its adoption in the UAE?
		Is there a need for more education and training on CLT among professionals in the UAE’s construction industry?
	Context-specific barriers	Are there any specific local challenges such as lack of local suppliers or the cost of importing CLT materials that you have encountered?
	Technological barriers	How concerned are you about the fire safety properties of CLT in the UAE?
		Do you think research and testing on fire safety and other technical aspects of CLT can address these concerns over time?
		Have you encountered any issues related to moisture or acoustics when considering the use of CLT in construction projects in the UAE?
Section 4	Additional comments	Please provide any additional comments or suggestions related to the barriers to the use of CLT in the UAE that you believe are important.

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Conducting Survey

An online survey is formulated using Google Forms, and the link is shared with the selected participants through e-mail or WhatsApp to enhance accessibility, engagement, and response rates. The survey is conducted in two stages: pilot survey and main survey. A pilot survey is typically conducted as a preliminary step before the main survey to test the survey instrument, procedures, and data collection methods [53]. It allows researchers to identify and rectify any issues with the survey tool, ensuring that it aligns with the research objectives and is valid for the study [53,54]. In contrast, the main survey is the primary data collection effort aimed at gathering information from the target population to achieve the research objectives [55]. The main survey involves a larger sample size and is conducted after the pilot survey to implement any necessary adjustments identified during the pilot phase [56].

A pilot survey is conducted for a selected small group of participants to assess the suitability of the survey and refine the questionnaire. The participants selected were experienced personnel in the education industry who were familiar with the material, ensuring valuable feedback on the survey. The survey link was shared via email, along with a brief explanation of its purpose and importance, encouraging honest feedback and suggestions for improvement. The results were collected, and the findings were analyzed using real-time analysis in Google Forms to identify any issues or areas for improvement. Based on the findings from the pilot survey, necessary revisions to the questionnaire were made, including rephrasing a few questions in Section 3, adding new options, and adjusting the survey structure to enhance clarity and effectiveness.

Once the pilot survey is conducted and the questionnaire refined, the main survey is conducted. The errors in the questionnaire identified during the pilot study are corrected, and the link is sent to the selected participants via email and WhatsApp, depending on their availability and accessibility. The participants include architects, engineers, clients, researchers, policymakers, and developers, as mentioned in the previous section. A brief introduction to the survey is provided, emphasizing the importance of their input and the confidentiality of their responses. Clear instructions on how to complete the survey are given prior to filling it out to avoid any errors and ensure more reliable results.

Once the survey is completed, the responses are analyzed using Google Forms’ built-in tools to study trends, patterns, and insights. These patterns and trends are then graphically represented with the help of Microsoft Excel to convey meaningful results.

2.2. Informal Conversational Interview

An informal conversational interview is a type of interview that is conducted as a conversation with less rigid questions and aims to gather the interviewee’s insights on the topic in a more relaxed manner. This methodology was adopted to delve deeply into the participants’ experiences and perspectives [57].

The interviewee is the owner of a Portuguese CLT importing company based in Dubai, set up around 5 years back. It is important to note that no project has been completed since the beginning except for one of the pavilion buildings in Expo 2020 Dubai. This revelation prompts the authors to underscore the importance of delving into the thoughts, experiences, and hurdles encountered by these individuals in their journey to introduce CLT into the market. Understanding the journey of our interviewee, particularly their endeavors to navigate the complexities of the CLT market, could provide invaluable insights into the dynamics at play and the underlying factors influencing market penetration and project execution. By engaging in candid conversation, we could gain a nuanced understanding of the unique challenges faced, ranging from regulatory hurdles and logistical constraints to market perceptions and competitive landscapes.

By fostering an environment of open dialogue and knowledge exchange, we could gather some valuable insights into the barriers to the adoption of CLT in the current market and the future opportunities in the market. His valuable learnings from his experience were collected through a telephonic informal conversational interview. The primary objectives of the interview were to:

• Identify contextually significant CLT adoption barriers in the UAE,
• Identify if a difference occurs contextually as studied in the literature and in the real context of UAE.
• Identify the possible solutions to the barriers to the adoption of CLT in UAE from their perspective.

3. Results

This section provides a holistic view of the barriers as perceived by the study participants and aims to clarify the importance of each barrier specific to the context. By examining the dialogue and conversation, recurring themes and patterns are identified and categorized into different barrier categories.

3.1. Survey Results: Demography and Familiarity

The survey is conducted through online forms, and the results are downloaded and analyzed after completing the survey by 30 participants, all of whom have been in the building industry for more than at least 1 year.

