Housing design during COVID-19: effects of psychological states on Japanese architecture students

Figures & data

Table 1. Questionnaire items, contents, and options.

Survey items	Survey contents and options
Q1. Current situation related to COVID-19	1–1. I am fearful of COVID-19 infection 1–2. I am anxious about attending university 1–3. I am anxious about going out 1–4. I am anxious about meeting my friends in person 1–5. Anxiety disorder due to COVID-19 *The response options for items 1–1 to 1–5 were (1) disagree, (2) neither, and (3) agree.
Q2. Activity time and sleeping time in a house before and during COVID-19	How did your time staying at home (including sleep times) change before and during COVID-19? 2–1. Weekdays 2–2. Weekends How did your sleep time at home change before and during COVID-19? 2–3. Weekdays 2–4. Weekends *The options from 2–1 to 2–4 are as follows: (1) < 6 h, (2) 6–8 h, (3) 8–10 h, (4) 10–12 h, (5) 12–18 h, (6) 18 h or more. 2–5. Did your sleep quality change during COVID-19 compared with before COVID-19? ※The response options for item 2–5 were (1) change, (2) neither, (3) no change. In the following examples, list the items in order of highest to lowest number of hours spent on each activity every day 2–6. Before COVID-19 2–7. After COVID-19 ※ The examples used in 2–5 and 2–6 are as follows: (1) Activities of daily living (rest, meals, etc.) (2) Sleep (3) Learning at school or cram school(face-to-face) (4) Personal learning (study, assignments, etc.) (5) Online learning (classes, studies, assignments, etc.) (6) Hobbies (dynamic: weight training, aerobic exercise, etc.) (7) Hobbies (static: reading, watching videos, etc.) (8) Interacting with others online
Q3. Housing design title	3–1. Tell me the title of the housing design.
Q4. Lighting equipment and color temperature plan	4–1. Select all the lighting fixtures used in each space. (1) Bracket light (2) Ceiling light (3) Chandelier (4) Downlight (5) Spotlight (6) Atrium light (7) Pendant light (8) Floor stand light (9) Task light (10) Footlight (11) Others 4–2. Select all the color temperatures of the lighting used in each space. (1) 3000 K (2) 3500 K (3) 4200 K (4) 5000 K (5) 6500 K
Q5. Space evaluation in design using the 7-level SD method	5–1. A feeling of being closed-in–A feeling of openness 5–2. Narrow–Wide (Spacious) 5–3. Dark–Bright 5–4. Warm image–Cool image 5–5. Quiet–Lively 5–6. Cramped–Cozy and relaxed 5–7. Unnatural feeling–Natural feeling 5–8. Private–Public * A 7-point Likert scale was used for the first item of each pair of descriptions: (1) strong feeling (2) general feeling (3) some feeling (4) neutral or neither agree nor disagree, AND for the second item of each pair(5) some feeling (6) general feeling (7) strong feeling
Q6. Window area and total floor area	Tell me the area (m^2) of the walls and windows close to each direction. 6–1. South 6–2. East 6–3. North 6–4. West 6–5. Ceiling wall.
Q7. Function of space	7–1. Awareness of introducing daylight 7–2. Ventilation considerations 7–3. Awareness of the connection with the outside world
	*The options from 7–1 to 7–3 are (1) disagree or (2) agree

Table

X, Y, Z	tristimulus values of a test stimulus calculated using the color-matching functions of the CIE 1931 standard colorimetric system (also known as the CIE 2° standard colorimetric system)
$Y_n$	tristimulus value, Y, of a specified white color stimulus calculated using the color-matching functions of the CIE 1931 standard colorimetric system
L*	CIELUV lightness
u*, v*	CIELUV u*, v* coordinates
u′, v′	CIE 1976 chromaticity coordinates
$u_n^{\prime },v_n^{\prime }$	CIE 1976 chromaticity coordinates of a specified white stimulus

Figure 1. Differences in stay-at-home-times before and during COVID-19, according to weekdays and weekends.

Figure 2. Differences in activities before and during COVID-19.

Figure 3. The proportion of participants feeling fearful of COVID-19 infection and anxiety about going out.

Figure 4. Results of the psychological evaluation according to the design image of housing space.

Table 2. Psychological evaluation according to the design image of housing space: correlations and descriptive statistics (r = Spearman’s rank correlation coefficient).

