A Study on Contractors' Perception of Using Wood for Construction

*Hüseyin Emre Ilgın, Markku Karjalainen, Olli-Paavo Koponen and Anu Soikkeli*

## **Abstract**

Construction work is very resource-intensive, and construction projects contain many parameters, in which the choice of building material is one of the critical decisions with numerous criteria, e.g., cost, durability, and environmental impact. Moreover, this complex process includes different parties such as contractors, architects, engineers, where contractors are the most influential decision-makers in material selection. Increasing the use of renewable materials such as wood, which is a technically, economically, and environmentally viable alternative in buildings, can make construction more sustainable. The perceptions of the contractors influence what they propose and therefore the increase in wood construction. With the increasing resource efficiency and the need to adapt to climate change in the construction industry, there is need for contractors to implement sustainable practices. In this chapter, contractors' perceptions of the use of wood in buildings were examined. The results are expected to contribute to environmental remediation by developing strategies to counter perceived barriers and providing insight into new solutions to a conservative space and expanding the use of wood to achieve a more sustainable construction industry. In addition, recommendations for future research, e.g., adhesive- and metal-fastener-free dovetail wood board elements as sustainable material alternatives were presented.

**Keywords:** engineered wood products, construction, contractors, perception, carbon footprint

## **1. Introduction**

The last two decades have witnessed a dramatic increase in environmental awareness and concern about the impacts of business activities on climate and natural resources on a global scale, and environmental degradation is often addressed as a worldwide problem [1–6]. In this sense, the building construction industry can contribute significantly to the reduction of CO2 emissions, high energy consumption, excessive waste, and the development of a more resource-efficient and sustainable building environment [7–10]. More specifically, construction activities involve the use of a wide variety of materials, such as concrete, steel, timber where the choice of these materials has significant impacts on the environment [11, 12] as in the cases of tall timber buildings such as the 25-story and 87 m high Ascent

(Milwaukee, structurally topped out) (**Figure 1**), the 22-story and 73 m high HAUT (Amsterdam, under construction) (**Figure 2**), and the 18-story and 58 m high Brock Commons Tallwood House (Vancouver, 2017) (**Figure 3**) [13].

There are several criteria to consider in the selection of building materials, including stability, durability, environmental impact, speed of assembly, cost, and availability [14, 15]. Although design professionals are often involved in this process [16], contractors have the most influence in material selection decisions and therefore play an important role in supporting sustainable development in the context of the construction industry [8, 17, 18].

With the increasing resource efficiency and the need to adapt to climate change in the construction industry, contractors need to execute sustainable practices. However, contractors' decision-making and perceptions of structural frameworks remain largely unexplored, and there are few studies on the selection of structural frameworks involving contractors' perspectives (e.g., [7, 8, 19]).

Wood is the primary building material used by mankind throughout history, a sustainable and renewable building material [20, 21]. The use of wood in construction can affect carbon balance by reducing fossil fuel consumption in manufacturing compared with alternative materials, preventing emissions from cement processing, and storing carbon in wood products and forests. Thus, increasing the use of wood in construction and other long-lasting uses will help achieve sustainable development goals, where timber is recognized as a sustainable material in all major green building rating tools, e.g., Leadership in Energy and Environmental Design (USA) and the BRE Environmental Assessment Method (UK).

Wooden buildings are characterized by a lower carbon construction concept than non-wood buildings [22–26], and timber construction represents a lower embodied energy consumption compared with steel and concrete production [7]. Wooden structures provide significant advantages in combating climate change, because wood can be used as an alternative to other materials to reduce greenhouse gas emissions, but also has unique features such as storing large amounts of carbon in the structure [27, 28]. For example, estimated environmental impact of wood use in Brock Commons Tallwood House (**Figure 3**) was calculated as 1753 metric tons of CO2 in terms of carbon stored in the wood [29]. Besides being used as a building material during the construction, wood can be reused as a raw material for other structures after the building's service life or, as a last resort, burned

**Figure 1.** *Ascent (Image courtsey of Jason Korb/Korb + Associates Architects).*

*A Study on Contractors' Perception of Using Wood for Construction DOI: http://dx.doi.org/10.5772/intechopen.103168*

**Figure 2.** *HAUT (Photo courtsey of Jannes Linders).*

**Figure 3.** *Brock Commons Tallwood House (Photo by Michael Elkan and courtsey of Acton Ostry Architects).*

instead of fossil fuels [30–32]. The use of wood has many other advantages such as esthetic value, better design adaptability, ease of construction, living comfort, and indoor quality [15, 33, 34].

