# Ecological and Energy Footprint of Traditional Stone and Clay Habitats versus Modern Cement Concrete Habitats: Carbon Balance and Comfort of Habitats

Alexis DZOKOM¹, ², Ezechiel KODJI³, Roger Djouldé DARMAN⁴

¹Sahel Nature Consulting

²Department of Geography, Faculty of Arts and Letters and Social Sciences, University of Maroua, Cameroon

³Department of Environmental Sciences, National Advanced School of Engineering, University of Maroua, Cameroon

⁴Department of Agriculture Animal Husbandry and By-Products, Faculty of Sciences, University of Garoua, Cameroon

## Abstract

In the context of energy transition and climate issues, the comparison between traditional stone and clay habitats and modern cement concrete constructions appears essential to rethink our construction methods. This article presents a comparative study based on life cycle analysis (LCA) according to ISO 14040 and 14044 standards, in situ measurements and thermal simulations, in order to assess the carbon footprint, energy consumption and comfort of the interiors in these two construction typologies. Modern materials are generally denser (2033.33 ± 251.66 kg/m³) than traditional materials (1566.67 ± 950.44 kg/m³), but the latter have a greater dispersion (higher standard deviation). Traditional materials show a greater variability in higher average specific heat capacity (1366.67 ± 814.45 J/kg·K), especially due to wood which has a much higher heat capacity than others. Modern materials have a more homogeneous and slightly higher thermal conductivity (1.45 ± 0.26 W/m·K) than traditional materials (1.16 ± 1.22 W/m·K), which may influence their ability to thermally insulate a building. The graphical analysis of CO₂ emissions, indoor temperature variation and energy costs highlights the environmental and thermal advantages of traditional constructions, while discussing their limits of adaptation to contemporary requirements. Our results open the way to hybrid strategies that could reconcile heritage, sustainability and comfort.

**Keywords:** ecological footprint, carbon footprint, life cycle analysis (LCA), traditional versus modern housing, environmental impact of materials.

## 1. Introduction

Construction choices in arid zones are decisive for the ecological and energy footprint of habitats, influencing both greenhouse gas (GHG) emissions and the thermal comfort of occupants. In the mountainous Sahelian regions of Cameroon, the opposition between traditional stone and clay habitats and modern cement concrete constructions raises questions about their sustainability and environmental impact. Traditional habitats, made from local and minimally processed materials, are generally recognized for their low carbon footprint and their ability to adapt to extreme climatic constraints (Houben & Guillaud, 1994). Conversely, concrete habitats, although perceived as more resistant and modern,

generate a significant carbon footprint due to the high energy intensity of the cement production process (Scrivener et al., 2018). The scientific literature highlights the advantages of natural materials in hot and dry climates. According to Bouchair (2004), raw earth structures have a high thermal inertia that helps regulate temperature differences between day and night, thus reducing the need for air conditioning. In addition, clay and stone constructions come from a more virtuous life cycle, integrating biodegradable or reusable materials, unlike concrete, the manufacture of which contributes to around 8% of global CO₂ emissions (IEA, 2021). Reducing the ecological and energy footprint of buildings is now at the heart of environmental and societal concerns.
Indeed, the construction sector represents a significant share of CO₂ emissions (Dzokom et al., 2024a; Smith et al., 2020), mainly linked to the production of materials and energy consumption during the operation of buildings. At the same time, the comfort of residents, both thermal and acoustic, remains an essential criterion for guaranteeing the quality of life in homes. In addition, the thermal comfort of homes is a crucial issue in the Sahelian zone, where extreme temperatures directly affect the quality of life of populations. Recent studies show that modern concrete buildings, due to their high thermal conductivity and low heat dissipation capacity, can generate more pronounced thermal discomfort conditions compared to traditional housing (Adam & Jones, 2018). It therefore appears essential to comparatively assess the environmental and energy performances of these two types of habitats in order to guide construction practices towards more sustainable solutions adapted to local climatic realities. This study proposes to analyze the ecological and energy footprint of traditional stone and clay habitats compared to cement concrete constructions through a detailed carbon footprint and an assessment of thermal comfort. The objective is to provide scientific elements to improve construction strategies in the Sahelian environment, by reconciling environmental imperatives and the well-being of local populations.

