Regulating Indoor Comfortable Temperature Limits for Sustainable Architectural Design in Mediterranean Climates

Abstract

This study investigates sustainable living through minimizing environment impact, including energy efficiency, while supporting the well-being and thermal comfort in Mediterranean dwellings, specifically in Cyprus. This research highlights the need to define indoor temperature ranges that promote energy efficiency and occupants’ thermal comfort, considering the topographic variation in the Mediterranean climate. This study aims to promote sustainable building design by improving the occupants’ well-being in Mediterranean climates. This study uses the predicted mean votes index to determine thermal comfort limits by analyzing acceptable temperature ranges in 150 residences across different topographic areas of Kyrenia, Northern Cyprus, in summer and winter. The findings indicate that optimal interior air temperatures in the study area are 28.9 °C for summer and 20.2 °C for winter. Topographic variations highlight the importance of land elevation and microclimate differences in achieving suitable indoor thermal temperature conditions. The acceptable interior temperature range during summer in the mountainous region is wider (between 24.1 °C and 28.9 °C), while the winter range is broader in the coastal region (20.2 °C to 23 °C). This study provides novel region-specific indoor temperature guidelines for Mediterranean climates, emphasizing topographic differences and their influence on thermal comfort. The guidelines assist designers and policymakers in enhancing sustainable design in Mediterranean climates.

1. Introduction

Buildings consume half of their end-use energy for heating and cooling in order to ensure thermal comfort [1]. In practice, thermal comfort is defined as an absence of thermal discomfort [2]. Occupants who are uncomfortable with their inner space thermal surroundings are more likely to act in abnormal ways with lower potential to achieve their tasks and work [3,4]. In terms of sustainable design, architects and engineers need to consider and assess thermal comfort to ensure building occupants’ comfort while reducing energy usage [5].

Although many environmental factors affect indoor thermal comfort, like relative humidity and wind speed, air temperature inside the building is one of the main factors [6]. Air temperature is a crucial factor in assessing whether the indoor of a building is warm, cool, or thermally comfortable [7].

Active systems, or Heating, Ventilation, and Air Conditioning (HVAC) systems, were introduced and widely employed to satisfy standard thermal conditions and offer occupants a high level of thermal comfort [8]. Understanding the indoor accepted temperature ranges is one of the crucial requirements in designing HVAC systems inside the buildings to enable thermal comfort, energy-efficient HVAC systems, and sustainable design [9].

Therefore, defining a range of air temperatures that promote thermal comfort is essential for designing comfortable interior environments and has a significant effect on energy usage. Designers can considerably minimize energy use by properly sizing and selecting HVAC systems that maintain thermal neutrality while consuming less energy [10].

Environmental variables (air temperature, relative humidity, and wind speed) change due to the climatic characteristics and the diversity of topography and elevation above mean sea level [11]. This leads to changes in the level of indoor accepted temperature for achieving thermal comfort.

Previous studies addressed the differences in the ranges of indoor acceptable temperature limits in different climatic zones and revealed that the neutral temperature range or accepted temperature limits inside buildings were 22 °C to 28 °C in the hot and humid climate of Bangkok [12], from 22.5 to 30.6 °C in the composite climate of north India [13], and 20.2 to 20.9 °C in the temperate oceanic climate (Cfb) of Coventry, UK [14]. Moreover, the neutral temperature range ranged from 17.0 to 30.0 °C in Japanese subtropical indoors.

Furthermore, a comparison among previous studies also demonstrated the effect of the elevation above mean sea level on the accepted indoor temperature ranges.

In the hot and dry climate of the Garmian region in northern Iraq, where the elevation is 210 m above mean sea level and higher than the middle and southern parts, the range of indoor acceptable temperature was from 19.4 to 29.2 °C [9]. Whereas, in the rest of Iraq with a lower elevation (35 to 15 m) above sea level, the range was 25–35 °C [15]. Moreover, in the same climate in Shiraz city in Iran, which is above mean sea level by 1570 m, the range of accepted indoor temperature was from 22.0 to 25.0 °C [16]. These studies show that within the same climatic characteristics, the increase in the land height above mean sea level decreases the accepted temperature limits inside the buildings.

The unique characteristics of the Mediterranean climate in Cyprus are that it has hot and dry summers and mild and wet winters and different topographic regions with different microclimates, making this balance challenging for the designers. Therefore, in the current study, Kyrenia in North Cyprus, with its various topography and microclimate, has been selected as a study area. There is a lack of studies on the influence of topography and landforms on acceptable indoor temperature limits in Mediterranean climates.

This study tries to explore the effect of various landforms and topography in the Mediterranean climate of North Cyprus on indoor acceptable thermal temperature ranges for maintaining thermal comfort inside buildings. This is through developing indoor thermal comfort guidelines for residential buildings as the dominant building sector in the Mediterranean climate of Northern Cyprus [17]. This study aims to improve sustainable design criteria in buildings by enhancing occupants’ well-being and productivity in Mediterranean climates. This is through determining the threshold of acceptable temperature for maintaining thermal comfort and energy efficiency inside the buildings for summer and winter in this region while considering the various topography and regional landforms. This study tries to explore whether the indoor accepted temperature limits are changing according to topography and landforms in the Mediterranean climates and to what extent it can be significant in sustainable design. This research employs the predicted mean vote and predicted percentage of dissatisfied (PMV-PPD) index by looking at human and environmental factors, which can help to comprehend permanent thermal well-being within the frame of sustainability. This approach enhances energy efficiency and aligns with global sustainability targets, meeting the urgent need for climate-responsive architectural design in regions experiencing severe climatic changes [5].

2. Materials and Methods

2.1. Thermal Comfort Evaluation in Residential Buildings Through PMV-PPD Index

Thermal comfort is one of the most important needs for building occupants since it has a substantial impact on their overall comfort, health, and productivity [15]. The widely accepted international definition of thermal comfort is provided by ASHRAE Standard 55, which states, “Thermal comfort is the condition of mind that expresses satisfaction with the thermal environment” [6].

Residential buildings are known as common places to rest. Thermal comfort levels in residential buildings significantly impact occupants’ mental and physical well-being. For example, extreme temperatures in the house can cause various issues (sweating, fatigue, and skin allergies). As a result, an acceptable and comfortable indoor atmosphere should be regarded as essential to enhance occupants’ comfort, health, and well-being [18].