A better understanding of the perspectives of key actors, such as contractors, in the selection of structural frameworks, can improve insights into concrete path dependency. Because of the CO2 effects of structural frameworks, such knowledge contributes to understanding the key factors for the development of a more sustainable built environment.

Overall, this chapter examines the perceptions of the contractors regarding the use of wood in buildings. It is believed that the results will contribute to environmental remediation by developing strategies against perceived barriers and providing insight into new solutions to a conservative space and expanding the use of wood to achieve a more sustainable construction industry.

In this chapter, wood or timber refers to engineered wood products (EWPs) [35, 36] such as CLT (a prefabricated multilayer EWP, manufactured from at least three layers of boards by gluing their surfaces together with an adhesive under pressure), laminated veneer lumber (LVL; made by bonding together thin vertical softwood veneers with their grains parallel to the longitudinal axis of the section, under heat and pressure), and glue-laminated timber (glulam) (abbreviated as GL; made by gluing together several graded timber laminations with their grains parallel to the longitudinal axis of the section).

## **2. Studies on contractors' perceptions of the use of wood for construction**

In the literature, many studies focus on the technological aspects of EWPs, their use in construction, and different building solutions [37–50]. Several studies address wood as a structural material in buildings from the perspectives of key professionals (e.g., [8, 17, 51–58]) and consumers or residents (e.g., [59–64]); while there is a very limited number of works focusing on EWPs from the contractors' perspective in the literature. They are from different countries such as Sweden, Finland, Australia focusing on the use of wood as a structural material through surveys and/or interviews.

Among the studies, Hemström et al. [8] conducted interview-based research among contract managers working in contracting companies about their role in the sociotechnical regime, the choice of structural framework, and their perceptions of different alternatives. The results showed that because of their critical position in the firm, managers greatly influence the choice of the structural framework for multifamily buildings managed by the established concrete-based sociotechnical regime. The results also indicated that, due to cognitive rule-based decision-making processes, when assessing the cost of different structural frameworks, they applied their previous experience with concrete solutions as a structural material rather than making deep cost assessments. This approach has prevented timber-framed multifamily buildings from entering common use. While strong incentives for the use of concrete have made it difficult for timber frames to become more common, initiatives promoting wood could contribute to increased awareness and perceptions of wood construction and expectations for future developments in Sweden.

Riala and lola [19] conducted a study through 18 interviews with representatives from the entire value chain to identify the barriers to the adoption of multistory timber construction in Finland, the ways that wood competes with established solutions, and the possibilities for partially integrating construction into the bioeconomy. The results showed that although barriers to its adoption still exist,

multistory timber construction can offer competitive solutions for more sustainable construction. A noteworthy finding of concern for the wood products industry was that interviewees with the most experience in multistory timber construction were more critical than those with less experience. This showed that building more wood and gaining more experience is not enough to increase the popularity of wood construction. Additionally, limited possibilities were found to relate the construction industry to bioeconomy. The best way to ensure greater use of renewable materials in multistory construction would be to focus on increasing the competitiveness of multistory timber construction. For this, it was necessary to take advantage of the strengths of the wooden structure such as lightness and prefabrication possibilities and focus on improvement.

Through the qualitative analysis of the data from 36 interviews, Wang et al. [7] examined the perceptions and insights of British construction experts (e.g., industry interest group, timber manufacturer, construction material merchant) to increase understanding of Green Building and the potential of using wood for the UK construction industry. The results confirmed the important role played by the British government in the creation, promotion, and development of Green Building and showed a positive increase in the use of wood in the UK construction industry, supporting the idea that the environmental performance of wood was the main factor in wood adoption. Experts with sound knowledge of wood as a building material were also shown to agree on wood's superior environmental properties; however, end-users who do not know about wood products often have a strong prejudice against their use. Finally, it was shown that legislation, environmental awareness, attitudes and traditions, market and competition, publicity and communication, and technology and know-how are among the main drivers promoting wood as a sustainable solution for Green Building in the UK construction industry. Additionally, most respondents rated the lack of education as one of the most prominent challenges in the current construction industry, hindering the expansion of potential applications of wood products. Following the discussion on wood providing the optimal solution for Green Building (e.g., [21, 65]), the study found a generally positive attitude toward the use of wood in the UK construction industry and found support for the idea that environmental performance is the main driver for wood adoption in the Green Building concept.