## 2. Materials and Methods

### 2.1 Selection of Case Studies

The selection criteria included age, orientation, spatial configuration and availability of technical and energy data. Two sets of buildings were selected in geographical areas with a temperate climate:

* Traditional Habitats: Stone and clay constructions, located in rural areas where the use of local materials is predominant.

* Modern Habitats: Recent cement concrete buildings, located on the outskirts of towns, built to industrial standards.

### 2.2 Data Collection and In Situ Measurements

Technical data on materials (density, thermal capacity, conductivity) were collected from specialized databases (ADEME, Base Carbone) and recent publications. Measurement campaigns were conducted over a 12-month period to collect:

* Temperature and Humidity: Sensors (accuracy ± 0.3°C) installed in different rooms.

* Heat Flow and Solar Irradiation: Integrated data loggers.

* Comfort Surveys: Questionnaires for occupants regarding thermal and acoustic comfort.

Here is a structured table of data from the 12-month measurement campaigns:

<table><caption>**Table 1:** Methodologies used during the 12-month measurement campaigns</caption><thead><tr><td>Measurement methods</td><td>Parameters</td><td>Recording frequency</td><td>Instrument accuracy</td></tr></thead><tbody><tr><td>Sensors placed in different rooms</td><td>Indoor temperature</td><td>Continuous measurements (every 10 min)</td><td>±0.3°C</td></tr><tr><td>Humidity sensors associated with temperature sensors</td><td>Relative humidity</td><td>Continuous measurements (every 10 min)</td><td>±2% RH</td></tr><tr><td>Heat flow recorders fixed on the walls</td><td>Heat flux</td><td>Recording every 15 min</td><td>±5%</td></tr><tr><td>Pyranometer or solar irradiation sensor on the roof</td><td>Solar irradiation</td><td>Hourly measurements</td><td>±10 W/m²</td></tr><tr><td>Questionnaires submitted to occupants (thermal and acoustic comfort)</td><td>Comfort surveys</td><td>Once a month</td><td>Qualitative data</td></tr></tbody></table>
## 2.3 Life Cycle Assessment (LCA) and Carbon Footprint Calculation

LCA is performed according to ISO 14040 and 14044 standards. The phases assessed include:

<table><caption>**Table 2: Life Cycle Assessment Methodologies**</caption><thead><tr><td>Methods of Analysis</td><td>Life Cycle Phase</td><td>Data Collected / Indicators</td></tr></thead><tbody><tr><td>- Life cycle analysis (LCA) of materials (ISO 14040)<br/>- Carbon footprint of materials<br/>- Evaluation of embodied energy</td><td>Production and Extraction of Materials</td><td>- CO<sub>2</sub> emissions/kg of material (80-120 kg CO<sub>2</sub>/tonne for stone/clay, 450 kg CO<sub>2</sub>/tonne for cement)<br/>- Extraction energy consumption (MJ/tonne)<br/>- Impact on natural resources (deforestation, mineral extraction)</td></tr><tr><td>- Inventory of material and energy flows (LCA inventory method)<br/>- Calculation of transport emissions (distances, type of fuel)</td><td>Construction & Transportation</td><td>- Energy consumption for implementation (MJ/m<sup>2</sup>)<br/>- CO<sub>2</sub> emissions linked to transport (kg CO<sub>2</sub>/km)<br/>- Volume and origin of materials</td></tr><tr><td>- On-site energy monitoring (temperature, humidity, electricity consumption sensors)<br/>- Thermal and acoustic comfort studies (occupant surveys)</td><td>Exploitation (Energy Use and Performance)</td><td>- Average indoor temperature (°C)<br/>- Heating/air conditioning requirements (kWh/m<sup>2</sup>/year)<br/>- Thermal comfort factors (ventilation, insulation)</td></tr><tr><td>- Analysis of end-of-life scenarios (demolition, reuse, recycling)<br/>- Evaluation of waste flows and reuse potential</td><td>End of Life (Demolition and Recycling)</td><td>- % of reusable or recyclable materials<br/>- CO<sub>2</sub> emissions from demolition (kg CO<sub>2</sub>/m<sup>2</sup>)<br/>- Cost and environmental impact of waste treatment</td></tr></tbody></table>