Previous research has concentrated on residential buildings, using field measurements and questionnaires to anticipate how people will react in certain circumstances within the buildings and at temperatures at which they will be comfortable. These temperatures are also known as ‘indoor accepted temperature’ or ‘indoor neutral temperature’. Ref. [19] observed that 90% of occupants accepted an interior air temperature between 22.0 and 25.9 °C. Ref. [20] showed the appropriate indoor temperature range of 10.2–22.9 °C, while [21] identified 25.6 °C (summer) and 19.8 °C (winter) as the average comfort temperatures. Residential buildings frequently provide a broader range of comfort or suitable environments for residents than offices [22,23], educational [24,25], or medical buildings [26,27]. This could be related to different thermal comfort requirements, less predictable activities, and more options for coping with the existing thermal environment [28].

Thermal comfort analysis can be carried out objectively or subjectively [29]. The focus of this study will be to objectively assess thermal comfort.

Therefore, objectively, thermal comfort can be evaluated depending on several factors, including environmental factors, air temperature, air velocity, relative humidity, mean radiant temperature, human factors, occupants’ activity levels, and clothing choices [30,31,32,33]. The PMV/PPD model, based on heat balance, is the most often used objective approach for evaluating thermal comfort [34,35]. This model has been approached because it is a well-known model and widely applied in active-mode and mixed-mode buildings (defined in the American National Standards Institute—ANSI/ASHRAE Standard 55) [6]. However, the free-running mode uses the adaptive method [32].

2.2. The Relationship Between Topography and Air Temperature in Shaping Building Sustainability

One of the main factors influencing how comfortable a person feels is air temperature [36], according to the widely accepted ASHRAE Standard 55 [6].

It is important to mention that elevation above mean sea level influences air temperature, leading to cooler conditions on northern slopes compared to southern slopes throughout the day in the Northern Hemisphere [37]. Moreover, landforms substantially influence air temperature [38]. In arid regions, particularly those under high pressure, the temperature can decrease by nearly 1 °C for every 100 m of elevation [39]. In addition, elevation influences thermal comfort, resulting in a temperature decrease of 0.8 °C for every 100 m increase in elevation. Refs. [40,41] found that the comfort temperature in a study of high-altitude residential buildings in India did not meet the ASHRAE criteria. As a result, they suggested a new comfort zone for areas with a comparable cold climate.

According to [42], in Cyprus, considering the geography and height, temperatures decrease by around 5 °C per 1000 m, along with maritime influences that result in colder summers and milder winters. The study highlighted that higher elevations witness cooler temperatures, which affects indoor thermal comfort and building design. In a study [43] in Turkey, it was determined that the 1179 m elevation difference between two sites led to physiological equivalent temperature (PET) decreases of 0.5 °C for each 100 m.

Therefore, the effect of topography is one of the factors that should be investigated and understood when indoor thermal comfort is a goal.

In the same context, air temperature affects human performance [31]. Many academics attempted to formulate a quantifiable correlation between temperature and human performance; for example, Ref. [44] indicated that performance dropped by 2% with a 1 °C increase in the 25–32 °C temperature range. In another study, Ref. [45] showed no such change in the 21–25 °C temperature range.

Refs. [46,47] found that call center personnel performed worse when the temperature exceeded 25 degrees Celsius. Ref. [48] designed three chamber environments with effective temperatures of 24 °C, 27 °C, and 30 °C. The findings indicated that the optimal temperature for most types of mental work was 24 °C, while for perceptual tasks, a reverse U-curve was identified, with the highest performance at 27 °C. Ref. [49] studied the relationship between time to finish a task and air temperature and discovered that at 26.7 °C, the task took the longest to complete while having the lowest rate of error.

Nonetheless, several studies have demonstrated that air temperature can indirectly affect human performance by influencing the frequency of symptoms of Sick Building Syndrome or air quality satisfaction [50,51].

Furthermore, Ref. [52] emphasizes how crucial air temperature is to thermal comfort models. They point out that temperature variations from the ideal range can cause discomfort, which raises energy use as residents try to adjust the setting using heating or cooling equipment. It is important to note that HVAC systems constitute a minimum of 50% of a building’s energy consumption to ensure a comfortable and acceptable indoor climate. Refs. [53,54] corroborate this, revealing that the utilization of air conditioning (AC) often increases average residential electricity consumption by 11%. Furthermore, AC greenhouse gas emissions will lead to a 0.5 °C rise in global temperatures. Refs. [55,56] indicate that energy usage for heating has consistently risen alongside developments in the building sector and a focus on indoor environmental quality.

Thus, through this review of literature, the importance of air temperature inside buildings on sustainability can be recognized through its effects on well-being, occupant productivity, and energy consumption in buildings.

2.2.1. The Relationship Between Accepted Thermal Temperature Limits and Energy Efficiency

Numerous field studies indicate that substantial energy savings can be achieved by increasing the cooling temperature setting and decreasing the heating temperature setting [15,57,58,59]. In the same context, the energy consumption of HVAC systems can frequently be lowered by 10% by an increase in indoor temperature of 1 K [60]. Within this context, the term “acceptable thermal temperature limits” (ATTLs) is the comfortable thermal state that generally describes the situation when the body perceives the thermal environment as being free of excessive warmth or cold [9]. Within this condition, the occupants will experience neutrality of thermal conditions. International standards such as ASHRAE 55 [6] and ISO 7730 [2] state that the temperature within buildings is within the acceptable range of 22.2 °C to 26 °C.

Previous studies demonstrated that the building occupants accepted thermal temperature (neutral temperatures) change according to the climatic zones. For example, in hot regions, neutral temperatures exceeded those in colder areas, and winter neutral temperatures were lower than summer temperatures within the same location [61,62]. This finding is frequently used in debates about indoor environments, where attempts are made to develop building and space designs that keep users at a comfortable temperature limit without requiring excessive heating or cooling. Moreover, studies showed that the residents’ satisfaction rises when they directly regulate thermal settings, such as the thermostat [63,64].

Therefore, in architectural and engineering fields, achieving an ATTL is crucial for designing sustainable buildings that provide energy efficiency and occupant thermal comfort [65].

The neutrality of thermal conditions might vary according to personal factors, such as the clothing worn by persons and the activities, in addition to the environmental factors such as humidity, air movement, and air temperature [66,67]. Since the environmental factors change according to the location on the planet and climatic zone [11], the ATTL changes according to the topography and the height from sea level.

