Abstract A wide variety of wood products exist for both structural and non-structural uses; however, these products are underutilized in non-residential construction in the US. Since architects are one of the key decision makers for material selection in the construction sector, we investigated architects’ familiarity, use, and perceptions of wood products. We targeted American Institute of Architects certified architects on the US West Coast, a prominent area for the forest product industry, for our survey. Respondent familiarity with wood products and their specification of wood products showed a positive relationship. Durability, fire resistance, and strength were seen as weaknesses of wood products, a common theme from the last two decades of research on this topic. Despite any weaknesses, respondents from Washington and Oregon predict the use of wood in the construction industry to grow more in the next five years compared to steel and concrete. The tools architects value most for gathering information about building materials have evolved, with an increased use of digital media and internet. Moreover, collaboration with engineers, the other key technical specifiers, has been found to be relevant to increase knowledge as well as the use of wood in construction. The authors recommend that the forest products industry improves its internet presence, reaching professionals across disciplines (i.e., engineers and architects) to increase the use of wood as a construction material for the structure and building enclosure in non-residential buildings. Keywords: architect perceptions, engineered wood products, wood construction industry Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the United States West Coast 1 Masters Student, Department of Wood Science and Engineering, College of Forestry, Oregon State University, 119 Richardson Hall, Corvallis, OR 97331. 2 Assistant Professor of Wood Design and Architecture, Department of Wood Science and Engineering, College of Forestry, Oregon State University, 236 Richardson Hall, Corvallis, OR 97331. 3 Associate Professor of Forest Products Marketing, Department of Wood Science and Engineering, College of Forestry, Oregon State University, 118 Richardson Hall, Corvallis, OR 97331. Kendall Conroy1, Mariapaola Riggio2*, and Chris Knowles3 * Corresponding author email: mariapaola.riggio@oregonstate.edu. BioProducts Business 3(10), 2018, pp. 118-135. ISSN 2378-1394. https://doi.org/10.22382/bpb-2018-010 1. Introduction Wood products represent approximately 80% - 90% of residential construction in the US (Sinha et al. 2013). While utilization of wood products in low-rise residential construction is high, the utilization of wood products in non-residential buildings is much lower (Gaston 2014; Kozak & Cohen 1999; O’Connor et al. 2004), making up roughly 10% market share, with steel accounting for 60%, and concrete 30% (Robichaud et al. 2009; Softwood Lumber Council 2010). Large potential exists to increase the amount of wood used in non-residential construction (Adair et al. 2013; Gaston et al. 2001). The 10% market share of wood products in non-residential construction is equal to about 1.5 billion board feet. It is estimated that by replacing applicable construction materials with wood products in non-residential buildings, there is po- tential for an increase to 15 billion board feet (Roth 2015). Architects and structural engineers are the two primary technical actors involved in the material selection for a given project. When specifying, architects generally consider visual and functional aspects, while engineers evaluate the structural performance of a material (Gaston et al. 2001;Kozak and Cohen 1997 and 1999; Laguarda Mallo & Espinoza 2015; O’Connor et al. 2003; O’Connor et al. 2004; Roos et al., 2010). The perceptions and knowledge architects possess regarding building materials and their performance can differ, which results in different material specifications in building design. Architects’ familiarity with wood prod- ucts available for the structure and building envelope 119 BioProducts Business 3(10) 2018 and how they perceive wood as a building material is therefore highly relevant for the wood products indus- try (e.g., manufacturers), in order to formulate effective communication and promotional strategies. A wide variety of wood products are available in North America and in other regions for both structural and nonstructural uses (e.g., Mayo, 2015). Innovations in engineered wood products in particular allow for a wider range of design possibilities than in traditional uses of wood such as low-rise housing. With new products, such as cross-laminated timber (CLT), being introduced to North America, mid- and high -rise wood structures are being built (e.g., 8-story Carbon 12 building in Portland, Oregon, completed in 2017; 5-story First Tech Credit Union Headquarters in Hillsboro, Oregon, completed in 2018, 4-story Albina Yard building in Portland, Oregon, completed in 2016). Because of new products and build- ing techniques, there has been an increase in interest among designers to incorporate wood products in con- struction (Hemström, 2010; Kitek Kuzman & Sandberg, 2017; Knowles et al., 2011). In order for architects to specify wood products, they need to be knowledge- able and familiar with the products available to them. Moreover, if they have a positive perception of these products, it is more likely that they will specify them in their projects. This research builds upon past studies, and provides current familiarity, use, and perceptions of wood prod- ucts, among architects on the US West Coast. This region is a prominent location for forest product manufactur- ers. Approximately half of Washington and Oregon are forestland (WFPA, 2017; OFRI, 2017), and approximately one third of California is forestland (USDA, 2016). Kozak & Cohen (1999) recommended investigation of architect perceptions of wood products in the Western US, since this region shows the highest market share of wood as a structural material in North America (including resi- dential and non-residential construction). Information obtained in this study can support development of communication methods, product information, and educational materials for today’s architects, with the aim of increasing the specification of wood products in non-residential construction, as well as maintaining the specification of wood use in residential construction. Since perceptions can evolve rapidly, together with advances in the industry and marketing efforts, this research aims to fill a temporal knowledge gap from previous studies (e.g., Knowles et al. 2011; Kozak & Cohen, 1999; Robichaud et al. 2009), providing the most recent data on perceptions of different types of wood-based building materials, among an important category of material specifiers (architects) and in a specific geo- graphic area, particularly relevant for the production and diffusion of engineered wood products. 2. Research objectives 1. Provide an update on the current state of US West Coast architects’ familiarity, use, and perceptions of wood products. 2. Identify what US West Coast architects currently perceive as the most prominent advantages and disadvantages of using wood products. 3. Identify how US West Coast architects prefer to gather information about materials and what ad- ditional information they need to incorporate wood into their designs. 4. Identify approaches for the wood products industry to deliver information and address identified knowl- edge needs of these architects. 