# Integrated Model for Eco-Renovation of Sustainable Housing: Between Local Innovation and Climate Resilience

Dsonwa Manfo, Giscard Desting Nimpa, Alexis Dzokom, Pettang Chrispin

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Dsonwa Manfo, Giscard Desting Nimpa, Alexis Dzokom, Pettang Chrispin. Integrated Model for Eco-Renovation of Sustainable Housing: Between Local Innovation and Climate Resilience. Sahel Nature Consulting Revue, In press, 08 (16), pp.1-17. [hal-05242669](https://hal.science/hal-05242669v1)

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# Integrated Model for Eco-Renovation of Sustainable Housing: Between Local Innovation and Climate Resilience

## Abstract

Scientific-Article Aout 2025, Volume 08, Issue 16

To address the growing climate challenges and energy insecurity in sub-Saharan Africa, Cameroon is exploring innovative approaches to adapt its housing stock. This article proposes an integrated model for eco-renovation of urban and peri-urban dwellings, combining local techniques, bio-based materials, and passive bioclimatic solutions. The study, conducted in Cameroonian cities across the Sudano-Sahelian zone, the Western Grassfields, and the Centre-South region, tested low-carbon devices such as stabilized compressed earth blocks (CEB), green roofs, natural ventilation, and reflective paints. Results show a significant improvement in thermal comfort (up to a 6°C reduction in indoor temperature) and an average 35% reduction in domestic energy costs. The participatory approach enhanced social acceptability and community ownership of the projects. This model, which aligns with strategies for improving existing buildings, supports climate resilience, sustainable urban adaptation, and the reduction of inequalities in access to healthy housing.

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# Integrated Model for Eco-Renovation of Sustainable Housing: Between Local Innovation and Climate Resilience

Dsonwa Manfo Ervé Destin¹², Nimpa Giscard Desting², Dzokom Alexis³, Pettang Chrispin²

1. Ministry of Housing and Urban Development-Cameroon / Department of Architecture and Housing Standards

2. Laboratoire de Civil Engineering et Mécanique, École Nationale Supérieure Polytechnique de Yaoundé, Université de Yaoundé I-Cameroun

3. Sahel Nature Consulting

Corresponding author: ervedestin@yahoo.fr

## Abstract

To address the growing climate challenges and energy insecurity in sub-Saharan Africa, Cameroon is exploring innovative approaches to adapt its housing stock. This article proposes an integrated model for eco-renovation of urban and peri-urban dwellings, combining local techniques, bio-based materials, and passive bioclimatic solutions. The study, conducted in Cameroonian cities across the Sudano-Sahelian zone, the Western Grassfields, and the Centre-South region, tested low-carbon devices such as stabilized compressed earth blocks (CEB), green roofs, natural ventilation, and reflective paints. Results show a significant improvement in thermal comfort (up to a 6°C reduction in indoor temperature) and an average 35% reduction in domestic energy costs. The participatory approach enhanced social acceptability and community ownership of the projects. This model, which aligns with strategies for improving existing buildings, supports climate resilience, sustainable urban adaptation, and the reduction of inequalities in access to healthy housing.

**Keywords:** Eco-renovation, thermal comfort, local materials, climate resilience, sustainable innovation, Cameroon

## Introduction

Climate change, with its cascade of extreme events such as droughts, floods, heatwaves, and strong winds, necessitates a fundamental rethinking of construction and spatial planning strategies, particularly in sub-Saharan countries, which face high environmental and socio-economic vulnerabilities. Cameroon, with its rich agro-ecological diversity, is no exception.

Its regions—specifically the Sudano-Sahelian zone, the Western Grassfields, and the Centre-South region—must address the combined effects of energy poverty, deforestation, scarcity of durable materials, and climatic hazards to achieve better housing quality, which is increasingly exposed to health and climate risks (Mbevo, 2019; Tchounga, 2020).
Integrated Model for Eco-Renovation of Sustainable Housing:
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In this context, there is a pressing need for
an integrated approach that links ecological
factors with building renovation. The
resulting model reconciles local innovation,
ecological sustainability, social inclusion,
and climate resilience by leveraging
indigenous knowledge, bio-based materials,
and construction practices adapted to each
ecological setting. According to Dsonwa et
al. (2021), Dsonwa et al. (2025) and
Dzokom (2025), climate adaptation
involves enhancing local resources and
vernacular knowledge, coupled with a
gradual modernization of construction
processes.