2.2.2. Mediterranean Climatic Characteristics of the Study Area

The Mediterranean climate, classified as Csa/Csb in the Köppen system, represents a distinct subtype of subtropical climate [68]. The regions surrounding the Mediterranean Sea constitute the most extensive area exhibiting this climatic type. Regions characterized by Mediterranean climates typically experience moderate winters and exceedingly warm summers. Due to their proximity to large bodies of water, regions with a Mediterranean climate typically experience moderate temperatures with a relatively narrow range between winter lows and summer highs [69]. However, daily temperature fluctuations in summer can be significant due to dry and clear conditions, except along the immediate coasts [70].

Cyprus is located in the eastern Mediterranean Basin, between the latitudes of 34° and 36° N and the longitudes of 32° and 35° E [71]. Cyprus exhibits a quintessential eastern Mediterranean climate, marked by chilly to mild rainy winters and extended warm to hot dry summers [72]. In Cyprus, especially in inland regions during the summer months, the disparity between the highest daytime and lowest overnight temperatures is particularly noticeable. These daily variations in temperature vary from 8 to 10 °C in the lowlands and 5 to 6 °C in the mountains during the winter, up to 16 °C on the middle plain and 9 to 12 °C elsewhere during the summer [42,73]. The average daily temperature in July and August is between 29 °C in the central plain and 22 °C in the mountains, while the average maximum temperature during these months is between 36 °C and 27 °C. The average day temperature in January is 10 °C on the central plain and 3 °C in the mountainous areas, with average low temperatures of 0 °C and 5 °C, respectively. Relative humidity is strongly influenced by elevation above mean sea level and distance from the shore. Throughout the year, winter days and nights have humidity levels between 65% and 95%. Cyprus’s diverse topography produces microclimatic effects in different places. As a result, these characteristics must be taken into account when assessing the thermal comfort of buildings [42,73].

Kyrenia is situated along the northern coast of Cyprus, in the center of the island. The city is located at an elevation ranging from 2.5 m above sea level in the northern coastal area to approximately 300 m on the slopes of the Kyrenia mountain range, also known as (Beşparmak), in the southern region [40]. The geographical location is latitude 35.34° N and longitude 33.32° E. The average temperature is 10 °C in January, the coldest month, and 29 °C in July, the warmest month. In hilly regions, rainfall ranges from 750 mm to 500 mm, with winter and occasional summer precipitation. The Kyrenia Mountains receive the most rainfall, ranging from 750 to 1110 mm, due to their elevation. The case studies are selected within Kyrenia, a Mediterranean city, located between mountain chains of ‘Beshbarmak’ from the south and the Mediterranean Sea from the north. Figure 1 displays a map of Cyprus along with the study area [74].

2.3. Methodology

2.3.1. Criteria for Applied Method and Case Studies

This research employed a quantitative methodology and utilized comparative analysis to derive its conclusions. This was accomplished by gathering data from the site through direct observation to assess thermal comfort levels within the chosen case study buildings. Consequently, a case study methodology was adopted in the present research. See Figure 2.

This study employed comparative analysis to determine acceptable thermal temperature limits within residential buildings across various topographic and microclimatic regions during summer and winter. One hundred fifty existing residential buildings have been selected as case studies in Kyrenia. These buildings represent a variety of residential typologies, including apartment complexes and detached and semi-detached houses.

Kyrenia has been selected for this study, because of its various topographic characteristics that fall into three categories: mountainous, coastal, and hinterland (see Figure 3a). Therefore, coastal areas are recognized in the current study as the lands that are alongside the coastal frontline, and their elevation is between 2.5 m and 35 m above mean sea level. In the same context, hinterlands are the lands that are adjacent to the coastal land, and their elevations are between 47 and 100 m, while the mountainous area is the one that is above 150 m and lower than 300 m above sea level. See Figure 3b.

Fifty case study buildings were selected from each of the aforementioned topographic regions in different parts (see Figure 4), and they were limited to residential buildings. Furthermore, these case studies are limited to the first three floors to neutralize extra factors associated with height development, such as wind speed.

The buildings use mixed-mode systems, and at least one of the active heating or cooling systems (fans or air conditioners for summer and air conditioners or heaters for winter) was functional during the observation time. The convenience sampling technique was utilized for sample selection due to this study’s nature and circumstances. Additionally, direct observation was the approach used for collecting data. The measurements were taken at consistent times of the day (11:00 to 14:00) throughout the observation periods, which spanned around one month in summer and one month in winter, which are the region’s two extreme seasons in Mediterranean climates. Daytime was selected to involve solar radiation and shading factors during the observations. The observations were conducted in the family lounges or sitting rooms because they are the most frequently occupied spaces by family members as a gathering place.

In order to neutralize the stratification factors, globe temperature observations were made at a height of 1.0 to 1.3 m above the ground and at least 1.5 m away from walls or windows. Each observation lasted between 20 and 30 min to reach equilibrium with the indoor environment before the observations were taken, and observations were performed more than one time to obtain more accurate measurements.

2.3.2. Tools for Data Collection and Evaluation

This study tried to explore the relationship between acceptable indoor temperature limits and topographical variations within Mediterranean climates. The Center for the Built Environment (CBE) Thermal Comfort Tool-2020-Version: 2.5.6 [75] was provided as a computer tool for measuring the empirical variables involved in the calculation to evaluate PMV-PPD in this study. The following parameters were found in the process of each observation:

• GT: It stands for globe temperature (with a globe diameter of 40 mm); ASHRAE-55 states that the measurement must be taken at least one meter from the walls.
• ATi and RHi: The building’s interior air temperature and relative humidity, respectively, as measured by the CBE Thermal Comfort Tool’s Psychrometric (air temperature) method.
• Airspeed (As): The airspeed in the buildings was measured in meters per second using an anemometer.
• Clothing insulation was taken into consideration as 0.5 to 1.0 (clo) for summer and winter, respectively. These values reflect the typical indoor clothing insulation level in the summer and winter, according to ASHRAE Standards-55.
• Metabolic rate (Met) or the rate of activity: It is determined based on the observation area, and according to the site observation and ASHRAE-55, it was considered (1 Met) as a seated and quiet activity level. See

  Table 1. The tools and specific values for the required variables to be applied in the CBE Thermal Comfort Tool to evaluate PMV-PPD in this study.