These life cycle analysis methods applied to traditional habitats (stone/clay) and modern habitats (cement concrete) in the arid mountainous Sahelian zone of Cameroon

integrates specific physical characteristics of each material. The Climate scenarios induce simulations of real and extreme conditions and the validation highlights the comparisons with in situ data to adjust the model parameters.

## 2.4 Thermal Modeling and Simulation

The simulations were carried out using EnergyPlus software. The modeling

<table><caption>**Table 3: Comparison integrating in situ measurements and simulation results on heating consumption reduction and end-of-life scenarios of materials.**</caption><thead><tr><td>Criterion</td><td>In situ measurements</td><td>Simulations</td></tr></thead><tbody><tr><td>Reduction of heating consumption</td><td>Observed reduction of 18-22% for stone/clay buildings</td><td>Confirmation of an average reduction of 20%</td></tr><tr><td>Stable indoor temperature</td><td>Limited variations thanks to the high thermal inertia of natural materials</td><td>Simulation showing a thermal shift beneficial for comfort</td></tr><tr><td>Humidity and hygrometric regulation</td><td>Better regulation observed with clay</td><td>Modeling confirming a capacity for absorption and restitution of humidity</td></tr><tr><td>End of life and recyclability</td><td>Raw stones and earth reused on site, little waste</td><td>Simulation confirming a reduction in the carbon footprint due to reuse</td></tr><tr><td>End of life CO<sub>2</sub> emissions</td><td>Low for stone and clay, higher for concrete</td><td>Estimation of a carbon footprint up to 50% lower for natural materials</td></tr></tbody></table>

## 2.5 Graphical and Statistical Analyses
The data were processed with SPSS and presented in the form of graphs. Among the analyses carried out: the comparison of cumulative CO₂ emissions (kg/m²) over the life cycle for the two typologies; the illustration of the variation in indoor temperature over a 24-hour period for a traditional habitat vs. a modern habitat; the comparative diagram of annual energy costs related to heating and air conditioning. Statistical analyses (ANOVA, correlation

tests) made it possible to identify the significance of the differences observed.

### 3. Results

The analysis of field surveys conducted in the arid Sahelian mountainous areas of Mokolo, Mora and Kaélé made it possible to establish a comparative table of the selection criteria for traditional and modern habitats:

<table><caption>**Table 4:** Selection criteria between traditional and modern habitats</caption><thead><tr><th>Selection criteria</th><th>Traditional Habitats (Mokolo)</th><th>Modern Habitats (Mokolo)</th><th>Traditional Habitats (Mora)</th><th>Modern Habitats (Mora)</th><th>Traditional Habitats (Kaélé)</th><th>Modern Habitats (Kaélé)</th></tr></thead><tbody><tr><th>Age of infrastructure</th><td>Very old (&gt;50 years)</td><td>Recent (10-30 years)</td><td>Old (&gt;40 years)</td><td>Recent (5-20 years)</td><td>Old (&gt;30 years)</td><td>Mixed (old and recent)</td></tr><tr><th>Orientation</th><td>Adapted to prevailing winds (North-South)</td><td>Random, depending on the road</td><td>Aligned with local winds (East-West)</td><td>Depending on infrastructure</td><td>Aligned with the main axes</td><td>Depends on access routes</td></tr><tr><th>Spatial configuration</th><td>Dispersed, in family concessions</td><td>Grouped, demarcated plots</td><td>Grouped in small village centers</td><td>Dense urban housing</td><td>Semi-dispersed, following natural reliefs</td><td>Linear habitat along roads</td></tr><tr><th>Availability of technical data</th><td>Low (empirical construction, oral transmission)</td><td>Average (partial urban plans)</td><td>Limited (lack of documentation)</td><td>High (applied engineering)</td><td>Partial (few documented studies)</td><td>Complete (updated data)</td></tr><tr><th>Availability of energy data</th><td>Low (dependence on wood and straw)</td><td>Average (intermittent electricity)</td><td>Average (wood, biomass, low access to solar)</td><td>High (stable access to electricity, solar)</td><td>Very low (dependence on local resources)</td><td>Average (electricity and mixed energies)</td></tr></tbody></table>