Variables	1	2	3	4	5	6	7	8
1. A feeling of being closed-in–A feeling of openness	1
2. Narrow–Wide	0.27	1
3. Dark–Bright	0.03	0.10	1
4. Warm image–Cool image	−0.08	−0.29	0.32	1
5. Quiet–Lively	0.14	−0.19	0.13	−0.01	1
6. Cramped–Cozy and relaxed	0.06	0.35	0.07	0.06	0.20	1
7. Unnatural feeling–Natural feeling	0.03	−0.13	0.47*	0.10	−0.05	0.01	1
8. Private–Public	0.60**	−0.02	−0.02	0.11	0.31	−0.03	−0.02	1

*Significant at p≤ 0.05, **Significant at p ≤ 0.01. Bold = r > 0.3

Figure 5. Relationship between “a feeling of openness–a feeling of being closed-in”/“private–public” and the design concept.

Table 3. ANOVA for the SD method by the items affected by the COVID-19 situation.

Source	Fearful of COVID-19 infection	About attending university	Anxiety about going out	Meeting my friends in person	Anxiety disorder due to COVID-19
A feeling of being closed-in–A feeling of openness	0.75	1.20	4.13*	6.55*	1.50
Narrow–Wide	2.22	1.13	0.66	0.21	1.20
Dark–Bright	1.73	1.16	1.39	0.33	1.31
Warm image–Cool image	3.78*	1.46	1.07	0.19	0.29
Quiet–Lively	1.79	1.58	1.54	1.93	2.36
Cramped–Cozy and relaxed	0.98	0.06	1.92	0.002	1.35
Unnatural feeling–Natural feeling	0.52	4.74*	0.16	1.17	1.12
Private–Public	0.48	0.66	5.12*	0.13	1.75

*Significant at p≤ 0.05, **Significant at p ≤ 0.01.

Table 4. ANOVA for the SD method by L*, V, and C.

Source	L* (Psychometric lightness)					V (Value)			C (Chroma)
	Base color	Sub color		Accent color		Base color	Sub color	Accent color	Base color	Sub color	Accent color
A feeling of being closed-in–A feeling of openness
	0.93		1.86		1.16	0.44	4.54*	1.01	2.10	0.01	0.04
Narrow–Wide
	1.52		0.01		0.004	1.06	1.01	0.03	0.99	10.73**	0.14
Dark–Bright
	6.46*		0.56		0.31	8.26**	0.22	0.57	3.54	0.12	0.19
Warm image–Cool image
	0.44		0.49		0.01	0.37	0.45	0.10	0.31	0.04	0.65
Quiet–Lively
	0.003		2.49		0.41	0.03	3.32	0.22	0.93	0.43	0.27
Cramped–Cozy and relaxed
	6.29*		3.27		0.26	4.27*	1.74	0.52	6.51*	3.92	0.19
Unnatural feeling–Natural feeling
	0.65		0.49		0.16	0.86	0.31	0.01	0.14	0.08	0.21
Private–Public
	0.80		0.30		0.11	0.77	0.49	0.09	2.76	2.15	0.01

*Significant at p≤ 0.05, **Significant at p ≤ 0.01.

Figure 6. Box plot of the L* values of the base color, sub color, and accent color.

Figure 7. Scatterplot of u*v* (a) base color, (b) sub color, (c) accent color.

Figure 8. Relationship between color temperatures and the psychological evaluation of the lighting used in the actual design; (a) dark–bright, (b) warm image–cool image.

Figure 9. Results of the correspondence analysis between lighting types and color temperatures.

Figure 10. WWR by gender; (a) South WWR, (b) sum of all the WWRs.

Figure 11. WWR for the number of windows; (a) South WWR, women, (b) South WWR, men, (c) sum of all the WWRs, women, (d) sum of all the WWRs, men.

Table 5. ANOVA for the WWR and number of windows.

Source	South WWR	East WWR	North WWR	West WWR	Ceiling WWR	Sum of all Orientation WWR	Number of Windows
A feeling of being closed-in–A feeling of openness	0.21	2.20	1.24	0.17	0.002	2.60	0.49
Narrow–Wide	1.06	0.004	0.004	0.19	0.002	0.04	0.75
Dark–Bright	0.23	2.61	4.25*	0.27	0.79	1.08	1.88
Warm image–Cool image	0.30	0.45	7.76**	0.32	0.78	2.53	0.17
Quiet–Lively	1.05	1.05	2.52	0.92	1.11	1.84	3.28*
Cramped–Cozy and relaxed	0.35	0.48	0.26	0.75	2.17	1.04	1.33
Unnatural feeling–Natural feeling	0.002	8.70**	0.01	1.26	2.97	0.19	1.12
Private–Public	0.04	1.10	0.85	0.00	0.81	2.38	0.71

*Significant at p≤ 0.05, **Significant at p≤ 0.01.

Figure 12. Total floor area and the number of windows.

Figure 13. Relationship between anxiety and housing design during COVID-19.