  No.	The Variables	Observation Tool	Location of the Observation	Metabolic Rate (Met) (Seated and Quiet)	Clo Summer	Clo Winter
  	Environmental
  1	Indoor Globe Temperature (GT)	Glob thermometer EXTECH-H30 (globe diameter: 40 mm)	Family Lounge
  2	Indoor Air Temperature (ATi)	The weather station “HAMA” electronic set	Family Lounge
  3	Indoor Relative Humidity (RHi)	The weather station “HAMA” electronic set	Family Lounge
  4	Airspeed (Vs)	Anemometer model DA02	Family Lounge
  	Personal
  5	The activity level and Insulation level of clothing		Family Lounge	1.0	0.5	1.0

  .

It is important to mention that the probability sampling method was applied in this study. This method is commonly applied in quantitative research like the current study to produce results representative of the whole population. Stratified random sampling was utilized because the samples were divided into three main regions with the same number of residential buildings in each region randomly. The selection was random because access to the residential buildings was not always available and depended on the cooperation of the occupants. The selection of sample units from every region was based on the researcher’s judgment and the fundamental justification of their research [76]. To achieve credible statistical results, a sample of 30–50 case studies per region was sufficient for analyzing thermal comfort across different environments, for normality in sample distribution and a stable sample mean [76].

3. Findings

This study involved 300 sets of measurements, with 150 conducted in each season (summer and winter), covering 150 case study buildings. As previously mentioned, there are fifty measurement sets in each topographic region during the summer (July) and the same number of observations in winter (January). The goal was to evaluate the thermal comfort conditions inside these buildings based on their landform using the PMV-PPD index. The results showed different findings between summer and winter.

3.1. Findings from the Summer Data Collection

As previously stated, 150 sets of observations in each season were acquired to assess thermal comfort within the buildings in the study area. Therefore, thermal comfort conditions in case study buildings have been evaluated in each topographic region—coastal, hinterland, and mountainous—separately, based on fifty buildings in each of the regions within the city of Kyrenia. The evaluation has been made based on the PMV-PPD index in summer and winter. It is important to mention that the measured outside temperature in the coastal region during the observation periods was between 33 °C and 36.5 °C, and in the hinterlands, it was between 33.5 °C and 37 °C, while in the mountainous region, it was between 30.5 °C and 34 °C.

• Coastal area

Throughout summer (July), various observations indicated acceptable indoor thermal temperature limit conditions within buildings, depending on their location (coastal, hinterland, and mountainous) and the distinct microclimatic conditions of Kyrenia.

The data presented in

Table 2. The number of case studies in the neutral thermal state inside the buildings in the coastal area during the warm season.

No.	GT	ATi	Av	MRT	RHi	PMV	PPD	Sensation
1	26.4	27	0.1	25.8	63%	0.25	6%	Neutral
2	24.9	26.5	0.16	23.0	65%	−0.4	8%	Neutral
3	25.2	25	0.11	25.4	62%	−0.27	7%	Neutral
4	25.9	26.8	0.1	25.0	70%	0.13	5%	Neutral
5	26	27	0.17	24.6	60%	−0.12	5%	Neutral
6	25.6	26	0.08	25.3	63%	0.02	5%	Neutral
7	25.8	25.6	0.1	26.0	65%	0.02	5%	Neutral
8	27.1	26.7	0.08	27.4	58%	0.5	10%	Neutral
9	27.4	27.2	0.14	25.3	52%	0.49	10%	Neutral
10	27	28.7	0.14	24.9	64%	0.43	9%	Neutral
11	26.9	28	0.1	25.8	64%	0.46	9%	Neutral
12	26.6	26.3	0.11	26.9	58%	0.22	6%	Neutral
13	27.2	27	0.08	27.4	51%	0.49	10%	Neutral
14	24.9	24.4	0.04	25.2	50%	−0.45	9%	Neutral
15	25	25.8	0.08	24.3	59%	−0.23	6%	Neutral
16	26	27.5	0.1	24.5	63%	0.12	5%	Neutral
17	26.3	25.9	0.05	26.6	59%	0.19	6%	Neutral
18	25.5	24.7	0.06	23.0	53%	−0.21	6%	Neutral
19	26.3	28.8	0.18	22.7	68%	0.01	5%	Neutral
20	25.6	26.2	0.15	22.3	67%	−0.12	5%	Neutral
21	26.6	26	0.09	27.2	60%	0.32	7%	Neutral
22	27.3	26.9	0.06	22.1	50%	0.5	5%	Neutral
23	25.8	25.1	0.1	26.5	60%	−0.03	5%	Neutral
24	26.2	25.7	0.1	26.5	75%	0.25	6%	Neutral
25	25.4	24.8	0.07	25.9	57%	−0.19	6%	Neutral
26	26.7	26.1	0.06	27.1	61%	0.34	7%	Neutral
27	25.6	26.9	0.09	24.4	66%	0.04	5%	Neutral

indicate that twenty-seven residential buildings out of fifty witnessed neutral thermal conditions inside the buildings in the coastal area.

• Hinterland area

Fifty other case studies have been observed in terms of thermal comfort evaluation, and neutrality has been found in twenty-two buildings out of fifty. See

Table 3. The neutral thermal state inside the case study buildings in the hinterland area in the warm season.

No.	GT	ATi	Av	MRT	RHi	PMV	PPD	Sensation
1	26.2	27.5	0.16	24.5	60%	0.00	5%	Neutral
2	24.7	26.1	0.08	23.5	55%	−0.34	7%	Neutral
3	25.5	26.2	0.1	24.8	57%	−0.14	5%	Neutral
4	26.6	28.3	0.11	24.8	56%	0.24	6%	Neutral
5	26.5	28	0.13	24.8	64%	0.22	6%	Neutral
6	26.4	28.8	0.12	25.3	70%	0.29	7%	Neutral
7	26.6	28	0.07	25.5	55%	0.4	8%	Neutral
8	25.5	27.4	0.03	24.6	54%	0.12	5%	Neutral
9	24.8	25.9	0.04	24.2	56%	−0.25	6%	Neutral
10	25.5	25.4	0.05	25.6	58%	−0.1	5%	Neutral
11	25	24.6	0.09	25.4	64%	−0.26	6%	Neutral
12	26.1	25.4	0.04	26.5	62%	0.09	5%	Neutral
13	25.5	26	0.1	25.0	60%	−0.12	5%	Neutral
14	25.8	26.2	0.15	25.3	59%	−0.09	5%	Neutral
15	26	26.3	0.12	25.7	54%	0.06	5%	Neutral
16	25.2	25.7	0.06	24.8	66%	−0.1	5%	Neutral
17	25.3	24.9	0.09	25.7	60%	−0.18	6%	Neutral
18	26.3	26.2	0.08	26.4	58%	0.21	6%	Neutral
19	25.9	25.8	0.04	26.0	64%	0.11	5%	Neutral
20	25.6	25.2	0.06	25.9	56%	−0.11	5%	Neutral
21	26.9	26.5	0.07	27.2	61%	0.45	9%	Neutral
22	25.9	26.7	0.1	25.1	62%	0.06	5%	Neutral

.