Research on integrated natural resource
management and community resilience in
Cameroon highlights the strategic role of
sustainable housing in reducing structural
and energy vulnerabilities. These studies
emphasize that “housing should not be
regarded solely as shelter, but as a lever for
adaptation and regeneration of local socio-
ecological systems” (Dsonwa et al., 2021, p.
43).

Several studies support this approach,
exploring sustainable urban planning
strategies in Africa by integrating low-
carbon local building dynamics (Dansou,
2022; Manet, 2015). Similarly, the
importance of participatory and
transdisciplinary approaches in eco-
renovation projects in Sahelian areas is
emphasized (Akplogan, 2024; Dzokom,
2025).

The approach proposed here structures a
model that modifies conventional
methods—often based on overconsumption
of resources, imported materials,
mimicking foreign practices, and high
carbon footprints—by introducing
alternatives such as locally available
materials with high thermal inertia (e.g.,
adobe, mud bricks, straw, millet stalks),

passive ventilation techniques, bioclimatic
housing layouts (Dsonwa et al., 2025, pp.
48–49), and community participation in the
design, implementation, and management
of these projects.

Thus, an integrated eco-renovation model
provides an opportunity to enhance the
resilience of housing to climate change
while promoting endogenous development
based on environmental justice, social
innovation, and energy efficiency in the
built environment. This model aligns with
the Sustainable Development Goals
(SDGs), particularly SDG 11 (sustainable
cities), SDG 13 (climate action), and SDG 7
(affordable and clean energy), contributing
to national strategies for resource efficiency
and adding value to the thematic codes for
building standards in Cameroon.

**Materials and Methods**

1. Geographical and Ecological Study
Framework

The study was conducted in three major
eco-climatic zones of Cameroon, selected
for their environmental, socio-cultural, and
architectural diversity:

<figure><img src="image_18.png" /><figcaption>Figure 1: Study Area</figcaption></figure>
Integrated Model for Eco-Renovation of Sustainable Housing:
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The Sudano-Sahelian zone covers the Extreme North region, including the Diamaré and Mayo-Kani departments. Its climate ranges from arid to semi-arid, with high solar exposure, limited woody resources, and annual rainfall below 700 mm (Mbevo, 2019).

The Grassfields zone covers the Western region, specifically the Menoua and Bamboutos departments, characterized by a sub-equatorial highland climate with moderate temperatures, rainfall exceeding 1500 mm, abundant availability of plant-based materials (such as bamboo, raphia, and Bambusa vulgaris), and clay-rich soils (Yengoh et al., 2010).

The Centre-South forested zone encompasses the Nyong-et-So'o, Mfoundi, and Lekié departments, with a predominantly humid equatorial climate, abundant woody resources, increasing population density, and precarious peri-urban housing conditions (Bissek, 1994).

## 2. Methodological Approach for Model Structuring

The study followed a multidisciplinary and cross-cutting approach, structuring the model across the following levels:

* **Level 1 – Documentary Analysis:** Systematic review of construction standards, indigenous practices, and ecological innovations in the sub-region.

* **Level 2 – Field Surveys:** Qualitative and quantitative surveys, including focus groups, semi-structured interviews, and participant observation conducted with artisans, household heads, local authorities, and NGOs (Akplogan, 2024).

* **Level 3 – Characterization of Local Materials:** Based on methods described by Dansou (2022), Manet (2015), and Toussakoe et al. (2021), including tests for thermal inertia, mechanical strength, hygroscopic capacity, and carbon footprint.

* **Level 5 – Bioclimatic Modeling and Thermal Simulations:** Performed using Ecotect and DesignBuilder software to evaluate the energy performance of renovated prototypes according to orientation, ventilation, and roof albedo (Kaboré, 2015).

* **Level 6 – Participatory Prototype Development:** Through community workshops and co-design sessions with local populations and technicians, integrating local knowledge and proposed eco-renovation solutions.

### 2.1. Adopted Analytical Model Structure

* **Step 1 – Definition of Overall Objectives:** Targeting a highly sustainable or bioclimatically efficient building.