3.1.1. Demography and Qualifications

The selected stakeholders are the people closely related to the construction industry. This includes technical and non-technical occupation participants, as mentioned earlier.

Occupation

The distribution of participants, as depicted in Figure 4, indicates a strong representation of architects and structural engineers. This aligns with the significance of their roles in the construction industry, particularly in material selection and structural design. Architects, being the primary decision-makers in building design, play a crucial role in determining the suitability of materials like CLT for construction projects. Their input can heavily influence the adoption and integration of innovative materials such as CLT into architectural designs.

Similarly, structural engineers contribute essential expertise in assessing the structural properties of materials like CLT. Their understanding of how CLT behaves under various loads and environmental conditions is crucial for ensuring the safety and stability of buildings constructed with this material. Their involvement in the survey reflects the importance of considering structural integrity in the adoption of CLT.

The subsequent participation of construction managers, professionals from the educational field, civil engineers, cost management professionals, and project owners indicates a broader interest in and engagement with the topic. Each of these professionals brings unique perspectives and concerns to the table, contributing to a more comprehensive understanding of the challenges and opportunities associated with adopting CLT as a building material. However, the absence of responses from policymakers, despite concerted efforts, is a notable gap.

Years of Experience

The distribution of participants based on their years of experience in the construction industry provides valuable insights into the demographic makeup of the survey respondents. The fact that the majority of participants fall within the 5–10 years experience range suggests a cohort of professionals who have attained a significant level of expertise and knowledge within the industry. This group is likely well-versed in the intricacies of construction practices, including material selection, project management, and regulatory compliance. Their input can offer valuable perspectives on the feasibility and practicality of adopting CLT as a building material.

The presence of a substantial number of participants with 1 to 5 years of experience is also noteworthy. While relatively newer to the industry, these individuals bring fresh perspectives and may offer insights shaped by recent advancements in construction technology and methodologies. It is noteworthy that the survey criteria included a minimum requirement of 1 year of experience in the construction industry. Additionally, the participation of a few respondents with 10–15 years of experience and above adds depth to the survey findings. Their perspectives may reflect broader trends, historical context, and nuanced considerations that can enrich the discussion on CLT adoption and its implications for the construction industry. Overall, the diverse range of experience levels among participants enhances the validity and relevance of the survey findings, ensuring that insights are reflective of the varying perspectives and expertise within the construction community.

Types of Projects Involved

The distribution of participants based on the type of projects they are involved in provides valuable insights into the applicability of CLT within different segments of the construction industry. Notably, 34.5% of participants are engaged in residential mid-rise buildings, which aligns closely with the focus of the study. CLT offers significant benefits when used in mid-rise construction due to its structural properties, sustainability, and construction efficiency [45,58,59]. Therefore, the substantial representation of professionals working on mid-rise residential projects enhances the reliability and relevance of the data collected for examining the adoption of CLT in this specific context.

3.1.2. Familiarity with CLT

Questions 4 and 5 aim to gauge participants’ familiarity with CLT and their understanding of its associated benefits. These inquiries serve as pivotal indicators of the industry’s readiness and receptiveness towards adopting it as a building material. The options provided are “very unfamiliar,” “basic knowledge,” and “very familiar” for the question on how familiar the participant is with CLT. A scale of “not at all—very well” is provided for the question on how well the participant understands the benefits of CLT, where “not at all” indicates the least knowledge of the benefits, and “very well” indicates a high level of knowledge (Figure 5).

The findings reveal a significant trend: a significant portion of respondents are either not familiar with CLT or have basic knowledge, indicating a potential knowledge gap within the industry regarding this innovative material. Moreover, the results also indicate that only a small percentage of participants demonstrate an understanding of the benefits associated with CLT. This suggests that even among those who are aware of CLT, there may be a lack of comprehensive knowledge regarding its advantages, such as its environmental sustainability, structural performance, and cost-effectiveness. This pattern underscores the importance of targeted educational initiatives and information dissemination campaigns aimed at enhancing awareness and understanding of CLT’s potential benefits among industry professionals.

3.2. Survey Results: Barrier Analysis

The responses to the questionnaires and the comments were analyzed, and a theme could be built based on the participants’ responses. These were divided into six main categories, which are: (a) knowledge and awareness, (b) Material Availability, (c) Economic barriers, (d) Political barriers, (e) Social barriers, and (f) Technological barriers. The relationship between “barriers and category” pertains to identifying and understanding the specific obstacles that fall within distinct categories relevant to a particular context. This relationship helps in organizing and addressing challenges more effectively by categorizing them based on their nature and impact.