• Mountainous area

The last fifty observations have been performed in the mountainous region, and the neutrality in thermal comfort was within thirty-three buildings out of fifty, which is the widest range within the three regions (coastal, hinterland, and mountainous). See

Table 4. The state of thermal neutrality in buildings located in the mountainous area during the summer.

No.	GT	ATi	Av	MRT	RHi	PMV	PPD	Sensation
1	27.4	27	0.12	27.8	50%	0.42	9%	Neutral
2	26.2	26	0.1	26.4	57%	0.1	5%	Neutral
3	26.3	28	0.16	25.7	52%	−0.04	5%	Neutral
4	25.9	26.2	0.06	25.7	46%	−0.02	5%	Neutral
5	26.4	26.5	0.05	26.3	50%	0.13	6%	Neutral
6	25.8	26.7	0.15	24.7	53%	−0.15	5%	Neutral
7	26.9	26.5	0.07	27.2	46%	0.31	7%	Neutral
8	26.1	26.4	0.09	25.8	51%	0.06	5%	Neutral
9	25.4	27	0.14	23.4	52%	−0.29	7%	Neutral
10	26.6	26.3	0.12	26.9	50%	0.12	5%	Neutral
11	25.6	25.2	0.08	25.9	51%	−0.15	5%	Neutral
12	27.2	27	0.1	27.4	44%	0.36	8%	Neutral
13	27	26.5	0.13	27.6	49%	0.24	6%	Neutral
14	24.4	25.8	0.09	23.1	56%	−0.49	10%	Neutral
15	26.3	25.5	0.11	27.1	45%	−0.01	5%	Neutral
16	24.9	24.8	0.07	25	43%	−0.46	9%	Neutral
17	26.8	26.8	0.06	26.8	55%	0.38	8%	Neutral
18	26.2	26.8	0.11	25.6	52%	0.04	5%	Neutral
19	26.3	25.9	0.09	26.7	40%	0.03	5%	Neutral
20	26	25.7	0.08	26.3	43%	−0.04	5%	Neutral
21	26.3	27	0.05	25.8	39%	0.1	5%	Neutral
22	26.6	27.7	0.15	25.2	44%	0.04	5%	Neutral
23	26.3	26.5	0.07	26.1	48%	0.13	5%	Neutral
24	26.1	25.7	0.06	26.4	47%	0.01	5%	Neutral
25	26.4	25.9	0.11	26.9	49%	0.06	5%	Neutral
26	25.1	24.1	0.08	26	47%	−0.41	8%	Neutral
27	26.8	28	0.12	24.7	45%	0.17	6%	Neutral
28	25.8	26.6	0.11	25	50%	−0.12	5%	Neutral
29	26.6	26.1	0.09	27.1	52%	0.24	6%	Neutral
30	26.3	25.9	0.13	26.8	56%	0.03	5%	Neutral
31	26.1	25.5	0.1	27.2	58%	0.16	6%	Neutral
32	27	26.3	0.08	27.6	38%	0.26	6%	Neutral
33	26.4	25.9	0.1	26.9	53%	0.14	5%	Neutral
34	26.8	28.9	0.11	24.6	58%	0.35	8%	Neutral
35	25.3	25.2	0.07	25.4	48%	−0.26	6%	Neutral
36	25.6	25.3	0.08	25.9	54%	−0.1	5%	Neutral
37	26.1	25.7	0.12	26.5	57%	−0.02	5%	Neutral

.

The results shown in Table 2, Table 3 and Table 4 indicate that the inner thermal neutrality varies across different regions. The result of the observations from different dwellings in different topographic regions within the study area in the hot season (July) demonstrates different percentages of thermal neutrality conditions inside the buildings. For example, the percentage of buildings with thermal neutrality in the coastal area was 54%, and in the hinterland, it was 44%, while in the mountainous region, it was 76%. Moreover, the range of acceptable indoor air temperature varied too. The acceptable indoor air temperature for attaining thermal neutrality in coastal dwellings ranged from 24.4 °C to 28.8 °C, whereas for hinterland buildings, it was between 24.6 °C and 28.8 °C. In the same context, mountainous regions need inside air temperatures ranging from 24.1 °C to 28.9 °C to achieve thermal neutrality. As a result, this required figuring out the maximum interior temperature required to create a thermally acceptable atmosphere in a variety of topographical locations with varying summertime microclimatic conditions. For instance, after obtaining neutral thermal conditions, the allowable air temperature range within residential buildings in the mountains showed a greater range. Additionally, the greatest temperature in this region (28.9 °C) might create a thermoneutral atmosphere. Furthermore, there were regional variations in the relative humidity, which has a major impact on thermal comfort conditions [77]. Relative humidity in thermal neutrality ranged from 50% to 75% in the coastal region, 54% to 70% in the hinterland, and 38% to 58% in the mountainous region, which was lower than in other areas. It is also critical to note that the orientation of the buildings has an impact on both the airspeed (Va) and the globe temperature (TG), which was directly impacted by the radiation and has a major impact on the PMV-PPD index results [77]. Nonetheless, the findings suggested that active systems may be adjusted to a greater temperature, which would reduce the energy needed to cool them. This suggests that the mountainous region is more adaptable than the others and offers a good variety of summertime thermoneutral climatic conditions (see Figure 5).

It is worth mentioning that the average predicted percentage of dissatisfied (PPD) inside buildings within acceptable indoor temperature ranges in summer was higher in the coastal area, where it was 6.6%, while in the hinterland and mountainous areas, it was 5.8%.

3.2. Findings from the Winter Observations

During the winter (January), another 150 observations inside 150 residential buildings were made with the same process of observation used in summer to evaluate thermal comfort conditions applying the PMV-PPD index. The temperature outside during the observation periods was between 10.5 °C and 17.5 °C in coastal areas and between 10 °C and 17.5 °C in the hinterlands, whereas it was between 8.5 °C and 15 °C in mountainous areas. However, the results demonstrated the following:

• Coastal area

The same fifty buildings selected in the summer were selected again in winter, and the observations were made in wintertime to evaluate thermal comfort conditions. The observations showed that thirty buildings were in the condition of indoor thermal neutrality out of fifty buildings, as seen in

Table 5. The state of neutral indoor thermal environment in buildings positioned in coastal areas during winter.