3. Literature review 3.1 Advantages and barriers to wood product use Reported advantages of wood products by architects in past studies have included: aesthetics, ease of use, familiarity, and costs (Kozak & Cohen, 1999; O’Connor et al., 2004). Additionally, an array of barriers to wood prod- ucts, reported by architects in past studies, have included fire resistance, strength, durability, cost, acoustics, and building codes (Bayne & Taylor, 2006; Knowles et al., 2011; Kozak & Cohen, 1999; O’Connor et al., 2003; O’Connor et al., 2004; Roos et al., 2010). Research suggests that there are perceived weaknesses to designing with wood and that these weaknesses need to be addressed. Poor acoustic insulation of wood is one of the weaknesses re- ported (Asdrubali et al., 2016).Various design challenges for high-rise wooden buildings, such as fire, wind, seismic performance and durability, are highlighted by Buchanan (2016). However, research also suggests some of these barriers may have already been addressed. For example, predictable fire performance of large timber members is reported in many studies (e.g., Karacabeyli and Douglas, 2013). Wood construction can provide cost savings due Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 120 to wood products being relatively light weight compared to other construction materials, reducing foundation costs (Wood-WORKS! – Program of the Canadian Wood Council, 2018a). Cost savings from reduced construction time can also be achieved with prefabricated wood as- semblies (Wood-Works! – Program of the Canadian Wood Council, 2018b). Research has also suggested that when correctly designed and built, wood structural systems are capable of matching or exceeding the lifespans of comparative materials (e.g., concrete), but that buildings in North America are commonly demolished for reasons other than durability (O’Connor, 2004). Finally, a study published in 1999, found that existing building codes would have permitted the use of wood construction in over 50% of all non-residential buildings, but it was actually used in only about 17% of non-residential build- ings (Goetz & McKeever, 1999). Since then, the National Design Standard (NDS) for wood construction was up- dated in 2015 incorporating CLT, as was the International Building Code (IBC), allowing for increased height and floor areas of wood construction (Showalter et al., 2015). While wood products and wood construction systems have developed to provide increased performance and overcome some of the limitations of this material, facts on these innovations and advances do not necessary reach the architecture community (Williamson et al. 2009). In marketing, perceptions establish three of the four major stages of information processing (i.e., expo- sure, attention, interpretation) and precede information retention (Hawkins et al. 2007). Consumer choice is commonly determined by perceptions over reality, i.e., actual advantages and limitations of a given product. Therefore is it important to address the perceptions architects currently hold of wood products, so that they can reflect the actual performance and opportunities offered by these products. 3.2 Communication Communication and education are key methods for increasing awareness of new products, which is critical for the adoption and diffusion of products (King, 1996). Communication can go one-way (i.e. from the sender to receiver), or two-way (i.e. back and forth from sender to receiver), but one-way is considered less effective due to the lack of discourse (Morsing et al., 2006). Examples of one-way communication could include articles, adver- tisements, and certification labels; examples of two-way communication could include web-based services, and education (Lähtinen et al., 2017). Historically, the forest products industry has mainly been production-oriented, rather than stakeholder-oriented (Juslin & Hansen, 2002), but the industry has been changing this approach to be more stakeholder focused. A component of building relationships with stakeholders is two-way communica- tion (Lähtinen et al., 2017). 3.3 Perceptions of wood products Previous studies on the perceptions of wood products have explored a variety of topics, including perceptions of wood product use in North America (Kozak and Cohen 1997; Kozak and Cohen 1999; O’Connor et. al. 2004; Robichaud et al., 2009); perceptions of wood product use in green building (Knowles et al. 2011); perceptions of wood use in tall buildings (Hammon, 2016; Hemström, 2010; Larasatie et al., 2018) and architect perceptions of CLT (Laguarda Mallo & Espinoza 2015). The studies most relevant to the current research (Kozak and Cohen 1999; O’Connor et. al. 2004; Robichaud et al., 2009) focused on opportunities and barriers of wood-use in non-residential construction and concluded that the wood products industry is not properly addressing specifier percep- tions, thus missing important growth opportunities in the construction sector. Kozak and Cohen (1999) found that there is room to improve the competitiveness of wood products in the North American construction sector, but that regional differences must be taken into account. They suggested creating targeted campaigns that focus on regions of North America that are “wood friendly”, such as western North America, to start. Hammon (2016) and Laguarda Mallo & Espinoza (2015) highlighted that architects or end-users who were most familiar with wood (or specific wood products) were least concerned with potential obstacles or barriers to wood construction. Laguarda Mallo & Espinoza (2015) suggested that the success of CLT will greatly depend on the information about the material being disseminated to architects. Another study identified drivers of material selection, and found that architects’ knowledge of wood (e.g., physical, mechanical, and environmental properties), experience with the use of wood, perceived control of the use of wood, and attitudes toward wood used structurally in buildings three stories or higher, were all statistically significant influencers of architects’ specifica- tion of wood products in urban construction (Bysheim & Nyrud 2009). 121 BioProducts Business 3(10) 2018 4. Methods 4.1 Setting and subjects This study focused on American Institute of Architects (AIA) certified architects located on the US West Coast (i.e. California, Oregon, and Washington). AIA is the lead- ing professional membership association for licensed architects and one of the most active organizations in connecting architects with continuing professional edu- cation programs (Roth, 2015). Therefore, this population was chosen as relevant for this study. A list of contacts was generated by the researchers using information from websites for all of the Washington, Oregon, and California AIA chapters. This is the most inclusive list available. Only one architect per architecture firm was contacted, with priority on the principal or main contact for the firm. This was, most likely, one of the people in the firm with a more extensive experience in using a broad range of construction materials and products, while the other people were excluded in the survey, to avoid duplicating some results about familiarity and use (see Table 1) due to architects in the same firm referring to the same project (i.e., questions on a firm’s specification of wood products and use of building systems). Some architects in this region may not have been included if they were not listed on their AIA chapter website or did not have an available email. However, since the number of architects that could be possibly excluded from this study is unknown to the authors, it is difficult to evaluate its impact on the validity of the results. A total of 3,469 architects were identified, 297 from Washington, 172 from Oregon, and 3,000 from California. 4.2 Data collection The questionnaire was administered online through the platform Qualtrics, and the questionnaire link was distrib- uted through the emailing system MailChimp. Because the research involved human subjects, Institutional Review Board (IRB) approval at Oregon State University was obtained before distributing the questionnaire. Data was collected between June and November of 2017. Following an adaption of the Tailored Design Method (Dillman et al. 2014), three rounds of emails were sent to each architect, each round was two to three weeks apart. 4.3 Questionnaire The questionnaire was developed for use in a broader international study with regional focuses on the US West Coast, Central and Eastern Europe, and Sweden (Markström et al. 2018). Questionnaire topics covered familiarity and perceptions of wood products, as well as the perceptions of the sustainability of wood products. However, in this paper we report only on familiarity and perceptions of wood products. Questionnaire items were generated by researchers across these regions, incor- porating and building upon questions from previous wood product perception studies (Kozak & Cohen 1999; O’Connor 2004; Robichaud et al. 2009). Questionnaire items were worded equally in positive and negative formats as a means of minimizing any bias from re- searchers. Items in the questionnaire utilized 5-point, Likert-type scales, multiple choice, and short answer options. All questions had an “unsure” option to prevent respondents from providing incorrect information on questions, and to be able to differentiate on Likert-type scale questions between respondents who were unsure about a question versus respondents who were sure but had a neutral response. A focus group for this specific study was held with regional experts in wood science, forest products market- ing, civil engineering, and architecture, to further refine the questionnaire for the US West Coast. The question- naire was also pretested with four architects within the target audience (Dillman et al. 2014). Their feedback helped to improve clarity and validity (Vaske 2008) to better coincide with the terminology architects use. Responses from the pre-test were not included in the final results. This study focuses on five topics: familiarity and use of wood products, advantages and weaknesses of wood products, perceptions of wood product use, how architects gather information, and respondent demographics (Table 1). Among these, the first two sections address the first research objective: “Provide an update on the current state of US West Coast architects’ familiarity, use, and perceptions of wood products”. Goal of questions in the third section is to identify what US West Coast architects currently perceive as the most prominent advantages and disadvantages of using wood products (2nd research objective). The last section of the questionnaire aims to identify how US West Coast archi- tects prefer to gather information about materials, and what additional information they need to incorporate wood into their designs (3rd research objective), and consequently identify possible approaches to effectively deliver information about wood construction materials among architects (4th research objective). Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 122 4.4 Data analysis General data analysis was conducted using descrip- tive statistics. Differences among respondents based on location and experience level were analyzed using ANOVA. Descriptive data analysis of questionnaire items was conducted using Microsoft Excel (Microsoft 2013). Statistical analysis was conducted using the software SPSS (version 24.0; 2016). All statistical analysis used α=0.05 for significance levels. One-way ANOVA was used on items comparing groups of architects by state or years of experience. Scheffe’s post-hoc test was used with groups exhibiting equal variance and Tamhane’s T2 post-hoc test for groups exhibiting unequal variance. Levene’s test for equality of variance was used to compare if architects who collaborate with engineers are more familiar with engineered products than architects who do not collaborate. Items requiring respondents to rank items were ana- lyzed using the Modified Borda count method (Emerson 2013). In a Modified Borda count, respondents rank ‘x’ number of items, the item they rank first receives a count of (x), the item they rank second receives a count of (x-1), the item they rank third receives a count of (x-2), and so on until the ‘x’th item receives a count of (1) (Emerson 2013). The responses to the short answer question asking respondents to list three weaknesses of wood products were grouped to find reoccurring themes. Groups used for this were modeled after simi- lar questions in related studies (Markström et al. 2018; O’Connor et al. 2004), using their top categories for wood product disadvantages or weaknesses, including: ‘fire resistance’, ‘acoustic performance’, ‘code’, ‘performance/ strength’, ‘decay/durability’, ‘difficult to design’, ‘quality’, ‘shrinkage’, ‘economics/cost’, and ‘labor skill’. Additional Table 1 List of Questionnaire items and related research objectives. Research Objective Topic Question Type1 Demographic Where is your practice located?2 (MC) What percent of your projects are located in [selected location]? (MC) What is your position at your company? (SA) How many years of professional experiences do you have? (MC) 1) Provide an update on the current state of US West Coast architects’ familiarity, use, and perceptions of wood products Familiarity and Use Are you familiar with the following products? And have you used them? (LS) (MC) Please rank the following structural engineered wood products that you are familiar with from most familiar to least familiar3 (R) Please rank the following non-structural engineered wood products that you are familiar with from most familiar to least familiar3 (R) Please rank the building systems that you use most (R) Perceptions of use In your opinion, in the last 5 years the use of wood products in the following types of construction has… (LS) In your opinion, over the next 5 years the market for the following construction materials in the Pacific Northwest will… (LS) 2) Identify what US West Coast architects currently perceive as the most prominent advantages and disadvantages of using wood products. Advantages and Weaknesses Please select 3 advantages of wood products that are most important to you (S) Please indicate the degree to which you agree with the statement: Wood can be a durable material (LS) Please list three weaknesses of wood products (SA) 3) Identify how US West Coast architects prefer to gather information about materials and what additional information they need to incorporate wood into their designs. 4) Identify approaches for the wood products industry to deliver information and address identified knowledge needs of these architects. Information Do you believe you have enough information about wood products to integrate them into your building designs? (MC) Do you collaborate with engineers who have expertise in timber design? (MC) Please indicate what additional information about engineered wood products you would like to have: (S) Please select the 5 tools for obtaining information about materials that are the most valuable to you. Then, rank those 5 tools in order from most valuable to least valuable. (R) 1. Question types: MC = multiple choice, LS = Likert-type scales, R = ranking, S = select all that apply, SA = short answer 2 This question was used for screening at the beginning of the questionnaire, to make sure the sample only included the target population. 3. Engineered wood products that are commonly used in residential construction (e.g., plywood, oriented strand board, particleboard) were excluded from this question. 123 BioProducts Business 3(10) 2018 categories were created for responses that did not fall into categories defined by previous studies including: ‘availability’, ‘aesthetics’, ‘perception/demand by client’, ‘lack of information’, ‘maintenance’, and ‘Glues/VOCs’. Unsure responses for all questions were not included in the statistical analyses. However, questions with high percentages of unsure responses were identified and reported where appropriate. 4.5 Response rate Out of the 3,469 architects emailed, 263 emails bounced (i.e., delivery failure), and 533 architects completed the questionnaire resulting in an adjusted response rate of 16.6%. Other similar studies report response rates from architects being 7% to 22.7% (Gaston 2014; Kozak and Cohen 1999; Laguarda Mallo & Espinoza 2015; Markström et al. 2018; O’Connor et al. 2004). Washington and Oregon had higher response rates than California, of 25% and 42% versus 14%, respectively. The questionnaire did not require respondents to answer every question, result- ing in sample sizes per item varying from 533 to 304. In general, the sample sizes per question trended higher to lower, from the beginning of the questionnaire to the end. There did not appear to be one particular question that caused respondents to stop. 4.6 Non-response bias A common concern with questionnaires is that non- respondents would have completed the questionnaire differently than those who did respond, resulting in a non-response bias (Dillman et al. 2014). To check if there was difference in responses from architects who completed the questionnaire from those who did not, a shortened questionnaire containing four of the original 22 items was sent to architects that had not responded, resulting in 48 respondes. Statistically significant differ- ences were found for the respondents’ locations, there were fewer architect’s from California in the non-respon- dent group (p=0.04) than the initial respondent group. Respondents in the non-respondent group indicated a significantly higher use of one out of the 19 wood products (glulam, p<0.01) than the initial respondent group. No significant difference was found for the other 18 products, which does not suggest any significant difference among the two groups. T-tests revealed no statistically significant differences between the groups of respondents for the rest of the shortened survey; which included years of experience, type of building systems primarily used, familiarity of types of wood products and use of wood products. The results of this work may need to be interpreted understanding that California may be underrepresented (as evident from the lower response rate in California for the full questionnaire); other areas showed no substantive non-response bias. 5. Results & Discussion 5.1 Respondent demographics Of the 533 completed questionnaires, 13% (71) were from Washington, 12% (64) were from Oregon, and 75% (398) were from California. Seventy-eight percent of respondents indicated that most (76-100%) of their projects are located in the same state as their firm (n=533) (Table 2). Sixty-two percent (244) of respondents held a principal or other management role at their firm. Other respondents included designers 17% (66), designer/ managers 18% (70), and technical roles 3% (12) (Figure 1). Overall, respondent experience level was high, aligning with most of them being the principal of their firm. Of 0 50 100 150 200 250 Fr eq ue nc y Figure 1. Respondent’s role at their firm. (n=392). Table 2. Where respondent’s firms are located, and percentage of respondents’ projects located in same state as the firm. What % of projects are located in the same state as respondents’ firms Location 0-25% 26-50% 51-75% 76-100% Total Washington 0 2 11 57 71 Oregon 3 6 10 38 64 California 13 10 45 319 398 Total 16 18 66 414 533 Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 124 the 398 respondents, 62% (246) had more than 25 years of experience, 23% (93) had 16-25 years of experience, 12% (46) had 5-15 years of experience, and 3% (12) had less than 5 years of experience. 