* **Step 2 – Definition of General Durability Evaluation Parameters:** Selected and adapted to Cameroon's building sustainability challenges. Key parameters included materials and resources, energy, ecosystem impacts, quality of life, user comfort and health, local integration, economic viability, and population perception of adopted models.

* **Step 3 – Definition of Criteria:** Derived from specific thematic domains within each main parameter, relevant to construction in Cameroon (e.g., energy performance, applied standards, indoor temperatures, comfort rate,
Integrated Model for Eco-Renovation of Sustainable Housing:
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GHG emissions, local adaptation cost).

* **Step 4 – Performance Indicators:** Quantifiable metrics associated with each criterion.

* **Step 5 – Reference Thresholds:** Based on a comparative analysis of RT 2012 and RE 2020 tools, contextualized to various climatic zones in the country.

## 2.2. Definition of Building Sustainability Scores

Overall scores for bioclimatic efficiency (S) and durability were aggregated according to the criteria and key parameters, each normalized and weighted.

For bioclimatic efficiency (S):

$$S = w_1 \times E_T + w_2 \times C_T + w_3 \times V_N + w_4 \times P_S + w_5 \times I_T \quad (\text{Equation 1})$$

<table><thead><tr><td>Symbol</td><td>Criterion</td><td>Description</td><td>Weight (w<sub>i</sub>)</td><td>Rank</td></tr></thead><tbody><tr><td>E<sub>T</sub></td><td>Overall thermal efficiency</td><td>Average reduction of indoor temperature (°C)</td><td>0.3</td><td>1</td></tr><tr><td>C<sub>T</sub></td><td>Thermal comfort</td><td>% of time where indoor temperature is within comfort range</td><td>0.25</td><td>2</td></tr><tr><td>V<sub>N</sub></td><td>Natural ventilation (score/5)</td><td>Score calculated for natural ventilation</td><td>0.2</td><td>3</td></tr><tr><td>P<sub>S</sub></td><td>Solar protection (score/1)</td><td>Efficiency of shading devices (0-1)</td><td>0.15</td><td>4</td></tr><tr><td>I<sub>T</sub></td><td>Thermal inertia (normalized heat capacity)</td><td>Normalized heat capacity (0-1)</td><td>0.1</td><td>5</td></tr></tbody></table>

Local case studies (Garoua, Yaoundé, Dschang, Maroua, Bamenda) were selected for their ecological relevance, technological accessibility, and socio-cultural integration. Documentation included plans, photos, in-situ thermal surveys, and interviews with designers.

**For the Global Sustainability Index (GSI):** Indicators were aggregated to produce a composite GSI score, combining parameter scores through double summation based on the number of parameters and the mean of audited buildings. Durability was expressed on a Likert scale from 0 to 10: 0–3 for critical non-classified buildings, 4–6 for low sustainability, 6–8 for sustainable, and 8–10 for exemplary (highly sustainable).

## 2.3. Description of Tested Materials and Techniques

* **Sahelian Zone:** Compressed earth blocks (CEB), stabilized adobe walls with ash and cow dung, millet stalk roofs coated with clay-lime plaster.

* **Grassfields Zone:** Wattle and daub on bamboo or raphia frames, adobe blocks, double-pitched green roofs with maize stalks and palm leaves, cross ventilation.

* **Centre-South Zone:** Recovered wooden planks for partitions, stabilized raw earth bricks with latex or palm oil, aluminum sheet roofs insulated with kapok or plant fibers.
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**2.4. Building Evaluation Indicators**

Three categories of indicators were used:

* **Technical and Thermal Indicators:** Average indoor temperature, day/night temperature variation, relative humidity, air tightness, thermal inertia.

* **Socio-economic Indicators:** Production cost per unit, estimated lifespan, material availability, social acceptability, user appropriation rate (Dzokom et al., 2025).

* **Environmental Indicators:** Carbon footprint of materials (kg CO₂/m²), recyclability potential, landscape integration, dependency on fossil resources (Dansou, 2022; Manet, 2015).

Data were analyzed using SPSS for surveys and Pleiades, Equer, EnergyPlus, and Meteonorm for simulations and 3D visualization of prototypes.