No.	GT	ATi	Av	MRT	RHi	PMV	PPD	Sensation
1	20.6	21.4	0	20.6	75%	−0.4	8%	Neutral
2	20.7	21.5	0.02	20.4	77%	−0.39	8%	Neutral
3	20.9	20.9	0	20.9	69%	−0.49	10%	Neutral
4	20.6	21.3	0	20.6	71%	−0.44	9%	Neutral
5	20.9	21.8	0	20.9	73%	−0.31	7%	Neutral
6	21.1	21.7	0.01	20.9	70%	−0.35	8%	Neutral
7	22	23	0	21.5	78%	0.06	5%	Neutral
8	20.2	21.1	0.01	20	78%	−0.5	10%	Neutral
9	20.6	20.9	0	20.6	73%	−0.5	10%	Neutral
10	21	21.6	0	21	61%	−0.41	9%	Neutral
11	21.6	22.3	0	21.6	76%	−0.12	5%	Neutral
12	20.9	21.4	0	20.9	72%	−0.38	8%	Neutral
13	21	21.9	0	21	70%	−0.3	7%	Neutral
14	21	21.6	0	21	68%	−0.37	8%	Neutral
15	21.6	22	0	21.6	67%	−0.24	6%	Neutral
16	20.5	20.9	0	20.5	75%	−0.49	10%	Neutral
17	21.8	22.3	0	21.8	79%	−0.08	5%	Neutral
18	20.3	21	0	20.3	76%	−0.49	10%	Neutral
19	20.7	20.9	0	20.7	71%	−0.5	10%	Neutral
20	22.2	22.6	0	22.2	78%	0.01	5%	Neutral
21	21.1	21.7	0	21.1	74%	−0.3	7%	Neutral
22	20.8	21.1	0	20.8	67%	−0.48	10%	Neutral
23	21.5	22	0	21.5	74%	−0.2	6%	Neutral
24	20.9	21.9	0	20.9	65%	−0.35	8%	Neutral
25	20.4	21.6	0	20.4	66%	−0.45	9%	Neutral
26	22.5	23.0	0	22.5	76%	0.10	5%	Neutral
27	20.4	21.8	0	20.4	69%	−0.4	8%	Neutral
28	21.7	22.5	0	21.7	76%	−0.08	5%	Neutral
29	21.3	22	0	21.3	70%	−0.25	6%	Neutral
30	21	21.4	0	21	72%	−0.37	8%	Neutral

.

• Hinterland area

Table 6. Thermal neutrality inside buildings in the hinterland area in winter.

No.	GT	ATi	Av	MRT	RHi	PMV	PPD	Sensation
1	21.9	22.6	0	21.9	73%	−0.06	5%	Neutral
2	20.9	21.7	0	20.9	62%	−0.4	8%	Neutral
3	20.7	21	0	20.7	68%	−0.5	10%	Neutral
4	21.1	21.5	0	21.1	67%	−0.38	8%	Neutral
5	21.4	22.1	0	21.4	70%	−0.22	6%	Neutral
6	21	21.6	0	21	64%	−0.39	8%	Neutral
7	21.3	21.9	0	21.3	68%	−0.28	7%	Neutral
8	20.7	21.3	0	20.7	65%	−0.47	10%	Neutral
9	21.2	21.7	0	21.2	62%	−0.37	8%	Neutral
10	21.1	21.4	0	21.1	70%	−0.38	8%	Neutral
11	21.5	22.1	0	21.5	71%	−0.2	6%	Neutral
12	21	21.8	0	21	68%	−0.33	7%	Neutral
13	20.8	21.5	0	20.8	62%	−0.45	9%	Neutral
14	21.1	21.6	0	21.1	63%	−0.39	8%	Neutral
15	21.2	21.4	0	21.2	69%	−0.37	8%	Neutral
16	20.6	21.5	0	20.6	62%	−0.47	10%	Neutral
17	21.9	22.5	0	21.9	72%	−0.08	5%	Neutral
18	20.9	21.5	0	20.9	66%	−0.41	8%	Neutral
19	20.5	21.5	0	20.5	64%	−0.47	10%	Neutral
20	21	21.3	0	21	67%	−0.41	8%	Neutral
21	21.4	21.8	0	21.4	64%	−0.31	7%	Neutral
22	20.7	21.3	0	20.7	62%	−0.49	10%	Neutral
23	21.6	22.1	0	21.6	71%	−0.19	6%	Neutral
24	20.5	21.5	0	20.5	68%	−0.44	9%	Neutral
25	21.1	21.8	0	21.1	66%	−0.33	7%	Neutral
26	21	21.4	0	21	65%	−0.42	9%	Neutral
27	21.3	22	0	21.3	63%	−0.3	7%	Neutral
28	21.8	22.3	0	21.8	69%	−0.15	5%	Neutral
29	20.8	21.5	0	20.8	66%	−0.42	9%	Neutral

demonstrates thermal comfort conditions in the selected case study buildings in the hinterlands in winter. The results identified neutral thermal conditions inside twenty-nine buildings out of fifty buildings in this area.

• Mountainous area

A thermal comfort evaluation was conducted in the mountainous region, and only twenty-three residential buildings out of the selected fifty dwellings arrived at a neutral thermal condition during the winter (January). See

Table 7. Indoor thermoneutral temperature ranges inside buildings in the mountainous area in winter.

No.	GT	ATi	Av	MRT	RHi	PMV	PPD	Sensation
1	21	21.8	0	21	63%	−0.37	8%	Neutral
2	21.3	22	0	21.3	65%	−0.28	7%	Neutral
3	20.7	21.6	0	20.7	58%	−0.47	8%	Neutral
4	20.9	21.7	0	20.9	62%	−0.4	8%	Neutral
5	21.4	21.9	0	21.4	64%	−0.3	7%	Neutral
6	20.5	21.4	0	20.5	63%	−0.49	10%	Neutral
7	20.9	21.2	0	20.9	61%	−0.49	10%	Neutral
8	20.8	21.5	0	20.8	62%	−0.45	9%	Neutral
9	21.6	22	0	21.6	65%	−0.25	6%	Neutral
10	20.8	21.6	0	20.8	64%	−0.42	9%	Neutral
11	21.4	21.9	0	21.4	63%	−0.3	7%	Neutral
12	21.6	22.2	0	21.6	67%	−0.2	6%	Neutral
13	21.5	21.7	0	21.5	62%	−0.33	7%	Neutral
14	21.8	22.1	0	21.8	66%	−0.2	6%	Neutral
15	21.2	21.8	0	21.2	65%	−0.33	7%	Neutral
16	20.9	21.5	0	20.9	64%	−0.42	9%	Neutral
17	21	21.4	0	21	63%	−0.43	9%	Neutral
18	21.9	22.2	0	21.9	66%	−0.17	6%	Neutral
19	21.6	22.3	0	21.6	67%	−0.19	6%	Neutral
20	20.9	21.8	0	20.9	63%	−0.38	8%	Neutral
21	21.1	21.7	0	21.1	64%	−0.36	8%	Neutral
22	21.1	21.6	0	21.1	61%	−0.4	8%	Neutral
23	21.5	22	0	21.5	65%	−0.26	6%	Neutral

.