5.2 Familiarity and use There is a positive correlation between respondents’ familiarity and use of the 19 wood products included in the study (Figure 2). Responding architects’ familiarity with all wood products, when expressed in mean values of familiarity on a 5-point Likert-type scale, was at least a 2.5. This indicates that the responding architects were closer to being at least ‘moderately familiar’, than to be- ing ‘unfamiliar’, with all of the wood products included in the study. Dimension lumber, plywood panels, and oriented strand board (OSB) were the only three products that received a mean familiarity rating of a 4.5 or higher, showing the respondents were ‘very familiar’ with those products. All products that had an average familiarity rating of 3.5 (familiar) or higher, had been used by at least Figure 2. Respondent familiarity with various wood products versus if they have specified use of the product. Scatter plot showing mean values of familiarity and use of 19 wood products of all respondents. The x-axis displays familiarity, with 1 = “very unfamiliar” to 5 = “very familiar”, and the y-axis shows use, with 1 = “have not used” and 2 = “have used” (varying responses per product, n=449 to n=377). 75% of respondents. All products that had an average familiarity rating of 2.5 to 3.4 (moderately familiar) had been used by less than 43% of respondents. Generally, there was no relationship between years of experience and familiarity with wood products. Four of the 19 wood products did however show a statistically significant difference in familiarity based on how many years of experience an architect had (Table 3). The four products were sawn timbers, parallel strand lumber (PSL), light sandwich panels, and wood fiber insulation boards. Several other products showed a similar pattern, but it was not consistent across all products. This sug- gests that communication should be designed to reach architects at all levels of experience. When asked to rank familiarity with products in groups, respondents ranked glued-laminated timber (glulam) as the structural engineered wood product they were most familiar with; nail-laminated and dowel- laminated timber were ranked the lowest and were very 125 BioProducts Business 3(10) 2018 close to each other (Figure 3, left). For the non-structural engineered wood products group, low/medium/high- density fiberboards were ranked first, with thermally modified wood and light sandwich panels ranked the lowest and were very close to each other (Figure 3, right). Some of the wood products that respondents were less familiar with could potentially be attributed to the volumes or locations at which they are manufactured. For example, dowel laminated timber is not produced in a manufacturing setting on the US West Coast, thermally modified wood and wood plastic composite manufactur- ers are few. Glulam and laminated veneer lumber (LVL) manufacturers have a prominent presence along the US West Coast (APA, 2018). Additionally, some products have just recently been introduced in the North American market and have seen limited diffusion (e.g., CLT). Regarding common wooden building systems, the responding architects said they are most familiar with light frame/panel (e.g., platform, balloon), followed by engineering frame systems (e.g., glulam post-beam, hybrid systems) and timber frame (e.g., solid timbers) (Table 4). Other building systems such as cross-laminated timber (e.g., walls, floors, hybrid systems), log construc- tion, and other, were ranked as being considerably less familiar to the respondents, respectively. These findings are an updated report on architect’s familiarity with wood products. In 1999, Kozak & Cohen found that architects and structural engineers were most familiar with lumber studs, dimension lumber, and plywood, similar to the results of the present study; but were least familiar with structural insulated panels and PSL. In the present, architects were generally fa- miliar with PSL (mean = 4.15) with the product. A study in 2015 found that 57.5% of architects were ‘not very familiar’ or ‘had not heard about CLT’ (Laguarda Mallo & Espinoza, 2015). Three years later 83.1% of architects were ‘moderately familiar’ or more with CLT and 23.3% ranked CLT as one of their top three most common types of wooden construction they specified. This is a considerable increase and shows that lessons learned for effective communication to architects regarding CLT could be tailored for and transferred to other existing or new wood products in the future. It should also be noted that the percentage of respondents ranking CLT Table 3. Respondent familiarity with various wood products based on years of experience. Years of experience1 Product <5 5-15 16-25 25+ F-value Df p-value ETA Glued-laminated timber 4.50 4.17 4.45 4.53 2.50 392 0.06 0.14 Nail-laminated lumber 2.58 2.83 2.48 2.71 1.41 393 0.24 0.10 Dowel-laminated timber 2.25 2.48 2.48 2.56 0.48 390 0.70 0.06 Cross-laminated timber 3.75 3.48 3.28 3.51 1.48 391 0.22 0.11 Sawn timbers 4.00ab 4.07a 4.34ab 4.54b 5.66 390 0.01 0.20 Round wood 3.17 3.00 3.09 3.33 2.24 392 0.08 0.13 Parallel strand lumber 3.08a 3.80ab 4.26bc 4.24c 7.35 392 <0.01 0.25 Laminated strand lumber 3.92 3.91 4.23 4.16 1.26 392 0.22 0.11 Dimension lumber 4.83 4.78 4.80 4.78 0.02 392 0.99 0.02 Laminated veneer lumber 3.92 3.91 4.33 4.31 2.73 392 0.02 0.16 Plywood panel 4.75 4.74 4.78 4.70 0.15 388 0.79 0.05 Low/medium/high density fiberboards 4.08 4.33 4.54 4.46 1.50 387 0.14 0.12 Veneered particleboard 4.17 4.17 4.18 4.20 0.02 385 0.99 0.01 Particleboard 4.17 4.18 4.34 4.44 1.11 388 0.14 0.12 Oriented strand board 4.58 4.26 4.52 4.54 1.04 389 0.10 0.13 Light sandwich panel 2.33a 3.20ab 3.20b 3.28b 3.46 389 0.05 0.16 Wood plastic composites 2.83 3.20 3.42 3.44 2.04 391 0.15 0.12 Thermally modified wood 2.50 3.11 2.93 2.97 1.21 388 0.34 0.09 Wood fiber insulation boards 2.67ab 2.85ab 2.76a 3.18b 5.01 389 <0.01 0.18 1. Cell entries are means of respondents’ familiarity of different wood products: 1 ‘very unfamiliar’, 2 ‘unfamiliar’, 3 ‘moderately familiar’, 4 ‘familiar’, and 5 ‘very familiar’. 2. Means that have different letters for superscripts differ at a p < .05 for Scheffe’s post-hoc test for equal variance Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 126 Figure 3. Structural and non-structural engineered wood products ranked by familiarity using a Modified Borda count. Left: Structural engineered wood product results, maximum possible count for one product was 2877, seven products, n=411. Right: Non-structural engineered wood product results, maximum possible count for one product was 2020, five products, n=404. 127 BioProducts Business 3(10) 2018 as one of their most common types of construction is a strange result and should be investigated further since there should be a corresponding number of CLT build- ings built or in the design phase for this to be accurate. 