Through a survey of 74 experienced construction industry participants (e.g., architects, contractors, developers, and government officials), Xia et al. [11] explored the main barriers to the use of timber framing in multistory construction in Australia. According to the results, the barriers identified can be broadly divided into five groups: lack of legal support, lack of industry interest, lack of experienced professionals, perception of wood framing disadvantages, and limited awareness of wood framing advantages. The survey confirmed the limited awareness of the new wood technologies available, as well as the biggest barriers to the perceived increase in maintenance costs and fire risk. The results are expected to benefit the government and the timber industry by contributing to environmental remediation by developing strategies to increase the use of multistory timber technologies by countering perceived barriers in the Australian context. One approach to overcoming these barriers might be the collaboration of various stakeholders such as governments, customers, designers, and contractors. It was suggested that the government may introduce more supportive legislation and regulations to encourage the use of wood for structural purposes. Industry training (e.g., workshops and seminars) and education in timber structures might have contributed to increasing awareness and knowledge of technological innovations in wood products in the construction industry.

Tan et al. [66] extensively reviewed studies on the relationship between sustainability performance and contractors' competitiveness. The results indicated that there was no unique relationship between the two variables. Therefore, a framework for the implementation of sustainable construction practices was developed to increase competitiveness to help contractors develop their sustainability policies, strategies, and practices to meet the growing need for sustainable development in the construction industry.

Qi et al. [4] aimed to identify the factors affecting contractors' adoption of green construction practices through a survey. The results showed that managerial concern is the most important driver in the adoption of green practices. Significant relationships were also found between government regulation and enterprise size, along with the adoption of green construction practices, while there was no substantial evidence of the relationship between the adoption of green construction practices and perceived stakeholder pressures. This study aimed to contribute to better decision-making regarding the implementation of green construction practices.

## **3. Conclusions and recommendations**

This study aimed to understand the contractors' perceptions of the use of wood for construction. In doing so, this chapter attempted to identify perceived major barriers to timber utilization. However, as the focus of conducted research among contractors differed as noted above, it was not possible to compare these studies with each other, but still, some conclusions were reached as follows: (a) their previous experience with concrete solutions, especially as a structural material, could have prevented them from conducting in-depth analysis for new materials; (b) building more wood and gaining more experience may not be enough to increase the popularity of wood construction; (c) lack of legal support, lack of industry interest, lack of experienced professionals, lack of education, perception of wood framing disadvantages, and limited awareness of wood framing advantages as well as the perceived

**Figure 4.** *Adhesive- and metal fastener-free dovetail wood board element.*

#### *A Study on Contractors' Perception of Using Wood for Construction DOI: http://dx.doi.org/10.5772/intechopen.103168*

increase in maintenance costs and fire risk were cited as barriers to wood use; (d) managerial concern was among the most important drivers for the adoption of green practices related to wood use.

In this context, the following recommendations can help address identified issues among contractors by improving general attitudes toward the use of wood: (1) providing initiatives that promote wood for increasing awareness and perception of wood construction and prospects for future developments; (2) increasing competitiveness by highlighting the strengths of wooden structure such as lightness and prefabrication possibilities; (3) establishing collaboration of critical stakeholders such as governments, customers, designers, and contractors;

(4) introducing more supportive legislation and regulations at the government level to encourage the use of wood for structural purposes; (5) organizing industry training (e.g., workshops and seminars) and education in wooden structures to increase awareness and knowledge of technological innovations in wood products in the construction industry; (6) conducting more research projects (e.g., the DoMWoB project/Dovetailed Massive Wood Board Elements for Multi-Story Buildings – *see Acknowledgments and Funding*) [67] and developing more innovative and environmentalist EWPs (e.g. adhesive- and metal-fastener-free dovetail wood board elements) (**Figure 4**) [68] to demonstrate the potential of wood for use in construction.