The participants were given the options on the left column of the table, and each participant could choose more than one option. The results show that lack of knowledge and awareness is perceived as the main barrier by 18 participants, followed by economic barriers commented by 13 participants, followed by political barriers, which were mentioned by 10 participants, while material availability by 8 participants, social barriers by 6, and technological barriers by 2 as can be seen in

Table 2. Barriers as perceived by the participants.

Barriers	Category	No. of Responses
Lack of awareness and education about CLT	Knowledge and Awareness	18
High initial costs	Economic	13
Regulatory or code restrictions	Political	10
Limited availability of materials	Material availability	8
Resistance to change in traditional methods	Social	6
Durability compared to steel and concrete	Technological	2

.

Figure 6 shows the proportion of survey participants who think each of these themes is the main barrier. It shows that the number of people who think knowledge and awareness-related barriers are the highest, followed by economic, political, material availability, social, and technological barriers. The responses from participants show that lack of knowledge of the novel material is the main reason for reluctance to adopt the material. Economic reasons, which include the high initial cost compared to the traditional methods of construction, are the second highest barrier perceived by the respondents.

3.2.1. Knowledge and Awareness

The knowledge theme includes a lack of awareness, education, and understanding of mass timber, particularly CLT as a building material, that is more sustainable and carbon-friendly for a better future in the construction industry.

Questions 4 and 5, designed to understand the participant’s familiarity with the material, show that the majority of the participants opted for ‘basic knowledge’ and ‘very less’ knowledge on the benefits of CLT.

Figure 7 depicts the participants’ perceptions regarding the influence of knowledge and awareness on the adoption of CLT in the UAE, rated on a scale of 1 to 5, where 1 signifies ‘not at all’ and 5 indicates a ‘very large’ impact. The data reveals that the majority of participants believe that public knowledge and awareness have a significant impact, rating it as ‘very large’.

From the participants’ comments in the survey and from the interview, it can be seen that this barrier has three subcategories: limited knowledge, skepticism, and misinformation.

Limited Knowledge

There is limited knowledge of the material and its benefits even among the technical study participants like architects, engineers, construction managers, and educational professionals. For example, several comments provide clarification on this point. Some of the comments from the participants are listed below:

• ‘lack of awareness’,
• ‘not aware of this material’,
• ‘not sure of structural properties’,
• ‘Lack of awareness is main reason for low adoption rate across the value chain even creating dearth of suppliers locally’,
• ‘a workshop in UAEU/COE/AE about this might be interesting’,
• ‘can be used as an external door? Can it support CNC cutting etc?’,
• ‘I’m not aware enough on this topic’,
• ‘Awareness among the industry is to be increased’

These comments underscore a prevalent lack of comprehensive understanding among professionals regarding the material, indicating a strong desire to enhance their knowledge. This signifies an opportunity for further education and training initiatives to bridge the gap and equip professionals with the necessary expertise to effectively engage with the subject matter.

Misconception

Several participants highlighted the significant barrier posed by the absence of prior experience and knowledge, which can inadvertently result in the spread of misinformation. One participant commented, “I believe CLT has less durability period (high humidity and heat of the weather) compared to concrete and the life span of it is short which makes it harder to invest in”.

It is noteworthy that CLT buildings have been successfully constructed in numerous countries without evidence indicating diminished durability or lifespan compared to traditional RC buildings [60]. Another participant commented, “It should be Fire resistant and waterproof”.

Despite empirical evidence showcasing its fire-resistant properties, the stigma associated with wood materials can hinder broader acceptance and understanding of CLT’s safety and durability characteristics. Another person commented, “This region has to wait a bit more to see how the material is used somewhere else to be convinced of its opportunity”.

It is noteworthy that by 2022, countries in five continents have demonstrated interest in mass timber construction, with buildings constructed using CLT panels [61].

These comments from experienced technical professionals in the industry show that it is simply related to a lack of knowledge or outdated misconceptions about timber buildings. To address this, a comprehensive dissemination effort is crucial to promote understanding and acceptance of CLT buildings. This effort should focus on educating industry stakeholders about the structural integrity, fire resistance, and environmental benefits of CLT. By showcasing successful CLT projects through case studies and tours, stakeholders can see the practical applications and advantages firsthand. Collaboration with architects, engineers, builders, and policymakers will foster a deeper understanding of CLT technology. Additionally, disseminating research findings and performance data can counter outdated misconceptions while utilizing various media channels to ensure the information reaches a broad audience. Such a multifaceted approach will bridge the knowledge gap and encourage the adoption of CLT buildings in the construction industry.