This table highlights the major differences between traditional and modern habitats based on the criteria studied in these three Sahelian localities. Table 5 below presents

the thermal properties of the materials used in the habitats

<table><caption>**Table 5:** Comparison of the thermal properties of the materials used in traditional and modern habitats</caption><thead><tr><th>Material</th><th>Type of housing</th><th>Density (kg/m³)</th><th>Specific heat capacity (J/kg·K)</th><th>Thermal conductivity (W/m·K)</th></tr></thead><tbody><tr><td>Raw earth (adobe)</td><td>Traditional</td><td>1600</td><td>1000</td><td>0.85</td></tr><tr><td>Stone</td><td>Traditional</td><td>2500</td><td>800</td><td>2.5</td></tr><tr><td>Wood</td><td>Traditional</td><td>600</td><td>2300</td><td>0.12</td></tr><tr><td>Traditional Material Average</td><td></td><td>1566,67 ± 950,44</td><td>1366,67 ± 814,45</td><td>1,16 ± 1,22</td></tr><tr><td>Fired brick</td><td>Modern</td><td>1800</td><td>840</td><td>1.31</td></tr><tr><td>Concrete</td><td>Modern</td><td>2300</td><td>880</td><td>1.28</td></tr><tr><td>Cement block</td><td>Modern</td><td>2000</td><td>1000</td><td>1.75</td></tr><tr><td>Medium Modern Material</td><td></td><td>2033,33 ± 251,66</td><td>906,67 ± 83,27</td><td>1.45 ± 0.26</td></tr></tbody></table>
Ces données permettent de comparer les
performances thermiques des matériaux

traditionnels et modernes utilisés dans ces
régions sahéliennes.

<figure><img src="image_1.png" /><figcaption>Photo: Traditional dwellings a) in stone, b) in raw earth + stone and c) in raw earth</figcaption></figure>

Traditional materials, such as raw earth and stone, generally offer better natural thermal regulation, while modern materials often require additional insulation solutions to achieve equivalent thermal comfort (Zhixuan, et al., 2023; Bhartendu and Shailendra, 2024).

## 3.1. Scientific Analysis and Discussion of Thermal and Environmental Properties of Building Materials

### 3.1.1. Visualization of Curves

<figure><img src="image_2.png" /><figcaption>**Figure 1:** Visualization of thermal and environmental properties of materials</figcaption></figure>

Visualizing the thermal and environmental
properties of materials allows us to better
understand their impact on the thermal
comfort and sustainability of buildings. By
graphically representing thermal

conductivity, specific heat capacity,
embodied energy and CO₂ emissions, we
can compare traditional and modern
materials in terms of performance.
<figure><img src="image_3.png" /><figcaption>**Figure 2:** Comparison diagrams of different material properties</figcaption></figure>
Visualizing the different material properties as bar charts allowed to show a key parameter of each material in each graph.

### 3.1.2. Thermal Properties Analysis

#### 3.1.2.1. Density and Specific Heat Capacity

Specific heat capacity is an important indicator to assess the thermal inertia of a material. Wood, with a thermal capacity of 2,300 J/kg·K, has good heat retention, unlike stone (800 J/kg·K) or fired brick (840 J/kg·K). However, the higher density of materials such as concrete (2,300 kg/m³) can compensate for this thermal capacity by

increasing their overall thermal inertia (Zhao et al., 2019; Zhaoru et al., 2022).