It is believed that this chapter will help deepen the understanding of the various aspects that shape the decision-making process particularly among contractors in the use of EWPs for construction.

## **Acknowledgements**

This project has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No [101024593].

## **Funding**

This project has also received funding (60 000 EUR) from the Marjatta and Eino.

Kolli Foundation for funding the technical performance tests including fire safety, structural, moisture transfer resistance and air-tightness, and sound insulation.

*Engineered Wood Products for Construction*

## **Author details**

Hüseyin Emre Ilgın1 \*, Markku Karjalainen1 , Olli-Paavo Koponen1 and Anu Soikkeli<sup>2</sup>

1 Tampere University, Tampere, Finland

2 University of Oulu, Oulu, Finland

\*Address all correspondence to: emre.ilgin@tuni.fi

© 2022 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

*A Study on Contractors' Perception of Using Wood for Construction DOI: http://dx.doi.org/10.5772/intechopen.103168*

## **References**

[1] Tse RYC. The implementation of EMS in construction firms: Case study in Hong Kong. Journal of Environmental Assessment Policy and Management. 2001;**3**(2):177-194

[2] Tam WYV, Tam CM, Shen LY, Zeng SX, Ho CM. Environmental performance assessment: Perceptions of project managers on the relationship between operational and environmental performance indicators. Construction Management and Economics. 2006;**24**(3):287-299

[3] Shen LY, Yao H. Improving environmental performance by means of empowerment of contractors. Management of Environmental Quality. 2006;**17**(3):242-254

[4] Qi GY, Shen LY, Zeng SX, Jorge OJ. The drivers for contractors' green innovation: An industry perspective. Journal of Cleaner Production. 2010;**18**(14):1358-1365

[5] Shrinkhal R. Economics, technology, and environmental protection: A critical analysis of phytomanagement. In: Pandey VC, Bauddh K, editors. Phytomanagement of Polluted Sites, Market Opportunities in Sustainable Phytoremediation. Amsterdam: Elsevier; 2019. pp. 569-580

[6] Maurya PK, Ali SA, Ahmad A, Zhou Q, Castro JS, Khan E, et al. An introduction to environmental degradation: Causes, consequence and mitigation. In: Environmental Degradation: Causes and Remediation Strategies. Uttarakhand, India: Agro Environ Media; 2020. DOI: 10.26832/aesa-2020-edcrs-01

[7] Wang L, Toppinen A, Juslin H. Use of wood in green building: A study of expert perspectives from the UK. Journal of Cleaner Production. 2014;**65**:350-361

[8] Hemström K, Gustavsson L, Mahapatra K. The sociotechnical regime and Swedish contractor perceptions of structural frames. Construction Management and Economics. 2017;**35**(4):184-195

[9] Kong A, Kang H, He S, Li N, Wang W. Study on the Carbon Emissions in the Whole Construction Process of Prefabricated Floor Slab. Applied Sciences. 2020;**10**:2326

[10] Sijakovic M, Peric A. Sustainable architectural design: Towards climate change mitigation. Archnet-IJAR: International Journal of Architectural Research. 2021;**15**(2):385-400

[11] Xia B, O'Neill T, Zuo J, Skitmore M, Chen Q. Perceived obstacles to multistorey timber-frame construction: An Australian study. Architectural Science Review. 2014;**57**(3):169-176

[12] Khoshnava SM, Rostami R, Zin RM, Štreimikienė D, Mardani A, Ismail M. The role of green building materials in reducing environmental and human health impacts. International Journal of Environmental Research and Public Health. 2020;**17**(7):2589

[13] CTBUH. Council on Tall Buildings and Urban Habitat. Illinois Institute of Technology, S.R. Crown Hall, 3360 South State Street, Chicago, Illinois, USA. Available from: www.ctbuh.org [Accessed: February 10, 2022]

[14] Dodoo A, Gustavsson L, Sathre R. Effect of thermal mass on life cycle primary energy balances of a concreteand a wood-frame building. Applied Energy. 2012;**92**:462-472

[15] Sandak A, Sandak J, Brzezicki M, Kutnar A. Biomaterials for Building Skins. In: Bio-based Building Skin. Environmental Footprints and Ecodesign of Products and Processes.