3.2.2. Economic Barriers

The next barrier after awareness and knowledge perceived by most of the participants is the cost of material or economic barriers. A total of 23% of the participants think that CLT is not adopted in the UAE because of economic reasons.

One of the participants commented that the barrier to the adoption of CLT in UAE is that “it’s not common to be used in the market, hence the high cost and lack of suppliers”.

Another participant mentioned that “the economics involved for CLT is higher compared to the current used alternatives.” The logic of these participants’ views is, however, debatable as the initial cost of installation of CLT is currently 18 to 20% higher compared to conventional building materials like cement, block, and steel, as mentioned by the interviewee (Section 3.3). However, the studies by [17] suggest that the cost of tall CLT buildings is comparable to or even less expensive than concrete and steel options in a full life-span of building in certain regions because of savings during the maintenance, renovations, and adaptations [17].

Figure 8 shows that 43.3% of participants think that the cost of CLT construction is higher than that of traditional construction methods. However, 50% are uncertain about it, and a very small proportion think that the costs of CLT construction are lower than those of traditional methods.

Some of the other comments of the participants are, “…local supply will be a huge factor” and “I believe CLT is a product that needs to be carefully studied if it needs to be adopted here. The high initial cost and source of availability in addition to adoption of region codes is a major factor”. These comments underscore participants’ belief that local accessibility will significantly enhance the adoption of CLT. Furthermore, they emphasize the importance of ongoing research and development in this area to facilitate local production and tailor studies to the specific context, as will be discussed further in the ‘technological barriers’ section.

3.2.3. Political Barriers

A good proportion (18%) of the survey participants think that political factors cause a barrier to the adoption of CLT in the country. This major barrier can be further divided into subcategories: lack of building codes, approval from the Municipality, and lack of government initiatives.

As commented by one of the participants,

“UAE as a country is keen to adopt new technology. The regulatory body is the key area to address for any shift in technology”, which shows that it is important that the government take the lead in promoting the adoption of environmentally friendly materials for building construction within the country.

Lack of Building Codes

The building codes used in the UAE lack information on timber construction. This restricts the architects from designing CLT buildings as the UAE government does not encourage the use of international codes, unlike some other countries.

Approval from Municipality

The situation cannot be better explained than this participant whose words go like this, “We are not ready to take the risk as if getting the approval from government is delayed, we are wasting the time of the client.” This current stance of the government reflects a reluctance to go beyond existing regulations when it comes to obtaining approvals for new constructions from the municipality and civil defense. This often discourages authorities from taking proactive steps to encourage the use of environmentally friendly materials.

Lack of Government Initiatives

Government support in various forms, including financial and regulatory processes, can promote the use of CLT in the UAE.

3.2.4. Material Availability

14% of the participants perceived the lack of material availability in the region as the barrier to the adoption of CLT. The concern about material availability in the region can be understood from many comments in the survey, like “lack of local suppliers,” “local supply will be a huge factor,” and “not local material”.

Participants also perceive that the high cost of the material is due to the lack of material availability. These comments of the participants prove it, “It’s not common to be used in the market, hence the high cost and lack of suppliers,” and “The high initial cost and source of availability…….”.

The participants also perceived that producing CLT locally would make it easily adaptable in the market. One of them commented, “Research and development considering the availability of raw materials in UAE and….”.

As the region has a desert climate, wood construction is not generally used. However, it is crucial to dispel the misconception that most of the building materials used in the region are imported from other countries.

Cross-laminated timber was initially created in Europe and spread across the world from that continent. This fact justifies a more intense development of the CLT industry in the European region [62]. Thus, the main importers of CLT in UAE will be European countries. The environmental cost of transportation of CLT from one of the producer locations in Europe to the UAE has been calculated and compared with steel construction in Section 1.

3.2.5. Social Barriers

At least a small proportion (10%) of people think that social reasons act as a barrier to the adoption of CLT. The responses from the participants can be grouped into two subcategories: social acceptance and technical expertise in wood construction in the region. These aspects can be studied in detail.

• Social acceptance

In any community, there’s a natural tendency towards hesitancy when it comes to embracing new concepts or methodologies. This sentiment also holds true in the context of the UAE, where the adoption of CLT faces barriers akin to those encountered by any innovative approach. Analogous to how buildings constructed with CLT technology may not yet be prevalent in the UAE, residents and property owners exhibit reluctance towards taking the risk associated with unfamiliar construction methods.