**Results and Discussion**

**1. Technical and Thermal Results**

<table><caption>Table 1: Technical and Thermal Performance Results by Climatic Zone</caption><thead><tr><td>Measured Parameters</td><td>Sudano- Sahelian Zone</td><td>Grassfields Zone (West)</td><td>Centre-South Forest Zone</td></tr></thead><tbody><tr><td>Average indoor temperature (°C)</td><td>28.7 ± 1.5</td><td>24.2 ± 1.1</td><td>26.5 ± 1.3</td></tr><tr><td>Average outdoor temperature (°C)</td><td>37.5 ± 2.4</td><td>28.8 ± 2.0</td><td>31.6 ± 2.1</td></tr><tr><td>Indoor-outdoor temperature difference (ΔT, °C)</td><td>-8.8 ± 0.9</td><td>-4.6 ± 0.6</td><td>-5.1 ± 0.7</td></tr><tr><td>Indoor relative humidity (%)</td><td>44.2 ± 5.1</td><td>58.6 ± 4.9</td><td>62.1 ± 5.3</td></tr><tr><td>Wall thermal resistance (R, m²·K/W)</td><td>1.85 ± 0.12</td><td>1.62 ± 0.10</td><td>1.74 ± 0.11</td></tr><tr><td>Natural ventilation rate (vol/h)</td><td>5.3 ± 1.0</td><td>4.1 ± 0.8</td><td>3.7 ± 0.7</td></tr><tr><td>Estimated energy consumption (kWh/month/household)</td><td>32.4 ± 4.6</td><td>28.7 ± 3.9</td><td>30.1 ± 4.2</td></tr></tbody></table>

* **Centre-South Forest Zone:** Construction prototypes incorporating raw earth stabilized with palm oil or natural latex

Thermal performance tests on the renovated prototypes demonstrated a significant improvement in indoor thermal comfort compared to conventional buildings across the three study zones:

* **Sudano-Sahelian Zone:** Houses built with stabilized compressed earth blocks (CEB) combined with millet-stalk roofs coated with clay exhibited an indoor temperature reduction of 4–6°C compared to traditional cement-sheet houses (Toussakoe et al., 2021). The thermal transmittance (U-value) decreased from 2.5 W/m²·K (conventional housing) to 0.95 W/m²·K (eco-renovated housing).

* **Western Grassfields:** The use of wattle-and-daub on bamboo frames, combined with green roofs and bioclimatic orientation, provided stable daytime thermal conditions (+/- 2°C) and improved regulation of relative humidity (55–65%), in line with WHO recommendations (Dansou, 2022; Manet, 2015).

demonstrated good thermal inertia, reducing day/night temperature fluctuations from 8°C to 3°C. These houses also showed improved
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acoustic stability and greater
resistance to ambient humidity
(Bissek, 1994).

These results corroborate Kaboré (2015), who highlighted that building orientation, roof color, and natural high-mass materials are effective strategies to mitigate climatic effects in the built environment.

<figure><img src="image_19.png" /></figure>

(ΔT highest observed in the Sudano-Sahelian zone: significant thermal gain due to the eco-renovation model).

<caption>**Graph 1: Indoor vs Outdoor Temperature by Zone**</caption>

The results demonstrate that the integrated eco-renovation model significantly improves indoor thermal comfort across all studied climatic zones. In the Sudano-Sahelian zone, where outdoor temperatures reach up to 40 °C, an indoor-outdoor temperature reduction of more than 8 °C was observed, achieved through passive techniques such as:

* The use of locally available materials with high thermal inertia (e.g., wattle-and-daub, stabilized earth),

* Enhanced insulation of roofs and walls using local plant fibers (e.g., *Eichhornia crassipes*, rice straw),

* Cross-ventilation strategies (e.g., oriented openings, ventilated screens).

According to Holmer (1996), a temperature reduction exceeding 5 °C in arid zones using bioclimatic construction techniques significantly improves occupant productivity while reducing the risk of indoor thermal stress.