The results demonstrated that the highest percentage of thermal neutrality inside the buildings was in the coastal area, at 60%, and the percentage was 58% for the hinterlands, while it was only 46% in the mountainous region. Additionally, the results showed varying ranges of inner air temperature for reaching thermally neutral conditions inside the buildings throughout the winter (January), as shown in Table 5, Table 6 and Table 7. It is important to mention that the interior accepted air temperature range for arriving at thermal neutrality for the residential buildings in the coastal area was between 20.2 and 23.0 degrees Celsius. In the same context, the same type of buildings in the hinterland had temperatures between 21 and 22.6 degrees Celsius. Additionally, the acceptable indoor temperature ranged from 21.2 °C to 22.3 °C in dwellings located in mountainous areas.

In the three research regions, the relative humidity was determined in each region under the neutral thermality condition inside the buildings in the various topography and microclimatic circumstances, showing varying ranges. The coastline region had the largest range of relative humidity, ranging from 61% to 79%, while the hinterland regions had a lesser range, ranging from 62% to 73%. Nonetheless, mountainous areas had the lowest humidity range within the thermal neutrality of the buildings, ranging from 58% to 67%.

The results showed that, in the coastal location, the minimum air temperature needed to reach a thermally neutral level within the building during the winter was 20.2 °C. In order to maintain a better range of acceptable thermal temperature conditions in the winter, the minimum needed air temperature for the heating active systems in each topographic zone was determined. See Figure 6.

However, the average PPDs within buildings at accepted interior temperature limits throughout winter were close to each other in all the regions. In both coastal and hinterland regions, PPD was 7.8%, while it was slightly lower, 7.6%, in the mountainous area.

The statistical analysis of mean differences employed a one-way ANOVA test to examine statistically significant differences among the means of three or more independent groups, referred to as the null hypothesis, during summer and winter. The findings demonstrated that the wintertime results across the three groups in the three locations (coastal, hinterland, and mountainous) indicate an f-ratio value of 0.3682. The p-value is 0.693207. The result reveals that there is no significance at p < 0.05. This suggests that there are no significant statistical differences between the groups. In the same context, in the summertime, the f-ratio value is 0.11334. The p-value is 0.892989. This finding is not significant at p < 0.05. Once more, the findings indicate that there are no statistically significant differences between the groups throughout the summer.

However, the practical utility of data is sometimes determined by factors other than statistical significance. The data nevertheless offer crucial contextual insights about temperature behavior in different places, even if the differences are not statistically significant. Furthermore, the results offer a comprehensive understanding of the range of required air temperature to achieve a neutral thermal condition in each region of the study area.

4. Discussion

The outcomes of the observations and evaluations for one hundred fifty residential buildings in different regions with different elevations above sea level in Kyrenia demonstrate different results. See

Table 8. The effect of topography on acceptable temperature, relative humidity, and predicted percentage of dissatisfied inside the buildings in the study area.

No.	Region	Max. Neutral thermal Temperature (°C)	Min. Neutral Thermal Temperature (°C)	Percentage of Indoor Thermal Neutrality Within Total Number of Buildings	Relative Humidity Ranges Inside the Buildings	PPD
	Summer
1	Coastal	24.4	28.8	54%	50% to 75%	6.6%
2	Hinterland	24.6	28.8	44%	54% to 70%	5.8%
3	Mountainous	24.1	28.9	76%	38% to 58%	5.8%
	Winter
1	Coastal	20.9	23	60%	61% to 79%	7.8%
2	Hinterland	21	22.6	58%	62% to 73%	7.8%
3	Mountainous	21.2	22.3	46%	58% to 67%	7.6%

.

As shown in Table 8, the maximum acceptable indoor air temperature in summer for maintaining thermal neutrality was 28.9 °C, and the lowest air temperature was 24.1 °C, and they were within the mountainous region. This indicates more flexibility in maintaining thermal comfort inside the buildings with less energy consumption of active cooling systems. Due to the height of the region—altitude [78], which is between 150 m and 300 m above sea level—a lower indoor relative humidity range in neutral thermal conditions was observed, and it was between 38% and 58%. Moreover, the highest percentage of buildings with thermally neutral indoor conditions was in the mountainous region too, and it was 76%. It is important to mention that the lower average PPD was in mountainous and hinterland regions, at 5.8%, while the highest was in the coastal area, at 6.6%. The coastal area demonstrated narrower limits of acceptable air temperature for achieving thermal neutrality, between 24.4 and 28.8 °C, while the narrowest range was in the hinterland area (24.6 °C to 28.8 °C). Despite the higher relative humidity inside the coastal region buildings, which was reflected in the PPD, which was the highest (6.6%), the percentage of the buildings that met thermal neutrality was higher than in hinterland region buildings. This is because the range of the acceptable indoor air temperature for reaching thermal neutrality was wider in the coastal area (24.4 °C to 28.8 °C) than in the hinterland region (24.6 °C to 28.8 °C).

Practically, the energy usage in buildings will increase as the minimum temperature required for thermal neutrality rises. Empirically, the mountainous region will use less energy for cooling due to its broader acceptable indoor temperature range (24.1 °C to 28.9 °C) and lower indoor humidity (38–58%). Less active cooling is required since 76% of the building has reached thermal neutrality. The coastline and hinterland areas, on the other hand, will need more energy for precise cooling to ensure comfort because their temperature ranges are smaller for thermal neutrality. As a result, during the hot season, the mountainous area will use less energy for cooling than other areas.