Singapore: Springer; 2019. p. 16. DOI: 10.1007/978-981-13-3747-5\_2

[16] Bayne K, Taylor S. Attitudes to the use of Wood as a Structural Material in Non-residential Building Applications: Opportunities for Growth. PN05.1020. Forest and Wood Products Australia: Melbourne, VIC; 2006

[17] Roos A, Woxblom L, McCluskey D. The influence of architects and structural engineers on timber in construction - Perceptions and roles. Silva Fennica. 2010;**44**(5):871-884

[18] Hemström K, Mahapatra K, Gustavsson L. Perceptions, attitudes and interest of Swedish architects towards the use of wood frames in multi-storey buildings. Resources, Conservation and Recycling. 2011;**55**:1013-1021

[19] Riala M, Ilola L. Multi-storey timber construction and bioeconomy: Barriers and opportunities. Scandinavian Journal of Forest Research. 2014;**29**(4):367-377

[20] Herbert S. The oldest wood construction of the world, (Der aelteste Holzbau der Welt). Artikel aus der Zeitschrift: GWF Wasser Abwasser. 1993;**134**(12):711-714

[21] Sathre R, Gustavsson L. Using wood products to mitigate climate change: External costs and structural change. Applied Energy. 2009;**86**(2):251-257

[22] Ritter M, Skog K, Bergman R. Science Supporting the Economic and Environmental Benefits of Using Wood and Wood Products in Green Building Construction; General Technical Report FPL-GTR-206. Madison, WI, USA: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory; 2011. pp. 1-9

[23] Pierobon F, Huang M, Simonen K, Ganguly I. Environmental benefits of using hybrid CLT structure in midrise

non-residential construction: An LCA based comparative case study in the U.S. Pacific Northwest. Journal of Building Engineering. 2019;**26**:100862

[24] Dong Y, Qin T, Zhou S, Huang L, Bo R, Guo H, et al. Comparative whole building life cycle assessment of energy saving and carbon reduction performance of reinforced concrete and timber stadiums—A case study in China. Sustainability. 2020;**12**:1566

[25] Lolli N, Fufa MS, Wiik MK. An assessment of greenhouse gas emissions from CLT and glulam in two residential nearly zero energy buildings. Wood Material Science and Engineering. 2019;**14**:342-354

[26] Lukić I, Premrov M, Leskovar ŽV, Passer A. Assessment of the environmental impact of timber and its potential to mitigate embodied GHG emissions. IOP Conference Series: Earth and Environmental Science. 2020;**588**:1.01-1.05

[27] Kazulis V, Muizniece I, Zihare L, Blumberga D. Carbon storage in wood products. Energy Procedia. 2017;**128**:558-563

[28] Green MC, Karsh JE. The Case for Tall Wood Buildings—How Mass Timber Offers a Safe, Economical, and Environmentally Friendly Alternative for Tall Building Structures; Mgb ARCHITECTURE + DESIGN, Equilibrium Consulting, LMDG Ltd., Eds. Vancouver, BC, Canada: BTY Group; 2012

[29] The Canadian Wood Council – CWC. The Advent of Tall Wood Structures in Canada, a Case Study. Ontario: Brock Commons Tallwood House, University of British Columbia Vancouver Campus; 2018. Available from: https://cwc.ca/wp-content/ uploads/2019/03/CS-BrockCommon. Study\_.23.pdf Accessed: February 10, 2022

#### *A Study on Contractors' Perception of Using Wood for Construction DOI: http://dx.doi.org/10.5772/intechopen.103168*

[30] Werner F, Taverna R, Hofer P, Richter K. Carbon pool and substitution effects of an increased use of wood in buildings in Switzerland: First estimates. Annals of Forest Science. 2005;**62**:889-902

[31] Kutnar A, Hill C. Life cycle assessment—Opportunities for forest products sector. BioProducts Business. 2017;**2**:52-64