• Technical expertise

Considering that timber construction is relatively new to this region, the scarcity of individuals with expertise in this construction method poses a significant challenge. This lack of expertise also fosters hesitancy among people to adopt this innovative material. The construction industry in the UAE heavily relies on non-citizen workers, from architects to demolition workers, all on temporary work visas [58]. Without a pool of skilled practitioners to guide the construction, there is reluctance among the stakeholders to transition to this construction method, which raises concerns about the reliability, safety, and long-term durability of buildings.

However, CLT panels are designed to be easily assembled on-site, allowing for the swift construction of multi-story buildings. This ease of assembly not only improves construction efficiency but also reduces costs and project delivery times [63]. CLT panels can be fabricated at various lengths, widths, and thicknesses, providing flexibility in design and construction [64]. The ease of bonding CLT floors with pillars, walls, or beams in the field is also improved, further enhancing the construction process [65]. Investing in training programs, workshops, and knowledge-sharing platforms can bridge this gap and build confidence among the stakeholders.

3.2.6. Technological Barriers

A very small proportion of participants (5%) think that technological barriers exist to the adoption of CLT. There are concerns among people about the fire safety of the material and other technical aspects like moisture and acoustics.

Figure 9 shows that 33.33% of the stakeholders are concerned about the fire safety properties of the material. However, it is important to note that 26.6% of the stakeholders are either not concerned or very less concerned about the fire safety of CLT. This is also related to the lack of knowledge of the technical aspects of CLT.

More research and development relevant to the context are required regarding the technical aspects of CLT, as this will help to impose regulations based on the hot desert climate. Participants also commented regarding this aspect, “Research and development considering the availability of raw materials in UAE.”

Figure 10 shows that the majority (63.3%) of participants perceive that research and development on fire safety and other technical aspects of CLT will improve the present condition and lead to more acceptance of the material in the UAE construction industry.

Figure 11 represents the categories and subcategories of barriers as analyzed from the survey results. The different opinions of the participants and their comments were studied and grouped under six major categories, namely, knowledge and awareness, economic barriers, material availability, political barriers, social barriers, and technological barriers.

3.3. Informal Conversational Interview Results

The telephonic interview conducted with the CEO of a CLT supplier company based in Dubai gave very useful insights into the study. This interview holds a very important position in this research as many practical situations that are context-specific could be identified. The company started around 4 years ago in Dubai and is still facing many problems in starting the business fully. The Oman pavilion in Expo 2020 was constructed by them using CLT, which included load-bearing and non-bearing structural elements. They say that they faced four main limitations or barriers to the use of cross-laminated timber in the region, which will be explained in the coming sections (Figure 12).

3.3.1. Municipality Approvals

As mentioned in the previous sections, approvals from the government are an important political barrier. This is mainly because there are no building codes for timber construction presently in the country’s building codes. However, many countries follow the International Building Codes (IBC) when there is an absence of any specific codes and regulations in the local building code. The problem arises because there are no regulations for hot, dry climates in the IBC. He adds that “IBC, European codes and Australian codes have been updated to adopt CLT, while in UAE, the process is happening very slow.”

He mentions that the Building systems in Dubai encourage the construction of CLT buildings. However, the building codes have not been updated in terms of the regulations for CLT construction.

3.3.2. Civil Defense Approvals

The building codes have to be updated by the municipality in partnership with the civil defense. However, the authorities are not willing to make any changes so far or initiate the required moves to incorporate these changes, as evidenced by the interviewee’s comments that “the Dubai civil defense is not a dynamic department when bringing new materials.” It should be noted that there is also a factor of lack of knowledge and lack of awareness about the sustainable benefits of the CLT at the policy-making level that is hindering this development.

3.3.3. Cultural Acceptance

The third biggest barrier, according to him, is the cultural acceptance of the material. The country is so used to construction using steel, concrete, and blocks that transitioning to a new material will not be an easy task. He gives an example, “If there are two exactly same buildings for sale constructed by one of the leading developers in the country, one made of CLT and other made of conventional materials, people will choose to pay for the latter because that is what they are familiar with…”.

There is also a lot of skepticism, as mentioned in the previous section, around this matter. He says that the biggest concern while approaching developers for construction buildings using CLT has been, “How do we say that the building is made of wood?”.

3.3.4. Cost of Construction

Another small barrier to the adoption of CLT is its cost in the current industry. Due to the added charges of transportation and technical expertise that need to be additionally provided, the cost of CLT construction is 18–20% higher than the conventional construction using steel and cement. This is also a barrier to the easy adoption of the material in the market. The interviewee also mentions several measures that can be taken to change the present situation and adopt CLT in the country, which is explained in the next section.