5.3 Advantages and weaknesses of wood products When asked about advantages of wood products, re- spondents ranked ‘ease of use’, ‘aesthetics’, and ‘cost’ as the top three advantages of wood products (Table 5). Fire resistance and health tied for last. Responding architects in different states ranked the advantages only slightly differently, all three groups ranked ‘ease of use’, ‘aesthet- ics’, and ‘cost’, in the top three and had ‘fire resistance’, and ‘health’ somewhere in the last three positions. The attribute ‘ease of use’ was included by the researchers to mean designing with wood could be done with ease. It could have been interpreted by respondents differently as it is a less common phrase than the other attributes. Interestingly, although ‘cost’ was in the top three advantages for wood products, 15% of respondents indicated it was a weakness of wood products. In 2015 another study in the same geographic location, respond- ing architects identified cost as one of the biggest issues for wood products (Roth, 2015). Cost being reported as both a high-ranking advantage and as a weakness could be due to some wood products and building systems (e.g., glulam, timber frame) having higher relative costs Table 5. Ranking of different advantages of wood products regarding how important they are to responding architects across and between states. (n=413). State Total Washington Oregon California Advantage Rank MBC1 Rank MBC1 Rank MBC1 Rank MBC1 Ease of use 1 599 2 90 2 65 1 448 Aesthetics 2 559 1 98 1 67 3 400 Cost 3 547 3 73 3 63 2 414 Environmental impact 4 270 4 57 4 39 5 175 Seismic performance 5 193 6 7 6 9 4 178 Strength 6 190 5 24 5 16 6 151 Fire resistance 7 47 6 7 8 3 7 37 Health 7 47 8 4 7 8 8 35 1. MBC =Modified Boarda Count Table 4. Type of common wooden building systems respondents reported being most familiar with. (n=396). Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 128 compared to traditional building materials, such as steel and concrete, and others (e.g., dimension lumber, light frame) having much lower relative costs. The top categories for weaknesses of wood products listed by responding architects were ‘decay/durability’ in- dicated by 61% of respondents, ‘fire resistance’ indicated by 48% of respondents, and “performance/strength’ indicated by 39% of respondents (Table 6). Regarding durability, although it was the most frequently indicated weakness of wood, 74% of respondents indicated, in a separate questionnaire item, that they agree with the statement “wood can be a durable material”. Therefore, it is possible that the responding architects believe that this weakness can be overcome with proper design and treatments. An interesting difference of weaknesses reported by state included: ‘decay/durability’ where respondents indicating ‘decay/durability’ as a weakness in Washington (64%) was lower than in Oregon (78%) and California (79%). Other slight differences were seen in ‘quality’. Architects in Washington (13%) and California (19%) were more critical than in Oregon (5%) regarding the ‘quality’ of wood products. Some examples of responses grouped in the ‘quality’ category included: “grade qual- ity diminishing”, “quality is going down”, “guaranteeing that millwork is built to design intent”, and “hard to maintain universal quality over a large quantity of one product type”. These responses included concerns about quality at the material, product and built system level. Successfully increasing the use of wood products will require manufacturers and contractors to address the quality concerns of their stakeholders. Other researchers identify prefabrication and modularity (e.g. Johnsson & Meiling, 2009; Koppelhuber et al., 2017), BIM – Building Information Modeling (Aberger et al., 2018; Le Roux et al., 2016) and digital fabrication (Schindler, 2007) as fac- tors that could, and are, moving the wood construction industry towards increased quality control in all stages of design and production. Overall the advantages and weaknesses indicated by responding architects were similar to those of past studies. Advantages have largely remained the same over the years with aesthetics, ease of use, and costs being rated highly (Kozak & Cohen, 1999; O’Connor et al., Table 6. Weakness of wood products as indicated by respondents1. State Total WA OR CA Weakness (n=347)2 (n=45)2 (n=37)2 (n=265)2 Decay/Durability 267 77% 29 64% 29 78% 209 79% Fire Resistance 168 48% 19 42% 19 51% 130 49% Performance/Strength 134 39% 16 36% 16 43% 102 38% Dimensional stability 60 17% 9 20% 4 11% 47 18% Quality 58 17% 6 13% 2 5% 50 19% Environmental concern 54 16% 5 11% 8 22% 41 15% Cost 52 15% 7 16% 7 19% 38 14% Maintenance 40 12% 6 13% 4 11% 30 11% Codes 27 8% 7 16% 5 14% 15 6% Availability 21 6% 3 7% 1 3% 17 6% Perception/demand by clients 16 5% 4 9% 3 8% 9 3% Other3 16 5% 4 9% 1 3% 11 4% Glues/VOCs 15 4% 3 7% 1 3% 11 4% Labor skill 13 4% 2 4% 2 5% 9 3% Lack of information 11 3% 3 7% 2 5% 6 2% Aesthetics 9 3% 2 4% 1 3% 6 2% Difficult to Design 8 2% 3 7% 0 0% 5 2% Acoustics 3 1% 0 0% 1 3% 2 1% 1. Respondents were asked to each list 3 weaknesses, left column per group are frequencies, right column per group are percentages of architects in group who listed each weakness. 2. The n for each group is how many respondents who answered this question, not all respondents gave 3 weaknesses. 3. Other category includes weaknesses that were not mentioned at least 3 times. 129 BioProducts Business 3(10) 2018 2004). And disadvantages or weaknesses largely remain- ing the same with fire concerns, strength/performance and durability all being rated highly as concerns about use of wood products (Kozak & Cohen, 1999; O’Connor et al., 2004). There has not been significant change in perceptions of advantages and weaknesses of wood products in the last twenty years. Aesthetics, the second most highly ranked advantage by this study’s respondents, was reported as a ‘very im- portant’ or ‘important’ characteristic for material selection by 94% of architects in another study (Laguarda Mallo & Espinoza, 2015), and was rated as the most impor- tant attribute in another study (Gaston, 2014). While this could be a promising attribute of wood products, structural performance and durability were reported as more important characteristics architects look for in material selection, with 98.6% and 97.8% of architects rating them as ‘very important’ or ‘important’ (Laguarda Mallo & Espinoza, 2015). Durability and performance/ strength were in the top three mentioned weakness of wood products in the present study. Therefore, based on the responses from Laguarda Mallo & Espioza (2015), it is suggested that improving these particular charac- teristics of wood products, or the communication of these characteristics, could increase the likelihood of architects specifying wood. The weaknesses identified by respondents are similar to the barriers indicated by the general public in the US in a survey from Hammon (2016). In their study, the public on the Pacific coast considered flammability, forest depletion, and strength as the biggest barriers, showing us that these weaknesses, perceived or real, are consistent across different stakeholders of the con- struction industry. 5.4 Perceptions of wood product use Respondents believed that the use of wood products has remained the same in seven types of construction over the last 5 years (Figure 4). However, 34%-37% of respondents were ‘unsure’ about the past use of wood products in educational, institutional, civic, and higher education types of construction; 18% and 13% of respon- dents were ‘unsure’ about mixed-use and commercial (respectively), and only 4% of respondents were ‘unsure’ about residential. When breaking down these means by state it was found that generally respondents in California were more likely to have the opinion that the use of wood products has decreased in the last five years (mean = 2.26 – 3.26), except for in residential construction, where Oregon (mean = 3.11) was slightly lower than California (mean = 3.13) (Table 7). Respondents in different states showed statistically significant differences in their opin- ions of change in wood product use over the past five years for all building categories except for residential and commercial. Figure 4. Respondent opinions on use of wood products in various types of construction over the past five years separated by state. Chart showing means of respondent opinions of wood usage trends in seven types of construction over the past five years, not including ‘unsure’ responses (per type of construction for all respondents n=261 to 411; SD=0.65 to 0.97). Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 130 Table 7. Respondent perceptions of how use of wood products in building types have changed in the last five years, based on state. States1 Types of construction WA OR CA F-value Df p-value ETA squared4 (η 2 ) Residential 3.28 3.11 3.13 1.31 408 0.27 0.08 Commercial 3.31 3.25 2.97 3.81 362 0.02 0.14 Mixed-use2 3.60a 3.47a,b 3.26b 3.74 339 0.03 0.15 Institutional3 3.24a 2.97a,b 2.76b 5.50 265 <0.01 0.20 Civic3 3.22a 3.11a 2.72b 7.02 260 <0.01 0.23 Educational2 3.41a 3.33a 2.83b 10.50 272 <0.01 0.27 Higher Education2 3.27a 3.26a 2.75b 8.09 258 <0.01 0.24 1. Cell entries are means of respondents’ opinions of how wood use has changed in various buildings over the last five years: 1 ‘greatly decreased’, 2 ‘decreased’, 3 ‘remained the same’, 4 ‘increased’, and 5 ‘greatly increased’. 