#### 3.1.2.2. Thermal Conductivity

Materials with low thermal conductivity, such as wood (0.12 W/m·K), provide better thermal insulation, thus limiting heat loss. In contrast, stone (2.5 W/m·K) and cement block (1.75 W/m·K) have higher conductivities, making their use less efficient for thermal insulation, except in combination with additional insulation strategies (Dileep et al., 2020; Castro et al., 2025); Dzokom et al., 2024a,b).

<figure><img src="image_4.png" /><figcaption>**Figures 3:** Comparison of day/night variations of parameters (Temperature, Humidity, Heat Flow and Solar Irradiation) in modern and traditional habitats in the arid mountainous Sahelian zone of Cameroon over a period of 12 months.</figcaption></figure>

Each graph shows the evolution of the parameters with distinctions between day/night and traditional/modern habitats.

### 3.1.3. Analysis, Interpretation and Scientific Discussion

The comparative study of climatic parameters between modern and traditional habitats in the arid Sahelian mountainous areas of Cameroon offers essential perspectives on the thermal comfort and energy efficiency of these structures.
<figure><img src="image_5.png" /><figcaption>Photo: Modern housing a) in raw earth, b) in raw earth + cement and c) in cement, d) in stone + cement</figcaption></figure>

This analysis is based on data observed over a full year, highlighting the diurnal and nocturnal variations in temperature, relative humidity, heat flux and solar irradiation.

### 3.1.3.1. Temperature (°C)

For traditional housing, daytime temperatures range from 25.5°C in December to 31.5°C in May, with nighttime temperatures ranging from 22.0°C in December to 26.0°C in May. For modern housing, higher daytime temperatures reach 36.0°C in May, and nighttime temperatures peak at 32.0°C in May. Traditional housing, built from materials such as stone and clay, has a high thermal inertia, allowing it to absorb heat during the day and release it slowly at night. This property contributes to more moderate temperature variations between day and night. In contrast, modern concrete housing, with different thermal conductivity, shows more pronounced temperature fluctuations, suggesting a lower capacity to regulate daily thermal variations.

Materials used in traditional constructions seem to offer better natural thermal regulation, promoting increased comfort for occupants. This observation is consistent with the principles of bioclimatic architecture, which values the use of local materials to optimize indoor thermal comfort (Cognard, 2023; Dzokom et al., 2024a,b).

### 3.1.3.2. Relative Humidity (%RH)

For traditional housing, daytime relative humidity ranges from 25% in May to 37% in December, with nighttime values of 40% in May to 54% in December. For modern housing, the lower daytime relative humidity ranges from 18% in May to 27% in December, and nighttime values of 22% in May to 35% in December. Natural materials such as clay and stones used in traditional housing have the ability to absorb and release moisture, contributing to more stable hygrometric regulation. Modern housing, built with less permeable materials, shows lower relative humidity levels, which can lead to a feeling of dry air and discomfort for the occupants.

Too low relative humidity can cause discomfort such as dry skin and mucous membranes. Traditional housing appears to be better suited to maintain comfortable indoor humidity, reducing the need for artificial control systems (Fang et al., 2023).

### 3.1.3.3. Heat Flux (W/m²)

In traditional housing, daytime heat flux ranges from 12W/m² in December to 28W/m² in May, while nighttime heat flux varies from 5W/m² in December to 14W/m² in May. Heat flux measurements in modern housing reveal high daytime values with a maximum of 55W/m² recorded in May. Nighttime heat flux also shows an increase, reaching 32W/m² in May. Traditional housing shows more moderate heat fluxes, suggesting better thermal insulation and an
ability to limit heat gain and loss. Modern housing, with higher heat fluxes, may be more prone to thermal variations, potentially requiring active air conditioning to maintain comfort.

Efficient heat flow management is crucial for thermal comfort and energy efficiency. Traditional housing appears to offer advantages in terms of natural heat flow regulation, reducing reliance on artificial heating or cooling systems (Zigeng et al., 2023).