The results of the survey and interview demonstrate that the aim of the research has been established by identifying the barriers to the use of CLT in UAE from the stakeholder perspective, and the next section discusses how the relationship between these and the strategies that may guide to the use of CLT for mid-rise residential buildings in UAE.

4. Discussion

The aim of the research is addressed through a qualitative analysis involving survey questionnaires and an informal conversational interview with stakeholders in the construction industry, spanning different areas of expertise. The data collected is meticulously analyzed and categorized to identify the various barriers hindering the adoption of CLT in the country.

The findings from this methodology provide valuable insights into the potential adoption of CLT. The analysis reveals not only the obstacles but also the drivers that could facilitate the material’s acceptance and integration into the construction sector. These drivers are explored in detail in the subsequent section, offering a comprehensive understanding of how CLT can be effectively introduced and embraced within the industry.

As highlighted in the previous section, the major barriers to CLT adoption include a lack of knowledge and awareness among the public, as well as economic, social, technological, and material availability issues, in addition to political barriers.

By systematically improving these barriers, the construction industry can transition towards more sustainable practices, making CLT a prominent material choice. The subsequent section will delve into these strategies in greater detail, outlining a comprehensive roadmap for CLT adoption.

4.1. Barriers and Strategies

4.1.1. Knowledge and Awareness

From Figure 13, it can be seen the majority of people think that lack of knowledge and awareness of the benefits of CLT is the main barrier to the wide acceptance of this material in the country. The majority of the people who participated in the survey strongly agree that training and education on CLT among professionals can have a great impact on the adoption of the material.

To overcome the knowledge and awareness gap, educational campaigns and training programs targeting architects, builders, and the general public can be implemented. These initiatives would emphasize the benefits and practical applications of CLT, thereby fostering greater acceptance and demand, which is explained in the coming sections. Different strategies, as outlined below, can increase awareness among the public and educate them about the benefits of the material.

Workshops and Conferences

Strategies such as professional development workshops, informational seminars, industry partnerships, and collaborative research initiatives can play a crucial role in enhancing awareness, disseminating knowledge, and fostering a deeper understanding of CLT and its benefits within the construction community.

In the UAE, numerous educational workshops, conferences, and seminars are already being organized to advance the country’s sustainability goals and raise awareness among students and professionals, such as COP28, which was held in Dubai in December 2023. These existing platforms provide excellent opportunities to introduce CLT as a sustainable construction material. By incorporating sessions specifically focused on CLT into these events, participants can gain valuable insights into its advantages, applications, and long-term benefits. International platforms like COP28, which attract a global audience, offer an unparalleled opportunity to raise awareness about CLT on a broader scale. Utilizing such high-profile events to showcase CLT can help position it as a key component of sustainable construction practices worldwide. Presentations, exhibitions, and discussions at these conferences can highlight successful case studies, technological advancements, and collaborative projects involving CLT, thereby demonstrating its viability and benefits to an international audience.

Additionally, partnering with leading universities and research institutions can facilitate collaborative research initiatives that further explore and validate the benefits of CLT. Joint research projects can focus on areas such as improving the manufacturing processes, enhancing material properties, and optimizing the supply chain for CLT. The findings from these studies can be disseminated through academic journals, industry reports, and public forums, contributing to a more comprehensive understanding and acceptance of CLT.

By leveraging these strategies, the construction industry can significantly increase its adoption of CLT, driving forward the sustainability agenda and reducing the environmental impact of building practices.

Public Buildings and Infrastructure

Another important strategy for familiarizing the public with CLT is constructing public buildings and infrastructure using this material. As mentioned by the interviewee, even something as simple as a bus stop made from CLT can offer numerous benefits. Currently, bus stops in the country are made up of steel and glass, and they require constant air conditioning to maintain thermal comfort as these structures absorb and retain the summer heat, leading to higher energy consumption. Replacing steel and glass bus stops with Cross-Laminated Timber (CLT) panels reduces heat absorption, minimizing the need for air conditioning and lowering energy consumption. CLT’s insulating properties maintain comfort naturally, while its aesthetic appeal enhances the streetscape. However, more research is required on the material properties specific to the climatic conditions of the region.

By showcasing the practical applications and benefits of CLT in everyday public infrastructure, the material can gain greater visibility and acceptance among the general public. This approach not only highlights the environmental and energy-saving advantages of CLT but also demonstrates its potential to enhance urban design and public spaces.