2. Means that have different letters for superscripts differ at a p < .05 for Scheffe’s post-hoc test for equal variance 3. Means that have different letters for superscripts differ at a p < .05 for Tamhane’s T2 post-hoc test for unequal variance 4. ETA squared ( η 2) is a measure of effect size for use in ANOVA Architects in Washington (mean = 3.22 – 3.41) and Oregon (mean = 3.11 - 3.33) were statistically significantly (f = 5.50 – 10.50, p < 0.01) more likely to think wood product use in civic, educational and higher education construction remained the same or increased slightly, than architects in California (mean = 2.83 and mean = 2.75) over the last five years (Table 7). Architects in Washington (mean = 3.60 & 3.24) were also statistically significantly (p = 0.147 & p = 0.200) more likely to think that wood use in mixed-use and institutional construc- tion remained the same or increased slightly over the last 5 years, than architects in California (mean = 3.26 & 2.76). In a study from 1999, only 8.9% of designers said they intended to use more wood in the future (Kozak & Cohen 1999). This went up fifteen years later, when a different study reported 32% of architects said they expected to use more wood in architectural elements in the next 5 years, while 62% expected to use the same amount in the future (Gaston 2014). Based on respond- ing architect’s perceptions of wood use in the last five years in the present study, the prediction from Gaston (2014) appears to have held true, and the trend for slow increases of wood use appear to have remained the same. Looking forward, respondents’ mean opinion was that the market for wood, steel, and polymers in the Pacific Northwest will grow over the next five years, while con- crete will remain stable (Figure 5). It should be noted that 27% of respondents were ‘unsure’ about polymers, while 8% or less were ‘unsure’ about the other three products (n=426 to 429). When segmented by state, Washington Figure 5. Projected market change for construction materials in the Pacific Northwest, by state. Chart showing respondent opinions about the growth or shrinkage of the market for four construction materials over the next five years in the Pacific Northwest, not including unsure responses (per type of construction for all respondents n=311 to 403; SD=0.71 to 0.87). 131 BioProducts Business 3(10) 2018 respondents predicted wood use and concrete use to grow, while Oregon respondents predicted only wood use to grow, and Californian respondents predicted wood use, steel use, and polymer use to all grow (Table 8). The differences among respondents from different states suggests slightly different trends in wood use in different types of construction. Wood product manu- facturers, distributors or others, which produce, sell, or promote products for particular types of construction could use this information to target particular locations. Stakeholders can also use this information to aim their communication efforts with architects in locations that already show momentum to use wood products, or with architects in locations with greater potential for increasing wood use. However, it should be noted that both of the results in this section are from questionnaire items asking re- spondents to predict market trends. These results could have been more accurate predictors of market trends if the questionnaire items asked respondents to indicate projections of their own future material use. 5.5 Information Three-quarters of respondents collaborate with engi- neers that have wood design expertise, 16% do not, and 9% were unsure if they did (n=432). When compar- ing these results to the respondents’ familiarity with structural engineered wood products, respondents who collaborate with engineers that have expertise in timber design are more likely to be familiar with engineered wood products than those who do not. Respondents who collaborate with engineers that have expertise in timber design are statistically significantly more likely to be familiar with glulam, nail-laminated timber, CLT, PSL, and LVL, than those who do not (t-value = 2.138 to 3.681, p = 0.035 to <0.001) (Table 9). Effect size for all these products (rpb=0.118 – 0.178) was between small and medium (Cohen 1988). Seventy-eight percent (310) of respondents said that “yes” they have enough information about wood products to integrate them into their building designs, 13% (51) said no, and 9% (35) said they were unsure (n=396). Respondents who believe they have enough Table 8. Respondent perceptions of how the market for different construction materials in the PNW will change in the next five years based on state. States1 Material WA OR CA F-value Df p-value ETA squared4 (η 2 ) Wood3 4.03a 3.98a 3.54b 13.34 400 <0.01 0.25 Concrete 3.54 3.29 3.48 2.02 389 0.13 0.10 Steel2 3.46ab 3.17a 3.51b 6.14 391 <0.01 0.18 Polymers 3.45 3.47 3.73 3.11 308 0.05 0.14 1. Cell entries are means of respondents’ opinions of how the market for different construction materials in the PNW will change in the next five years: 1 ‘significantly shrink’, 2 ‘shrink’, 3 ‘remain stable’, 4 ‘grow’, and 5 ‘significantly grow’. 2. Means that have different letters for superscripts differ at a p < .05 for Scheffe’s post-hoc test for equal variance 3. Means that have different letters for superscripts differ at a p < .05 for Tamhane’s T2 post-hoc test for unequal variance 4. ETA squared ( η 2) is a measure of effect size for use in ANOVA Table 9. Familiarity with structural engineered wood products based on respondent collaboration with engineers who have expertise in timber design. Do you collaborate with engineers who have expertise in timber design? Products Yes (83%) No (17%) t-value p-value Effect size (rpb) Glue-laminated timber 4.51 4.25 2.35 0.02 0.12 Nail-laminated lumber 2.74 2.27 3.68 <0.01 0.16 Dowel-laminated timber 2.54 2.39 1.15 0.25 0.06 Cross-laminated timber 4.51 4.25 3.56 <0.01 0.18 Parallel strand lumber 4.25 3.94 2.14 0.04 0.13 Laminated strand lumber 4.18 4.04 1.05 0.30 0.05 Laminated veneer lumber 4.33 4.00 2.72 0.01 0.14 Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 132 information about wood products to integrate wood into their designs are typically the same that collaborate with engineers that have expertise in timber design (Table 10). These findings highlight the importance of collaboration between the two main technical specifiers, architects and engineers, to increase the use of advanced engineered wood products as structural materials. This is also relevant to expand use of wood in non-residential applications, since the above mentioned wood products are mainly used in mid- to high-rise buildings and large span structures. If the wood products industry wants to capitalize and even foster collaboration between archi- tects and engineers, inter-disciplinary communication models should be developed, overcoming jargon and disciplinary structures (e.g., across professional organi- zations and schools). There was not a significant relationship between responding architects having enough information and their years of experience. It should also be noted that of the 310 respondents that indicated they have enough information about wood products to integrate them into their designs, 67% (208) ranked ‘light frame/panel (eg. Platform, balloon)’ as the building system that they use most. The most frequently selected additional information responding architects would like to have about wood products, was ‘technical information’ (Table 11). However, a little less than one third of respondents who answered this question indicated they would like no additional information. This indicates that there are no specific knowledge needs perceived by responding architects. This may also be an indicator of how receptive this group of professionals could be to receiving more information about wood products. The sources of information tools respondents indicat- ed were the most valuable were internet searches, manu- facturers, continuing education, consultants, professional associations, and colleagues (Table 12). Internet searches received a much higher count than other options, with 85% of responding architects ranking it somewhere in their top five most valuable sources (n=381). In a study from 1997, responding architects indi- cated that manuals, reading materials, and continuing education were the most influential methods for obtain- ing product information; and association promotion, computerized information, and proactive marketing were the least influential (Kozak & Cohen 1997). A little Table 10. Comparison of frequencies of responses if respondents have enough information about wood products and if they collaborate with engineers who have timber design expertise. Collaborates with engineers who have expertise in timber design Ye s No Un su re Has enough information about wood products to use them Yes 251 33 25 No 26 22 3 Unsure 22 8 5 Table 11. What type of additional information respondents would like to have about wood products. (n=390). Type of Information # of times item was selected % of respondents that selected item Technical information 207 53% Direct contacts with manufacturers 142 36% Visits to built objects 114 29% Visits to building sites 105 27% Other 33 8% None 118 30% Table 12. Most valuable sources of information about materials. A higher Modified Borda Count (MBC) indicates a tool being more valuable. (n=381). Tool MBC Internet search 1234 Manufacturers 759 Continuing education 703 Consultants 663 Professional Associations (AIA, etc.) 523 Colleagues 521 Conferences 260 Researchers 149 Newsletters 113 Owners 60 Developers 52 Contractors1 23 Other2 20 Trade publications1 10 1. If a respondent selected “other” they had the option to specify; contractors, and trade specifications were specified frequently, these two items were not a listed choice in the questionnaire. 