#### 3.1.3.4. Solar Irradiation (W/m²)

Outdoors, daytime solar irradiation reaches 720W/m² in May, with nighttime values close to zero throughout the year. Solar irradiation is a key factor influencing indoor temperatures in homes. The materials and design of homes determine how this energy is absorbed, stored, and released, thereby affecting the thermal comfort of occupants. The integration of passive design strategies, such as optimal building orientation, the use of materials with high thermal inertia, and the implementation of solar protection, can help manage the impact of solar irradiation on habitats, thereby improving comfort and energy efficiency (Wang & Guo, 2022).

This comparative analysis highlights the advantages of traditional habitats in terms of natural thermal and hygrometric regulation, attributable to the use of local

materials and construction techniques adapted to the Sahelian climate. Modern habitats, although meeting industrial standards, could benefit from the integration of bioclimatic design principles to improve occupant comfort and reduce energy consumption.

### 3.1.4. Environmental Analysis

#### 3.1.4.1. Embodied Energy and CO₂ Emissions

Embodied energy, which represents the energy consumed during the manufacturing and transportation of the material, is a crucial criterion for assessing the ecological impact. Raw earth (0.45 MJ/kg) is the most environmentally friendly material, followed by stone (0.95 MJ/kg). On the other hand, cement blocks (6.79 MJ/kg) and fired bricks (4.5 MJ/kg) have significantly higher values, which indicates a significant environmental impact (Reddy & Kumar, 2019; Reddy, 2009; Rakesh et al., 2023; Laura et al., 2021, Dzokom et al., 2024b). The graph below visualizes CO₂ emissions (expressed in kg CO₂e/m²) in traditional, hybrid and modern housing in the cities of Mokolo, Mora and Kaélé. The contribution of various emission sources can be observed, such as:

* Scope 1: Direct emissions from materials.

* Scope 2: Emissions from energy consumed for manufacturing.

* Scope 3: Emissions from transport, maintenance and end of life.

<figure><img src="image_6.png" /><figcaption>**Figure 4:** Comparison of CO₂ emissions (in kgCO₂e/m²) for traditional, hybrid and modern habitats in Mokolo, Mora and Kaélé.</figcaption></figure>
Similarly, CO₂ emissions follow a similar trend: raw earth (0.06 kg CO₂e/kg) generates very few emissions, while cement blocks (0.96 kg CO₂e/kg) are the most polluting. This justifies the growing interest in using bio-based and local materials to reduce the carbon footprint of construction (Dzokom et al., 2024a; Cabeza et al., 2020;

Boquera et al., 2021; Dzokom, 2024; Cabeza et al., 2021).

### 3.1.5. Carbon Footprint and Ecological Footprint

Below is the table summarizing the cumulative CO₂ emissions curve (expressed in kg CO₂/m²) for the entire life cycle.

<table><caption>Table 6: Summary of cumulative CO₂ emissions (expressed in kg CO₂/m²) for the entire life cycle.</caption><thead><tr><td>Phase</td><td>Traditional Habitats (kg CO₂/m²)</td><td>Modern Habitats (kg CO₂/m²)</td><td>Relative Increase</td></tr></thead><tbody><tr><td>Extraction</td><td>0</td><td>0</td><td>0%</td></tr><tr><td>Construction</td><td>25</td><td>34.5</td><td>38%</td></tr><tr><td>Exploitation</td><td>55</td><td>75.9</td><td>38%</td></tr><tr><td>End of life</td><td>80</td><td>110.4</td><td>38%</td></tr><tr><td>Total</td><td>110</td><td>151.8</td><td>38%</td></tr></tbody></table>

This table illustrates that, for each phase, the initial carbon footprint of modern housing (in cement concrete) is on average around 35 to 40% higher than that of traditional housing (in stone and clay). By applying a multiplier factor of 1.38 (an increase of 38%) to the basic values for traditional housing, we obtained those for modern housing.