[32] Bergman RD, Falk RH, Gu H, Napier TR, Meil J. Life-Cycle Energy and GHG Emissions for New and Recovered Softwood Framing Lumber and Hardwood Flooring Considering End-of-Life Scenarios; Res. Pap. FPL-RP-672. Madison, WI, USA: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory; 2013. p. 35

[33] Gold S, Rubik F. Consumer attitudes towards timber as a construction material and towards timber frame houses – Selected findings of a representative survey among the German population. Journal of Cleaner Production. 2009;**17**(2):303-309

[34] Nolan G. Timber in Multi-Residential, Commercial and Industrial Building: Recognising Opportunities and Constraints. PNA140-0809. Melbourne, VIC: Forest and Wood Products Australia, 2011

[35] Wang Z, Yin T. Cross-Laminated Timber: A Review on Its Characteristics and an Introduction to Chinese Practices. IntechOpen: London, UK; 2021

[36] Rahman T, Ashraf M, Ghabraie K, Subhani M. Evaluating Timoshenko method for analyzing CLT under out-of-plane loading. Buildings. 2020;**10**:184

[37] Zwerger K. Recognizing the similar and thus accepting the other: The European and Japanese traditions of

building with wood. Journal of Traditional Building, Architecture and Urbanism. 2021;**2**:305-317

[38] Van Damme B, Schoenwald S, Zemp A. Modeling the bending vibration of cross-laminated timber beams. European Journal of Wood and Wood Products. 2017;**75**:985-994

[39] Chiniforush AA, Akbarnezhad A, Valipour H, Xiao J. Energy implications of using steel-timber composite (STC) elements in buildings. Energy and Buildings. 2018;**176**:203-215

[40] Toivonen R, Lähtinen K. Sustainability—A Literature Review on Concealed Opportunities for Global Market Diffusion for the Cross-Laminated Timber (CLT) in the Urbanizing Society; The Manuscript for Bioproducts Business. Curitiba, Brazil: IUFRO; 2019

[41] Yusof NM, Tahir PM, Lee SH, Khan MA, James RMS. Mechanical and physical properties of cross-laminated timber made from Acacia mangium wood as function of adhesive types. Journal of Wood Science. 2019;**65**:20

[42] Karjalainen M, Ilgın HE. A statistical study on multi-story timber residential buildings (1995-2020) in Finland. In: Proceedings of the LIVENARCH VII Livable Environments & Architecture 7th International Congress OTHER ARCHITECT/URE(S), Trabzon, Turkey; 28-30 September 2021. Vol. I. Trabzon, Turkey: KTU Printing Center; 2021. pp. 82-94

[43] Li M, Zhang S, Gong Y, Tian Z, Ren H. Gluing techniques on bond performance and mechanical properties of crosslaminated timber (CLT) made from Larix kaempferi. Polymers. 2021;**13**:733

[44] Bahrami A, Nexén O, Jonsson J. Comparing performance of crosslaminated timber and reinforced concrete walls. International Journal of Applied Mechanics and Engineering. 2021;**26**:28-43

[45] Sun Z, Chang Z, Bai Y, Gao Z. Effects of working time on properties of a soybean meal-based adhesive for engineered wood flooring. The Journal of Adhesion. 2021:1-20 (ahead-of-print)

[46] Ilgın HE, Karjalainen M, Koponen O. Review of the Current State-of-the-Art of Dovetail Massive Wood Elements. IntechOpen: London, UK; 2021

[47] Ilgın HE, Karjalainen M, Koponen O. Dovetailed massive wood board elements for multi-story buildings. In: Proceedings of the LIVENARCH VII Livable Environments & Architecture 7th International Congress OTHER ARCHITECT/ URE(S), Trabzon, Turkey; 28-30 September 2021. Vol. I. Trabzon, Turkey: KTU Printing Center; 2021. pp. 47-60

[48] Karjalainen M, Ilgın HE, Yli-Äyhö M, Soikkeli A. Complementary Building Concept: Wooden Apartment Building: The Noppa toward Zero Energy Building Approach. IntechOpen: London, UK; 2021

[49] Tulonen L, Karjalainen M, Ilgın HE. Tall Wooden Residential Buildings in Finland: What Are the Key Factors for Design and Implementation? IntechOpen: London, UK; 2021