<figure><img src="image_20.png" /><figcaption>**Photo 1: Front Facade of Modern Unrenovated Buildings**</figcaption></figure>
# Integrated Model for Eco-Renovation of Sustainable Housing:
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* Sahelian Zone: (a) Mokolo and (d) Garoua

* Grassfields Zone: (b) Bafoussam and (f) Foumbot

* Centre-South Zone: (e) Yaoundé and (c) Kribi

In the **Grassfields Zone**, which is cooler and more humid, the adjusted eco-renovation model optimized nighttime thermal losses, improving hygrothermal comfort. Materials such as woven bamboo and compressed earth bricks proved effective in maintaining stable indoor temperatures.

In the **Centre-South Zone**, with a more equatorial climate, moderate performance was observed with a good balance between indoor temperature and relative humidity. Roof greening and natural ventilation helped stabilize indoor microclimates.

In summary:

* The $\Delta T$ (indoor-outdoor temperature difference) was highest in the Sudano-Sahelian zone,

demonstrating the high insulating efficiency of local materials and adapted architectural forms.

* **Wall thermal resistance (R)**, generally above 1.6 m²·K/W, meets bioclimatic building standards for hot-dry climates (ISO 13790).

* **The reduction in monthly energy consumption** (up to 30–35%) indicates minimal or no need for air conditioning, aligning with Givoni (1994) on passive system performance in tropical environments.

## 2. Socio-Economic Results

The cost-benefit analysis of materials and techniques revealed that eco-renovated houses are **20–40% less expensive** than conventional block houses with imported metal roofs, particularly during the construction phase. For instance, in the Sahelian zone, the average cost of an eco-renovated unit is estimated at **350,000–480,000 FCFA**, compared to **600,000–900,000 FCFA** for a conventional industrial-material house (Akplogan, 2024).

<table><caption>Table 2: Socio-Economic Results of the Eco-Renovation Model</caption><thead><tr><td>Socio-Economic Indicators</td><td>Sudano-Sahelian Zone</td><td>Grassfields Zone (West)</td><td>Centre-South Zone</td></tr></thead><tbody><tr><td>Average renovation cost per dwelling (FCFA)</td><td>185,000 ± 15,200</td><td>230,000 ± 18,400</td><td>210,000 ± 17,100</td></tr><tr><td>Local employment rate generated (%)</td><td>67.4 ± 5.8</td><td>58.6 ± 6.2</td><td>60.9 ± 5.5</td></tr><tr><td>Use of local materials (%)</td><td>84.3 ± 4.5</td><td>77.1 ± 6.0</td><td>80.5 ± 5.2</td></tr><tr><td>Reduction in monthly energy expenses (%)</td><td>42.5 ± 6.1</td><td>35.2 ± 5.9</td><td>38.7 ± 5.3</td></tr><tr><td>Community acceptability of the model (%)</td><td>79.8 ± 7.4</td><td>72.4 ± 8.1</td><td>75.1 ± 6.9</td></tr><tr><td>Net daily productivity gain for households (%)</td><td>14.7 ± 2.4</td><td>11.3 ± 2.0</td><td>12.8 ± 1.9</td></tr><tr><td>Average payback period (months)</td><td>11.4 ± 1.6</td><td>13.7 ± 1.8</td><td>12.6 ± 1.7</td></tr></tbody></table>
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Additionally, mobilizing **local resources** (e.g., earth, bamboo, fibers, organic and agricultural residues) and **artisan labor** created **15-25 % additional employment** in target communities. This process

strengthened traditional skills, particularly in the Dschang area (West), where artisans improved ancestral techniques under the guidance of project engineers (Yengoh et al., 2010).

<figure><img src="image_21.png" /><figcaption>Graph 2: Comparison of Three Key Indicators by Zone</figcaption></figure>

**1. Cost and Return on Investment**

Lowest renovation costs were observed in the **Sudano-Sahelian Zone** (185,000 FCFA ± 15,200), thanks to abundant inexpensive local materials (e.g., wattle-and-daub, dry stones, straw, local timber). The **fast payback period** (11.4 months ± 1.6) is associated with high energy savings (up to 42.5 %), consistent with Enshen (2005) on passive construction in Sub-Saharan Africa.

**2. Job Creation and Local Economic Dynamism**

The model stimulated **local employment**, especially in the Sahelian zone (67.4% ± 5.8), mobilizing artisans, carpenters, and masons. This aligns with Barrière & Barrière (1997), highlighting the multiplier effect of endogenous eco-innovations on rural economies.