2. The “other” category shown here is the count for “other” less the count for when “other” was specified as contractors or trade specifications. more than a decade later, in 2009, responding architects indicated that design manuals, physical examples, and design or company specific internet sources were among the most effective sources of information about wood products; and scientific papers, personal sales calls and 133 BioProducts Business 3(10) 2018 internet discussion forums were among the least ef- fective (Robichaud et al. 2009). Now roughly another decade later, in the present study, internet searches have gone from being the least influential source to being the most important. Additionally, a study in 2014 found that internet searches and professional associations were responding architects’ preferred way for finding continuing education courses (Roth 2015). Continuing education courses were another top ranked source of information by respondents in the present study, and another place where architects can learn about new products, material properties, new building methods, etc. However, since the majority of responding archi- tects claim they have enough information about wood products, they will unlikely search for additional informa- tion. Without additional information their perceptions on specific limitations and disadvantages of wood as a construction material, will likely remain unchanged. If the wood products industry wants to remove barriers limiting wood use in buildings, a stronger internet pres- ence alone may not be sufficient; inter-disciplinary com- munication and participation in continuing education initiatives may also be necessary. Indeed, the architects in this study also indicated they value information from manufacturers, providing a case for manufacturers to host continuing education courses for architects, ideally with engineers, and improve their internet presence, which historically has been lacking (Sowlati, 2013). This is also supported by a finding from Roos et al. (2010) that architects desired more engagement with wood product suppliers for solutions. 6. Conclusion AIA certified architects across Washington, Oregon, and California were surveyed in 2017. As might be expected, familiarity with a product and specification by architects go hand-in-hand. Products that respondents were most familiar with and used the most tended to be prod- ucts traditionally used in residential construction and manufactured along the US West Coast. Manufacturers and distributors could benefit from communicating technical information to architects on the US West Coast regarding the products respondents were least familiar with (dowel laminated timber, nail laminated timber, thermally modified wood, and light sandwich panel). Responding architects’ perceptions of advantages and weaknesses associated with using wood have remained consistent in the last two decades. Respondents had a positive outlook towards the most frequently reported weakness (durability), with a majority of them agree- ing that wood can be durable. Innovations in wood durability, and in other fields addressing other weak- nesses identified by the respondents, could lead to an increase in wood use. Change in the amount of wood used in different types of construction as perceived by the respondents, was fairly stable, with minimal change. Predictions for different materials used in construc- tion in the next five years indicates that respondents in Washington and Oregon predict more growth for wood products than Californian respondents, whom pre- dicted a higher growth for polymers. Lastly, the sources architects value most for gathering information about building materials have evolved, which means the way industry communicates with architects must evolve as well. To increase wood use, it is recommended that the forest products industry improves its internet presence, developing inter-disciplinary communication strategies. Last but not least, information not only must be more accessible to architects interested in specifying wood, but should reach also those architects who will not spontaneously search for this information, since many do not recognize their lack of knowledge. 6.1 Recommendations for future research The information in this study should be periodically read- dressed to ensure that communication is relevant, and efforts are successful in reaching the architecture com- munity. Future research could be conducted to address how architects’ educational background and participa- tion in continuing education affects their perceptions of wood products as well as how their familiarity and perceptions affect their specification of wood products. Future work could also address architect’s perceptions of the usefulness of social media as a means for receiving information from the wood products industry. 6.2 Limitations While there could have been room for multiple interpre- tations on some measurement items in this study, the pretest process reduced the probability confusion. One particular instance of this was in the question regard- ing different building types designed by respondents. Recommendations from the expert group were followed to define the different categories of building types, how- ever, we are aware that some categories can be seen as Conroy et al. — Familiarity, Use, and Perceptions of Wood Building Products: A Survey Among Architects on the US West Coast 134 overlapping, (e.g., post and beam with CLT panel floors, a hybrid system, could be categorized as engineered frame or cross-laminated timber). Additionally, inclusion of a non-wood building type category would have provided a better overview of the big picture. It is also possible that architects with a connection to wood, or to the university conducting the research, were more likely to complete the questionnaire. This could explain the higher response rate in the state of Oregon. Although California may be underrepresented in this study (as evident from its lower response rate) a significantly higher number of respondents (75%) were from California. This can be a potential source of bias, since codes and standards in this state, such as those related to seismic design, are particularly restric- tive (e.g., California Building code, 2016). Despite these limitations, this study provides evidence that there is a need for improving wood products communication on the US West Coast. It also provides a framework for future statistical analysis in the field of wood product architectural surveys. 7. Literature Cited Aberger, E., Koppelhuber, J., Heck, D. 2018. Building Information Modeling in timber construction – a solution for planning process, design phases and the unification of scope of works. In Proceedings of the 2018 World Conference on Timber Engineer- ing, August 20-23, Seoul Republic of Korea. Adair, C., McKeever, D., Gaston, C., Stewart, M. (2013). Wood and other materials used to construct non-residential buildings in the United States 2011. The Engineered Wood Association (APA). APA. (2018). Structural panel & engineered wood yearbook. The Engineered Wood Association (APA). Asdrubali, F., Ferracuti, B., Lombardi, L., Guattari, C., Evangelisti, L., & Grazieschi, G. (2017). A review of structural, thermo- physical, acoustical, and environmental properties of wooden materials for building applications. Building and Environment, 114, 307-332. Bayne, K., & Taylor, S. (2006). Attitudes to the use of Wood as a Structural Material in Non-residential Building Applications: Opportunities for Growth. Forest and Wood Products Research and Development Corporation, Victoria, Australia. Buchanan, A. (2016). The challenges for designers of tall timber buildings. In proceedings: World Conference in Timber Engineer- ing (WCTE). Vienna, Austria. Bysheim, K., Nyrud, A. Q. (2009). Using a predictive model to ana- lyze architects’ intentions of using wood in urban construction. Forest Products Journal. 