Emissions related to the extraction of materials are here considered negligible (or zero) to simplify our calculations, so that the difference begins to appear from the construction phase. For traditional housing, the construction phase generates around 25 kg CO₂/m², while for modern housing, this figure reaches around 34.5 kg CO₂/m², an

increase of around 38%. This same increase factor (38%) is applied to the operating and end-of-life phases, leading to a total carbon footprint of 151.8 kg CO₂/m² for modern housing compared to 110 kg CO₂/m² for traditional housing. Overall, the cumulative carbon footprint over the life cycle of modern housing turns out to be approximately 38% higher than that of traditional housing. This table thus makes it possible to clearly visualize the carbon footprint gap between the two construction typologies and serves as a support for graphic analyses and scientific discussions on the environmental impact of each approach.

<figure><img src="image_7.png" /><figcaption>Figure 5: Curve of cumulative CO₂ emissions (kg/m²) over the complete life cycle for traditional (in blue) and modern (in red) housing.</figcaption></figure>
Figure 5 illustrates that cement concrete, with its high embodied energy, represents a critical part of the carbon footprint of modern buildings. In contrast, stone and clay, which are less processed, have a smaller footprint.

### 3.1.5.1. Production and Extraction

The data indicate that the production of cement concrete is responsible for much higher CO₂ emissions than stone and clay. Figure 1 shows the cumulative CO₂ emissions per m² curve, demonstrating that the initial carbon footprint of modern

housing is on average 35 to 40% higher than that of traditional housing.

The curve shows a rapid rise in emissions for concrete during the production phase, followed by a plateau during operation for traditional buildings, while modern buildings maintain a slightly upward curve due to constant energy requirements.

### 3.1.5.2. Operation and End of Life

Figure 6 below Visualization of average values for in situ measurements and simulations.

<figure><img src="image_8.png" /><figcaption>**Figure 6:** Comparison of values for in situ measurements and simulations</figcaption></figure>

Each criterion is represented with its error bars to illustrate the variability of the data.

The table below gives the detailed values of the in situ measurements and simulations:

<table><caption>**Table 7:** Detailed with average values of in situ measurements and simulations</caption><thead><tr><td>Criterion</td><td>In situ measurements</td><td>Simulations</td></tr></thead><tbody><tr><td>Reduction in heating consumption (%)</td><td>19.8 ± 2.1</td><td>20.3 ± 1.8</td></tr><tr><td>Indoor temperature (°C, without heating)</td><td>18.5 ± 1.2</td><td>18.7 ± 1.0</td></tr><tr><td>Relative humidity (%)</td><td>52.4 ± 3.5</td><td>51.8 ± 2.9</td></tr><tr><td>End-of-life carbon footprint (kg CO₂e/m²)</td><td>15.2 ± 3.1</td><td>14.8 ± 2.8</td></tr><tr><td>Material recyclability rate (%)</td><td>82.7 ± 5.4</td><td>85.3 ± 4.9</td></tr><tr><td>Estimated lifespan of buildings (years)</td><td>85 ± 10</td><td>90 ± 8</td></tr></tbody></table>

In situ measurements of heating consumption show an actual reduction of 19.8±2.1%, consistent with simulations (20.3±1.8%). The relatively low standard deviation indicates good stability of the results. Stone/clay buildings maintain a

stable indoor temperature, with little variation between in situ and simulation. Natural materials regulate relative humidity well, with a slight difference between measurements and simulations. Natural materials have a low end-of-life carbon
footprint (≈15 kg CO₂e/m²) with carbon impact. Natural materials have a recyclability rate of over 80%, promoting their reuse and limiting waste. The lifespan of buildings made of traditional materials

exceeds that of concrete buildings. These results lead to an overall reduction in the carbon footprint of 30 to 40% for traditional housing compared to concrete buildings.

## 3.2. Energy Consumption and Thermal Comfort

<figure><img src="image_9.png" /><figcaption>**Figure 7:** Indoor temperature of traditional homes varying by ±2°C compared to the outdoor temperature (±4°C) for concrete homes.</figcaption></figure>

Simulations and measurements revealed that the green curve illustrates a notable thermal stability, attenuating temperature peaks during the day and night, unlike the orange curve which presents more marked fluctuations.

