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Design+ Importance of material selection

regarding both material selection and sustainability criteria important, 3 – Average important, 4 – Very important,
according to any demographic characteristics. In this case, it is and 5 – Absolutely very important;
possible to generalize by determining the relative importance • A: The highest weight value (it is five in this case);
coefficients of the criteria. The following formula was used to • N: Total number of participants (it is 141 in this case).
calculate the relative importance index of the criteria: The relative importance index of the criteria for

IRI = ΣW/A*N (I) material selection is presented in Table 19. Accordingly,
Where: the most important criterion was the durability of the
• IRI: Index of relative importance; material, followed by the availability of the material and
• W: The weights given by each participant for that the availability of qualified labor. The popularity of the
proposition (1 – Not important, 2 – Somewhat material was regarded as the least important criterion.
The relative importance index of the sustainability
Table 16. Descriptive statistics according to participant’s criteria is presented in Table 20. The durability and
work experience maintainability of the material is the most important
criterion in terms of sustainability. Energy efficiency and
Work experience (years) Material mean Sustain mean cost-effectiveness were the next most important criteria
0 – 5 while being local was considered relatively the least
Mean 3.9361 3.7612 important criterion.
n 64 64 About 30% of the respondents claimed that they
6 – 10 would bear an additional cost ranging from 5% to 10% for
Mean 3.9122 3.7882 adopting sustainable materials (Figure 4). Twelve percent of
n 29 29 respondents said they would not pay more in this respect.
11 – 15
Mean 4.0606 3.7891 Table 19. Relative importance indexes of the criteria for
n 21 21 material selection
16 – 20 Rank Criterion Mean IRI
Mean 3.8283 4.0159 1 Durability of the material 4.7163 0.943
n 9 9 2 Availability of material 4.1773 0.835
More than 20 3 Availability of skilled labor force 4.1631 0.833
Mean 4.0966 4.1071 4 Sustainability 4.0142 0.803
n 16 16 5 Esthetics of the material 3.9929 0.799
Total 6 Ease of maintenance 3.9787 0.796
Mean 3.9614 3.8273 7 Ease of construction 3.8865 0.777
n 139 139 8 Construction speed 3.8723 0.774
9 Initial cost of material 3.8652 0.773
Table 17. ANOVA results according to participants’ 10 Maintenance cost 3.8652 0.773
occupations 11 Popularity of the material 3.1418 0.628

Sum of df Mean F Sig.
squares square Table 20. Relative importance indexes of sustainability criteria
Material mean
Rank Criterion Mean IRI
Between groups 3.090 8 0.386 1.412 0.197
1 Being durable and easy to maintain 4.5035 0.901
Within groups 36.108 132 0.274
Total 39.198 140 2 Being energy efficient 4.0851 0.817
3 Being cost-effective 4.0851 0.817
4 Being non-toxic 4.0426 0.809
Table 18. Kruskal–Wallis test results according to
participants’ occupations 5 Being renewable 3.8369 0.767
6 Being recyclable or being produced of recycled 3.3050 0.661
Kruskal–Wallis H df Asymp. sig. materials
Sustain mean 15.086 8 0.057 7 Being local 3.0355 0.607

Volume 2 Issue 1 (2025) 9 doi: 10.36922/dp.4491