In winter, the upper and lower air temperatures required to maintain thermal neutrality inside the buildings were 23 °C and 20.9 °C, respectively, in the coastal area with the lowest elevation above sea level (2.5 m to 35 m). Therefore, the highest relative humidity inside a building with neutral thermal conditions was registered in this region, and it was 75%. Moreover, 60% of the selected buildings were within the condition of thermal neutrality, and this was the highest percentage when compared with the hinterland region (58%) and the mountainous region (46%). The acceptable interior air temperature for reaching thermal neutrality in the hinterland region was limited between 21 °C and 22.6 °C, and for the mountainous region, it was between 21.2 °C and 22.3 °C. This demonstrates that the higher energy consumed in mountainous areas in the winter for heating to reach thermal comfort conditions is based on the minimum air temperature degree required to arrive at thermal neutrality.

The coastal zone requires less heating energy to maintain thermal comfort due to the higher relative humidity and lower temperature requirements (high: 23 °C, low: 20.9 °C). However, buildings will require more energy to achieve and maintain these conditions during the cold winter months in the mountainous zone, where the minimum allowable temperature range is much lower (21.2 °C to 22.3 °C). The cooler outside temperatures in the mountainous and hinterland areas are the main cause of the increased need for heating, which raises the energy costs of heating systems to maintain inside thermal neutrality and make up for the temperature differential. As a result, these areas would require more energy and incur higher operating costs than the coastal area.

Several studies in Mediterranean climates about the indoor air temperature range to implement thermal conditions in the buildings have been reviewed and found quite in line with the results of the current study. A study on residential buildings in Cyprus found that the upper and lower air temperatures for achieving thermal neutrality in summer were between 28.5 °C and 31.5 °C [79]. In another study, the neutral temperature in the hot Mediterranean climate (Csa) was found to be between 20 °C and 26 °C [80]. In an office building in the Mediterranean climate of Izmir, Turkey, the neutral thermal temperature was 19.4 °C for summer and 22.4 °C for winter [81].

Identifying the upper and lower air temperatures for arriving at thermal neutrality inside a building, in addition to the other indicators, is a good guideline for architects and heating and cooling specialists. It can help them make more precise decisions to prevent excessive energy consumption to reduce thermal discomfort within buildings and enhance productivity, indoor environments, and the general health of inhabitants.

Furthermore, the current study’s outcomes contain several empirical suggestions for regulating and controlling interior temperatures in different topographic regions in the Mediterranean climates of Cyprus. Although there are small differences in the indoor accepted temperature among the different regions, the result helps to create energy-efficient building designs and improve thermal comfort. The main purpose of this research is to create more sustainable, energy-efficient, and thermally comfortable inner spaces in residential buildings.

5. Conclusions

This study aimed to develop a more accurate thermal comfort evaluation for regions with different elevations above sea level in the Mediterranean climate of Kyrenia, Northern Cyprus. A case study technique was employed to obtain the results, and one hundred fifty residences were selected from three primary regions of the study area: coastal, hinterland, and mountainous, each with varying altitudes above sea level, as illustrated in Figure 3. The chosen buildings utilized a mixed-mode system, with one heating or cooling system operational during the observation period. The PMV-PPD index has been used to assess thermal comfort conditions within buildings in the summer (July) and winter (January).

To achieve this, office work using software (CBE Thermal Comfort Tool-2020) and direct observations at the site were carried out. The goal of this study was to determine the highest and lowest indoor temperatures in buildings with neutral thermal conditions.

The findings indicated that the maximum indoor air temperatures over the summer and the winter were 28.9 °C and 20.9 °C, respectively. These temperature ranges reflect the total inner temperature limitations needed to provide neutral thermal conditions in the Northern Cyprus region of Kyrenia.

Despite the slight differences in indoor acceptable temperature, the outcomes demonstrated that there is a significant effect of the topography and the elevation above sea level on the indoor acceptable thermal temperature ranges to arrive at thermal neutrality. For instance, the mountainous region demonstrated the best topographic area in terms of thermal comfort tolerance within neutral thermal conditions and showed a wider range of acceptable indoor air temperatures in summer, which was between 28.9 °C and 24.1 °C. However, in terms of energy efficiency, the mountainous region in summer was the best with higher air temperature tolerance, and the hinterland and coastal regions were next because the upper temperatures of coastal and hinterland areas were the same. In winter, the coastal area was the best in terms of thermal neutrality achievement through the broader range of temperatures and had a lower indoor acceptable temperature for achieving thermal neutrality, which consumes less energy when active systems are used. Also, a higher percentage of thermal neutrality has been found in this region, with 60% of the total selected dwellings. However, the next was the hinterland region, and the mountainous region showed lower tolerance for thermal neutrality inside the buildings and a higher requirement for heating to reach thermal comfort. Nevertheless, the lowest PPD was found in the mountainous region because of its lower range of relative humidity inside the buildings compared with other regions, as seen in Table 8.

These findings apply to dwellings in the research region and offer novel criteria for active heating and cooling system design. Significantly, understanding interior accepted temperature limits for reaching thermal comfort during the design stage helps engineers and architects create spaces that maximize comfort, reduce energy consumption, and align with the needs and preferences of building occupants. This is accomplished by modifying the active cooling and heating systems within the precise ranges of indoor acceptable temperatures, which usually vary according to the season, the topography, or the elevation above sea level. Extra empirical studies are required to evaluate the amount of reduction in energy consumption for heating and cooling during the application of the findings of the current study.

However, it is worth mentioning that the suggested guideline of this study may vary for other typologies of buildings like commercial, public, and industrial buildings because of the design, building materials, and even HVAC systems. Moreover, the impact of the climate in different climatic zones can be another challenge that limits the results of the current study, which needs to be addressed in future studies as well. Therefore, future studies should focus on examining these types of buildings. In the same context, shading or solar radiation effects can greatly reduce active system demands and improve buildings’ energy efficiency while maintaining residents’ thermal comfort [82,83]. Therefore, future studies should monitor globe temperature (GT), which combines the effects of solar radiation and air temperature [77], within buildings related to various topographic regions. This will help us understand the impact of shading and solar radiation on thermal neutrality evaluation by comparing the findings with those of the current study. On the other hand, finding the relationship between mean radiant temperature (MRT) and the air temperature can give a good indicator of the effect of shading or solar radiation on thermal comfort conditions inside buildings with respect to the orientation of the buildings. Moreover, studying the occupants’ perception of thermal comfort along with the PMV-PPD approach will help in obtaining more realistic outcomes by investigating thermal comfort objectively and subjectively and comparing the results.