Figure 7 highlights the ability of stone walls to stabilize the interior temperature. This thermal inertia is essential to reduce the need for heating in the cold season and air conditioning in the dry season. These findings corroborate the work of Martin et al. (2021) which highlights the thermal efficiency of traditional constructions.

### 3.2.1. Subjective Comfort and Acoustics

Surveys revealed that 75% of occupants of traditional housing say they are satisfied with their thermal comfort, compared to 60% for modern housing. Acoustic measurements indicate better sound insulation in stone buildings, due to the density and thickness of the walls.

### 3.2.2. Energy Costs

Figure 8 presents a comparative diagram of annual energy costs related to heating and cooling. Traditional homes show reduced costs of 15 to 25%, in correlation with their thermal inertia and their natural temperature regulation.
<figure><img src="image_10.png" /><figcaption>**Figure 8:** Comparison of annual energy costs (in FCFA/m²) for heating and air conditioning in the two types of housing.</figcaption></figure>

The green bar (traditional housing) is significantly lower than the red bar (modern housing), indicating better energy efficiency in operation.

The diagram in Figure 8 highlights that, in the long term, traditional housing allows for significant energy savings. Although the initial cost of renovation or maintenance may be higher, the savings made in operation largely offset these investments.

# 4. Discussion

## 4.1. Adaptability of Materials to Climates

In the Sahelian climate, thermal inertia is a decisive parameter. Heavy materials such as raw earth and stone allow for regulating day/night temperature differences by storing heat during the day and releasing it at night.

## 4.2. Towards Sustainable Construction

The results show that preserving the environment requires the use of materials with low embodied energy and low CO₂ emissions, such as raw earth and wood. The integration of hybrid solutions, combining modernity and tradition, could optimize thermal comfort while minimizing the environmental impact (Fang et al., 2022).

Comparative analysis of construction materials highlights the importance of choosing materials based on climate, thermal performance and ecological impact.

Raw earth and wood appear to be relevant solutions for sustainable construction due to

their low environmental impact and good insulating properties.

The results obtained confirm several hypotheses put forward in the literature. According to Dumont et al. (2019), the use of local materials and the mastery of artisanal processes contribute to reducing the carbon footprint from the production phase. Our data, in line with those of Dumont et al. (2019) and Martin et al. (2021), are part of this trend, showing a significant reduction in emissions for traditional housing.

## 4.3. Limitations and Prospects for Improvement

Despite their strengths, traditional constructions have some limitations:

* Adaptability to Modern Standards: The integration of smart management technologies (home automation, controlled mechanical ventilation systems) can be complex in old buildings.

* Maintenance and Renovation: Conservation and renovation techniques require specific expertise in order to preserve heritage while improving energy performance.

* Diversity of Climatic Contexts: This study, focused on arid mountainous areas of the Cameroonian Sahel, must be supplemented by research in other climatic contexts to generalize the conclusions.

## 4.4. Towards a Hybrid Approach

The data suggest that a hybrid approach, combining the advantages of the thermal
inertia of traditional materials and the efficiency of modern technologies, could represent a solution for the future.

For example, the addition of a controlled mechanical ventilation (CMV) system or integrated photovoltaic panels could further reduce energy consumption while maintaining optimal comfort.

**5. Conclusion**

The comparative study presented demonstrates that traditional stone and clay housing has significant environmental and energy advantages over modern cement concrete constructions. In particular:

* A reduced carbon footprint from the production phase and throughout the life cycle.

* A higher thermal inertia allowing better regulation of the interior temperature.

* Lower operating energy costs and increased occupant satisfaction in terms of thermal and acoustic comfort.

These findings pave the way for a gradual integration of traditional know-how into hybrid construction projects. These solutions could reconcile the requirements of sustainability, energy efficiency and comfort while enhancing the built heritage. Future work should deepen the economic analysis over the entire life cycle, extend the study to various climates and integrate technological innovations to optimize the performance of hybrid housing.

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