Skepticism

Skepticism, defined as the attitude of doubting knowledge claims set forth in various areas, is prevalent among people regarding the adoption of CLT. This skepticism stems from several reasons, the main reason being a lack of familiarity with CLT as a construction material, particularly in a region like the UAE where traditional materials like steel and concrete dominate. This unfamiliarity breeds uncertainty about the material’s performance, durability, and reliability. Moreover, the hot and arid climate of UAE, economic factors such as higher initial costs and higher insurance premiums for CLT buildings, and political, technological, and logistical challenges add to the skepticism. Addressing these concerns through targeted education, demonstration projects, and policy adjustments will be crucial in overcoming skepticism and fostering wider acceptance of CLT.

4.1.2. Economic Factors

As shown in Section 3, a good percentage of people think that economic reasons are the barriers to the adoption of CLT in the country. Currently, the initial costs associated with importing and integrating CLT can be perceived as high compared to traditional materials despite potential long-term savings. An increased number of suppliers in the market, more CLT projects, and greater availability of skilled labor can significantly reduce the initial construction costs compared to traditional methods. As the material gains wider acceptance, economies of scale will come into play, leading to lower transportation, labor, and material costs. Consequently, these reductions will collectively drive down the overall construction costs.

Insurance costs for CLT buildings may initially be higher due to several factors. Firstly, CLT is a relatively new material in the construction industry, and insurers may perceive it as a higher risk compared to more traditional materials such as steel and concrete. This perception can be attributed to uncertainties about CLT’s long-term durability, performance in extreme weather conditions, and fire resistance despite evidence supporting its safety and robustness. However, as CLT becomes more common and its performance is better understood through research and real-world applications, insurance costs are likely to decrease. Demonstrating the material’s fire resistance, structural integrity, and environmental benefits through pilot projects and empirical data can help insurers feel more confident in offering competitive rates for CLT buildings.

4.1.3. Political Factors

In a country like the UAE, where government policies significantly influence development and foster innovative projects, proactive government interference is necessary to promote the construction of CLT buildings. The UAE’s strategic vision for sustainable and smart urban development can greatly benefit from the adoption of CLT. The government should consider several initiatives to catalyze this process.

Subsidies, Financial Incentives and Partnerships

Government initiatives like subsidies, tax breaks, or low-interest loans can make CLT construction more economically attractive by reducing the initial costs. The government can encourage both the private and public sectors to explore and invest in CLT technology by reducing the financial barrier.

Fostering partnerships between the government, private sector, and international bodies can accelerate the adoption of CLT. Public-private partnerships (PPPs) can also facilitate large-scale CLT projects, combining public oversight with private sector efficiency and innovation.

An essential strategy to facilitate the adoption of CLT in the current landscape is to incentivize its use through government funding or subsidies. This approach aligns with the government’s sustainability objectives, as CLT is recognized as a low-carbon material that accelerates progress toward environmental goals. As depicted in Figure 14, a significant majority (80%) of participants support the notion that government funding or other forms of subsidies would effectively promote the adoption of CLT in the UAE.

Public Building Projects

The construction of public buildings using CLT, such as government offices, social housing, hospitals, and schools, can set an example for the public. These projects can showcase their benefits, including faster construction times, reduced environmental impact, and enhanced indoor environment quality. Successful public building projects can serve as case studies and benchmarks for the private sector, demonstrating the viability and advantages of CLT and increasing confidence in the private sector.

Regulatory Framework and Standards

As mentioned by the interviewee, government permits are one of the biggest hurdles faced practically during the construction of CLT buildings. The government needs to support the establishment of a regulatory framework that includes building codes and standards specifically for CLT construction. The current design practice in the UAE regarding structural timber predominantly follows Eurocode 5 (EC5) standards. Eurocode 5 provides guidelines for various aspects of timber structures, including load-bearing capacity estimation based on the effective section, and the char layer’s load resistance is close to zero [66]. Similar to the modifications made to the building codes in many European countries, Canada, and Australia, the UAE needs to update its building codes to accommodate the requirements for timber construction and fire safety for CLT buildings specific to the contextual climate. This regulatory support can also include streamlined permitting processes for CLT projects, reducing administrative hurdles, and expediting construction timelines.

Environmental Policies and Goals

Aligning CLT construction with the UAE’s broader environmental policies and sustainability goals can reinforce the importance of adopting green building practices. Highlighting the role of CLT in achieving these goals can garner support from various stakeholders and the public.

