**3. Results and Discussion**

#### *3.1. Indoor Environment Monitoring*

Measurements of speed were taken three times during the day at short intervals, with the purpose of evaluating the building's natural airflow and ventilation. The wind direction was recorded using smoke tracers located at the points indicated in Figure 6, simultaneously. The experiments, their conditions, and the locations of the sensors for wind speed data collection are described as follows.

Experiment 1 involved measuring data at doors A and C, while doors A, B, and C remained open, and all other doors were closed. This experiment revealed that during the 15-min sampling period in the morning, the wind at door A originated from the west, while, at door C, it changed direction to the east. The wind speed at door A exhibited significant strength, averaging 1.35 m/s, whereas, at door C, it was approximately 0.81 m/s (Figures 7 and 8).

**Figure 7.** Short-term variation in wind speed monitored during the morning.

Door A Door C

**Figure 8.** Smoke tracer for determination of wind direction during the morning.

During the second experiment, data were recorded in the afternoon for a sampling period of 15 min. The test involved closing all doors except for door "A", and measurements were taken at door "A" and in the central courtyard. The recordings revealed that the wind in the central courtyard had an upward direction, while, at door "A", the wind had a west–east direction. Additionally, in this experiment, it was found that the wind at door "A" had an average velocity of 0.88 m/s, with a recorded maximum of 2.20 m/s during the sampling period. The wind speed in the central courtyard was much lower, with an average of 0.48 m/s (Figures 9 and 10).

**Figure 9.** Short-term variation in wind speed monitored during the afternoon.

Door A

Door C

**Figure 10.** Smoke tracer for determination of wind direction during the afternoon.

Experiment 3 was conducted at night for 10 min to evaluate the natural ventilation of the building. The experimental conditions were the same as in experiment 1, with measurements taken at door A, the central courtyard, and door C. The wind direction was found to be west–east at both door A and door C, while an upward direction was observed in the central courtyard. The average wind speed at door A was recorded as 0.91 m/s,

while, at door C, it was measured to be 0.80 m/s., while the average speed in the central courtyard was 0.41 m/s (Figures 11 and 12). These findings provide insight pertaining to the natural airflow and ventilation within the building during nighttime.

**Figure 11.** Short-term variation in wind speed monitored during the night.

Door C

**Figure 12.** Smoke tracer used to determine wind direction during the night.

The experimental tests (2 and 3) show that the predominant local wind comes from the west–east direction, and this wind stream can be regarded as the main source of natural ventilation within the house. However, according to test 1, the predominant local wind takes two directions, west to east (door A) and east to west (door C), during the morning. The courtyard functions as an outlet for air circulation, while the windows and doors serve as inlet openings for fresh air intake; the smoke tracers placed in the central courtyard showed that the natural ventilation during the morning, afternoon, and night was upward, producing a chimney effect. Nevertheless, it is noteworthy that the main room of the building, where a wind speed recorder was placed despite being oriented in the predominant wind direction, recorded an average speed of 0.39 m/s, which can be considered imperceptible. This observation is supported by the smoke tracer images placed in the main room (Figure 13).

**Figure 13.** Smoke tracer for determination of wind direction in the main hall.

The air temperature profiles shown in Figure 14 demonstrate that the outdoor temperature exhibited a diurnal variation of 6.96 ◦C (i.e., ranging from 8.80 ◦C to 15.16 ◦C), while the temperature recorded in the main room fluctuated between 15.11 ◦C and 17.05 ◦C, displaying a diurnal variation of 1.94 ◦C over the same time period. The central courtyard had an average temperature of 14.92 ◦C, and the temperature inside the building was higher than the outdoor temperature, whereas the outdoor temperature was 1.67 ◦C lower than that of the rear vestibule. It is evident that the temperature variations in the mezzanine room and bedroom 7 coincided throughout the monitoring period. The mezzanine room was approximately 0.23 ◦C warmer than bedroom 7, while the main room was 1.26 ◦C hotter than bedroom 7 during the day. At night, bedroom 7 was slightly cooler than the main room, with a difference of 0.30 ◦C.

The relative humidity (RH) levels in the central courtyard, as depicted in Figure 15, exhibited the most fluctuation among the interior values (i.e., varying from 59.03% to 85.43%). The relative humidity in bedroom 7 was the most stable (i.e., varying by only 1.93%, from 67.23% to 69.15%), while the highest value (around 88.86%) was observed in the rear vestibule during the monitoring period. It is important to note that while the temperature in bedroom 7 was lower than in the main room during nighttime, the former exhibited lower relative humidity values, indicating a drier environment compared to the latter. Based on the monitoring results, bedroom 7 was the coolest place in the house. This phenomenon can be attributed to the fact that bedroom 7 was enclosed by three solid walls and had only one connection to the exterior (central courtyard) through a door. As a result, natural ventilation in this area was restricted. However, the room benefitted from effective shading, reducing the influence of the outdoor air temperature and solar radiation.

**Figure 14.** Variation in air temperature at diverse monitoring points.

The air temperature in the rear vestibule was the coldest in the house. Moreover, this space was the most humid, despite having good natural ventilation. This behavior can be attributed to the fact that this environment is located at a lower level with respect to the street level, and its enclosing structure is composed of wooden partitioning. According to the monitoring results, the relative humidity in the mezzanine room was the most constant among all the rooms in the house. However, it was cooler than the main room.

The temperature profiles of the internal wall surfaces in bedroom 7 are presented in Figure 16. The results show that the west wall surface has the largest diurnal variation of 1.4 ◦C (i.e., from 17.00 ◦C to 18.40 ◦C), while the east wall surface has the lowest

variation at night (i.e., 0.10 ◦C from 15.30 ◦C to 15.40 ◦C). The north wall surface maintains a stable temperature at 15.50 ◦C during the night. The internal south wall surface records the lowest average temperature during the night at 14.92 ◦C, while the external surface records 15.00 ◦C, with a variation of 0.08 ◦C. The temperature of the internal wall surfaces in bedroom 7 is higher than the external temperature; this can be attributed to the thermal insulation and thermal mass properties of the walls, which contribute to the observed effects.

**Figure 16.** Variation in surface temperature of envelopes in bedroom 7.

#### *3.2. Thermal Performance Simulation*

In order to identify whether there were environmental improvements in the case study, a thermodynamic performance analysis was performed. Firstly, a model of the current state of the building was obtained through the EnergyPlus/Open Studio graphic interface [22]. The data were collected through planimetric measurements of the building, as there were no existing records due to its age. In the model, all thermophysical properties of the building's envelope were defined (Table 4). The values of the opaque envelope were taken in situ using the Testo 635 Surface Thermometer tool, and for the transparent envelope (and other materials that could not be measured), the values were taken from the Ecuadorian Construction Standard [23]. Additionally, usage schedules and profiles were defined for a home with an average occupancy of three people (current number of occupants), an internal load with lighting power of 11.62 W/m2, and electrical equipment of 48 W/m2. The analysis was conducted in the absence of an air conditioning system, which is typical for residential buildings in the studied area. Consequently, the behavior of the building under external climatic conditions was the focus of the study. Finally, we inputted meteorological data for an entire year from the weather station located 3 km from the building (identified as DX300 HOBO). EnergyPlus was then used for energy calculations and Radiance was used to simulate the thermodynamic performance. To ensure the reliability of the simulation results, the model was validated (Figure 17) through the calibration of the model with a comparison process between experimental data taken during the monitoring of the interior environment of the living room and the simulation results.


#### **Table 4.** Thermophysical parameters of the simulated building.

**Figure 17.** Constructed simulation model and model validation procedure.