59(7/8):65-74. California Building Standards Code (California Code of Regula- tions, Title 24). 2016. California Building Standard Commission. Cohen, J. (1988). Statistical power analysis for the behavioral sci- ences. Hillsdale, NJ: Erlbaum. Dillman, D. A., Smyth, J. D., & Christian, L. M. (2014). Internet, phone, mail, and mixed-mode surveys: the tailored design method. John Wiley & Sons. Emerson, P. (2013). The original Borda count and partial voting. Social Choice and Welfare, 40(2):353-358. Forest Products Lab, (2010). Wood Handbook: Wood as an Engineer- ing Material. U.S. Department of Agriculture. Forest Service, Madison, Wisconsin. Gaston, C. (2014). Visual Wood Product Trends in North American Non-residential Buildings. Forest Products Journal, p. 107-115. Gaston, C., Kozak, R., O’Connor, J., & Fell, D. (2001). Potential for increased wood-use in North American non-residential mar- kets. Forintek Canada Corp. Gupta, R. (2005). Stop knocking on wood and get real--Become a complete structural engineer. STRUCTURE Magazine, March 2005, pp. 16-17. Goetzl, A., & McKeever, D. B. (1999). Building codes: Obstacle or opportunity? Forest Products Journal, 49(9), 12. Hammon, S. (2016). Tall Wood Survey: Identifying and Analyzing the Obstacles of Perception. Perkins & Will Research Journal. 8(1):25-47. Hawkins, D. I., Best, R. J., & Coney, K. A. (2007). Consumer behaviour. Tata McGrawhill. Hemström, K., Mahapatra, K., and Gustavsson, L. (2010). The percep- tions of Swedish architects and structural engineers towards use of wood frames in multi-story buildings. PHD Candidate. Mid Sweden University, Sweden. IBM corp. (2016). IBM SPSS Statistics for Windows, Version 24.0. Armonk, NY: IBM Corp. Janse, G. (2005). European Co-operation and Networking in Forest Communication. European Forest Institute. Johnsson, H., Meiling, J.H. (2009). Defects in offsite construction: timber module prefabrication. Construction Management and Economics. 27(7):667-681. Juslin, H., & Hansen, E. (2002). Strategic marketing in the global forest industries. Authors Academic Press. Karacabeyli, E., & Douglas, B. (2013). CLT Handbook-US Edition. FPInnovations and Binational Softwood Lumber Council, Point-Claire, Quebec. King, W. (1996). Adoption and diffusion research in marketing: an overview. In: Proceedings. Fall Conference. American Marketing Association, pp. 665-684. Kitek Kuzman, M., Sandberg, D. (2017). Comparison of timber- house technologies and initiatives supporting use of tim- ber in Slovenia and in Sweden – the state of the art. iForest. 10:930:938. Knowles, C., Theodoropoulos, C., Griffin, C., and Allen, J. (2011). Oregon design professionals views on structural building products in green buildings: implications for wood. Canadian Journal of Forest Research. 41(2):390-400. Koppelhuber, J, Bauer, B., Wall, J., Heck, D. (2017). Industrialized timber building systems for an increased market share – a holistic approach targeting construction management and building economics. Procedia Engineering 171 (2017) 333-340. Kozak, R.A. and Cohen, D.H. (1997). How specifiers learn about structural materials. Wood and Fiber Science. 29(4):381-396. Kozak, R.A. and Cohen, D.H. (1999). Architects and structural engineers: An examination of wood design and use in non- residential construction. Forest Products Journal. 49(4):37. Laguarda Mallo, M. F., and Espinoza, O. (2015). Awareness, per- ceptions and willingness to adopt cross-laminated timber by the architecture community in the United States. Journal of Cleaner Production. 94:198-210. 135 BioProducts Business 3(10) 2018 Lähtinen, K., Toppinen, A., Suojanen, H., Stern, T., Ranacher, L., Bur- nard, M., & Kuzman, M. K. (2017). Forest Sector Sustainability Communication in Europe: a Systematic Literature Review on the Contents and Gaps. Current forestry reports, 3(3), 173-187. Larasatie, P., Guerrero, J., Conroy, K., Hall, T., Hansen, E., & Need- ham, M. (2018). What Does the Public Believe about Tall Wood Buildings? An Exploratory Study in the US Pacific Northwest. Journal of Forestry, 116 (5) : 429-436. Le Roux, S., Stiegleier, M. 2016. Investigating the interaction of building information modeling and lean construction in the timber industry. In Proceedings of the 2016 World Conference on Timber Engineering, August 22-23, 2016, Vienna, Austria. Mayo, J. 2015. Solid Wood: Case Studies in Mass Timber Architecture, Technology and Design. Routledge. Markström, E., Kitek Kuzman, M., Bystedt, A., Sandberg, D., Fredriks- son, M. (2018). Swedish architects view of engineered wood products in buildings. Journal of Cleaner Production. 181:33-41. Microsoft, (2013). Microsoft Office Excel. Retrieved 2014 from: http://office.microsoft. com/en-us/excel/. Morsing, M., & Schultz, M. (2006). Corporate social responsibil- ity communication: stakeholder information, response and involvement strategies. Business Ethics: A European Review, 15(4), 323-338. O'Connor, J., Kozak, R., Gaston, C., & Fell, D. (2003). Wood Oppor- tunities in Non-Residential Buildings: A Roadmap for the Wood Products Industry (Special Publication No. SP-46). UBC and Forintek Canada Corp., Vancouver, Canada. O’Connor, J. (2004). Survey on actual service lives for North Ameri- can buildings. In Woodframe housing durability and disaster issues conference, Las Vegas (pp. 1-9). O'Connor, J., Kozak, R., Gaston, C., and Fell, D. (2004). Wood use in non-residential buildings: Opportunities and barriers. Forest Products Journal. 54(3):19. Oregon Forest Resource Institute (OFRI). (2017). Oregon Forest Facts 2017-18 Edition. Retrieved from: https://www.oregonforests.org/ sites/default/files/2017-05/OFRI_FactsFacts_1718_WEB.pdf. Polikar, R. (2006). Ensemble based systems in decision making. IEEE Circuits and systems magazine, 6(3), 21-45. Robichaud, F., Kozak, R., & Richelieu, A. (2009). Wood use in non- residential construction: A case for communication with architects. Forest Products Journal, 59(1/2), 57. Roos, A., Woxblom, L. & McCluskey, D. 2010. The influence of architects and structural engineers on timber in construc- tion – perceptions and roles. Silva Fennica 44(5): 871–884. Roth, T. (2015). Educational Needs Assessment of Designers in West Coast States: Architects. Oregon State University, United States. (M.S. Thesis). Schindler, C. (2007). Information-Tool-Technology: Contemporary digital fabrication as part of a continuous development of process technology as illustrated with the example of timber construction. Proceedings of the 27th ACADIA Conference 2007, Halifax, Canada. Showalter, J., Douglas, B., Kam-Biron, M. (2015). Changes to the 2015 National Design Specification (NDS) for wood construction and the inclusion of cross-laminated timber. ASCE. p. 2762-2767. Sinha, A., Gupta, R., & Kutnar, A. (2013). Sustainable Development and Green Buildings. Wood Industry/Drvna Industrija, 64(1). Softwood Lumber Council. (2018, May 8). Retrieved from http:// www.softwoodlumber.org/programs/softwood-non-resi- dential.html. Sowlati, T. (2013). Current and Future Role of Information Technol- ogy in the Global Forest Sector. In Hansen, E., Panwar, R., & Vlosky, R., The Global Forest Sector: Changes, Practices, and Prospects. Boca Raton: CRC Press.United States Department of Agriculture (USDA). (2016). California’s forest resources: forest inventory and analysis, 2001–2010. United States Department of Agriculture Forest Service. Vaske, J. J. (2008). Survey research and analysis: Applications in parks, recreation and human dimensions. Venture Publication. Washington Forest Protection Association (WFPA). (2018, May 22). Sustainable forestry. Retrieved from http://www.wfpa. org/sustainable-forestry/. Williamson, T., O'Connor, J., Martinson, K. L., (2009). Research, technology transfer, and education needs assessment for non- residential wood structures in California. General technical report FPL-GTR-183. Madison, WI: USDA-Forest Service, Forest Products Laboratory. p.10. Wood Works. (2018a, May 8). Why wood? Cost Savings. Retrieved from http://www.woodworks.org/why-wood/ Wood Works. (2018b, May 8). Innovations in Wood: Emory Point. Retrieved from http://www.woodworks.org/wp-content/ uploads/CS-Emory-Point1.pdf.