Research and Development Support

The government investments in the research and development initiatives on CLT can enhance the understanding of the material in the local context. Funding for research for universities and research institutions can lead to innovations in CLT technology tailored to the specific climate and conditions of the UAE. Research can also focus on optimizing CLT production processes to make them locally available.

4.1.4. Material Availability

The current situation involves transporting CLT from production factories in European countries to the UAE. Emerging technologies such as hybrid trucks and eco-friendly ships offer substantial potential to reduce the environmental impact of transportation by lowering emissions and improving fuel efficiency. By utilizing renewable resources for CLT production in their respective countries and minimizing environmental costs associated with transport, CLT can become more widely accepted in the UAE, resulting in easier access to this material locally. Additionally, advancements in research and development within the country can significantly boost CLT utilization, leading to the exploration of new markets.

4.1.5. Social Factors

Education and awareness campaigns are essential to overcome skepticism and build cultural acceptance. These initiatives highlight the environmental benefits, structural reliability, and aesthetic appeal of CLT and will help familiarize the common people with the material. Building a network of early adopters and showcasing successful CLT projects can create a ripple effect, encouraging wider acceptance. Publicizing these success stories can help normalize the use of CLT in mainstream construction practices.

4.1.6. Technological Factors

Intensive research and development are crucial to exploring the practical applications of the material in the UAE. This research should focus on structural performance, fire resistance, and long-term durability, all of which are specific to the local conditions. Publishing these research findings in accessible formats can help reassure developers and the public of CLT’s suitability. These publications can include detailed reports, case studies, infographics, and online resources that are easy to understand and disseminate widely. Moreover, government authorities, such as the building permits section and civil defense, should actively collaborate with research institutions and industry experts to update the existing building regulations and align them with CLT construction.

4.2. Recommendations

The lack of knowledge and awareness is a primary barrier to the adoption of Cross-Laminated Timber (CLT) in the UAE, as highlighted by survey respondents. Educational campaigns, training programs, workshops, conferences, and public infrastructure projects can address this gap by emphasizing CLT’s benefits and applications. Overcoming skepticism requires targeted education and policy adjustments. Economic factors, such as initial costs and insurance premiums, can be mitigated by increasing suppliers and government incentives. Political support through subsidies, regulatory frameworks, and public projects can drive CLT adoption. Additionally, promoting local production and technological research will enhance material availability and acceptance. Education and awareness campaigns are vital for building cultural acceptance and overcoming skepticism.

4.3. Limitations

As with any survey, there are many limitations that could arise [52]. The most important are listed below:

• Response Accuracy: Participants might not have a thorough understanding of CLT or its benefits and challenges, leading to inaccurate or uninformed responses
• Non-Response Bias: Individuals who choose not to participate in the survey or interview might have different views from those who do, potentially leading to non-response bias.
• Low response rate: Due to our low number of participants, it is also difficult to make generalizations to the entire population of interest.
• Lack of participants from political backgrounds: Despite our efforts, the study lacks input from stakeholders in the political field, which limits the comprehensiveness of the information gathered.

5. Conclusions

This study has focused on identifying the barriers to the use of CLT in the UAE for mid-rise residential buildings. CLT is a material with sustainable, economic, and social benefits that can help to reduce the greenhouse gas (GHG) emissions associated with the building sector and potentially mitigate climate change impacts. Despite its widespread utilization in numerous global contexts, including widespread applications in mid-rise buildings, CLT has yet to gain significant traction within the UAE’s construction landscape despite the country’s overarching sustainability aspirations.

The research findings, derived from surveys and interviews, underscore a number of barriers to CLT integration in the UAE. Foremost among these barriers is the lack of knowledge and awareness regarding CLT’s benefits and applications. Economic factors also pose substantial hurdles, alongside political considerations, material availability challenges, social dynamics, and technological complexities. Strategies to overcome these barriers have been discussed, encompassing educational programs to raise awareness, updating regulations and codes, offering government incentives for CLT utilization, initiatives to improve material availability, conducting research on its suitability in local conditions, and promoting the resulting outcomes.

6. Future Research

Building upon the insights gleaned from this study, future research should focus on conducting a comprehensive economic analysis to assess the cost-effectiveness of CLT compared to traditional construction materials in the UAE’s economic context. It is also crucial to investigate the impact of policy frameworks and regulations on incentivizing CLT adoption. Additionally, exploring material sourcing, supply chain management strategies, technological innovations, environmental impact assessments, and stakeholder engagement is essential for promoting CLT’s integration in mid-rise residential buildings and advancing sustainable construction practices in the UAE.