[50] Rinne R, Ilgın HE, Karjalainen M. Comparative study on life-cycle assessment and carbon footprint of hybrid, concrete and timber apartment buildings in Finland. International Journal of Environmental Research and Public Health. 2022;**19**:774

[51] Ilgın HE, Karjalainen M. Perceptions, Attitudes, and Interest of Architects in the Use of Engineered Wood Products for Construction: A Review. IntechOpen: London, UK; 2021

[52] Karjalainen M, Ilgın HE, Tulonen L. Main design considerations and prospects of contemporary tall timber apartment buildings: Views of key professionals from Finland. Sustainability. 2021;**13**:6593

[53] Aaltonen A, Hurmekoski E, Korhonen J. What about wood?— "Nonwood" construction experts' perceptions of environmental regulation, business environment, and future trends in residential multistory building in Finland. Forest Products Journal. 2021;**71**:342-351

[54] Ilgın HE, Karjalainen M, Pelsmakers S. Finnish architects' attitudes towards multi-storey timberresidential buildings. International Journal of Building Pathology and Adaptation. 2021;ahead-of-print

[55] Markström E, Kuzman MK, Bystedt A, Sandberg D, Fredriksson M. Swedish architects view of engineered wood products in buildings. Journal of Cleaner Production. 2018;**181**:33-41

[56] Karjalainen M, Ilgın HE, Somelar D. Wooden additional floors in old apartment buildings: Perspectives of housing and real estate companies from Finland. Buildings. 2021;**11**:316

[57] Karjalainen M, Ilgın HE, Metsäranta L, Norvasuo M. Wooden Facade Renovation and Additional Floor Construction for Suburban Development in Finland. IntechOpen: London, UK; 2022

[58] Karjalainen M, Ilgın HE, Metsäranta L, Norvasuo M. Suburban residents' preferences for livable residential area in Finland. Sustainability. 2021;**13**:11841

[59] Karjalainen M, Ilgın HE, Somelar D. Wooden Extra Stories in Concrete Block of Flats in Finland as an Ecologically Sensitive Engineering Solution, Ecological Engineering—Addressing

*A Study on Contractors' Perception of Using Wood for Construction DOI: http://dx.doi.org/10.5772/intechopen.103168*

Climate Challenges and Risks. IntechOpen: London, UK; 2021

[60] Karjalainen M. The Finnish Multi-Story Timber Apartment Building as a Pioneer in the Development of Timber Construction. Oulu, Finland: University of Oulu; 2002 (In Finnish)

[61] Karjalainen M, Ilgın HE. The change over time in Finnish Residents' attitudes towards multi-story timber apartment buildings. Sustainability. 2021;**13**:5501

[62] Lähtinen K, Harju C, Toppinen A. Consumers' perceptions on the properties of wood affecting their willingness to live in and prejudices against houses made of timber. Wood Material Science and Engineering. 2019;**14**:325-331

[63] Kylkilahti E, Berghäll S, Autio M, Nurminen J, Toivonen R, Lähtinen K, et al. A consumer-driven bioeconomy in housing? Combining consumption style with students' perceptions of the use of wood in multi-story buildings. Ambio. 2020;**49**:1943-1957

[64] Karjalainen M, Ilgın HE, Metsäranta L, Norvasuo M. Residents' attitudes towards wooden facade renovation and additional floor construction in Finland. The International Journal of Environmental Research and Public Health. 2021;**18**:12316

[65] Gustavsson L, Joelsson A, Sathre R. Life cycle primary energy use and carbon emission of an eight-storey wood-framed apartment building. Energy and Buildings. 2010;**42**(2): 230-242

[66] Tan YT, Shen LY, Yao H. Sustainable construction practice and contractors' competitiveness: A preliminary study. Habitat International. 2011;**35**:225-230

[67] Ilgın HE, Karjalainen M. Preliminary design proposals for dovetail wood board elements in multi-story building construction. Architecture. 2021;**1**:56-68

[68] Ilgın HE, Karjalainen M, Koponen O. Various Geometric Configuration Proposals for Dovetail Wooden Horizontal Structural Members in Multistory Building Construction. IntechOpen: London, UK; 2022

## **Chapter 7**