**3. Use of Local Materials**

High local material use (>80% on average) reduces the carbon footprint of the construction process while revitalizing vernacular knowledge (e.g., stabilized earth, green roofs), as recommended by Doat et al. (2014) and Givoni (1994).

**4. Improvement in Quality of Life**

Community acceptability (>75%) indicates strong adoption, driven by economic benefits (lower bills), thermal comfort, and cultural/esthetic considerations. **Daily productivity gains** (up to 14.7%) are linked to improved indoor comfort, reducing heat-related fatigue, in agreement with Holmer (1996) on human performance in buildings.

**3. Environmental Results**
Integrated Model for Eco-Renovation of Sustainable Housing:
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The **carbon footprint** of local materials used in the eco-renovation models ranged from 0.12 to 0.25 kg CO₂-eq/m², compared to 1.2–2.4 kg CO₂-eq/m² for industrial materials (e.g., cement blocks, corrugated

metal sheets, industrial paints), confirming the findings of Dansou (2022), Manet (2015), Dzokom et al. (2025), and Mbevo (2019) on the environmental burden of the construction sector in Cameroon.

<table><caption>Table 3: Environmental Results of the Integrated Eco-Renovation Model</caption><thead><tr><th>Environmental Indicators</th><th>Sudano-Sahelian Zone</th><th>Grassfields Zone (West)</th><th>Centre-South Zone</th></tr></thead><tbody><tr><td>Reduction of CO₂ emissions (kg/dwelling/year)</td><td>238 ± 21</td><td>192 ± 18</td><td>210 ± 19</td></tr><tr><td>Reduction of construction waste (%)</td><td>72.5 ± 5.3</td><td>65.2 ± 6.0</td><td>68.4 ± 5.7</td></tr><tr><td>Material recycling rate (%)</td><td>64.8 ± 6.2</td><td>59.1 ± 5.8</td><td>61.7 ± 6.0</td></tr><tr><td>Reduction of water footprint (%)</td><td>18.3 ± 2.6</td><td>15.1 ± 2.3</td><td>16.4 ± 2.5</td></tr><tr><td>Increase in vegetation cover (%)</td><td>12.6 ± 2.2</td><td>9.7 ± 1.9</td><td>11.3 ± 2.1</td></tr><tr><td>Integration of eco-systemic techniques (%)</td><td>82.1 ± 5.5</td><td>74.8 ± 5.2</td><td>78.5 ± 5.6</td></tr></tbody></table>

In all three zones, **eco-renovation** reduced dependency on imported materials (up to 60%), promoted circular economy practices (reuse of stalks, ash, animal dung, plant residues), and valorized agricultural organic waste as insulation or stabilization material.

## 1. Reduction of CO₂ Emissions

The integrated eco-renovation model significantly reduces CO₂ emissions, reaching **238 kg/dwelling/year** in the Sahelian zone due to:

* Substitution of industrial materials with **bio-based materials** (earth, straw, local fibers),

* Reduction of mechanical and thermal energy use during and after renovation.

According to Nègre (2006), each ton of cement saved avoids 900–1000 kg of CO₂. By replacing cement with wattle-and-daub or compressed earth bricks (CEB), the reductions become substantial.

## 2. Waste Reduction and Recycling

Construction waste reduction reached **72.5 %** in the Sahelian zone through:

* Reuse of locally sourced materials (stones, bricks, wood),

* Modular and demountable techniques (light partitions, recyclable green roofs).

These approaches align with González & Navarro (2006), who advocate "zero waste" as a key sustainability indicator in eco-construction.
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<figure><img src="image_22.png" /></figure>

Visualization: The model performs best environmentally in the Sahelian zone.

Axes:

* Avoided CO₂ emissions

* Material recycling

* Construction waste

* Water footprint

* Vegetation cover

* Eco-systemic integration

**Graph 3: Visualization of environmentally performances (by % or kg depending on indicator)**

**3. Reduction of Water Footprint**

The integration of **green roofs**, **rainwater harvesting systems**, and **low-gray-water materials** reduced the water footprint by up to 18%, particularly in the Sahelian zone. This aligns with Hoekstra & Chapagain (2007) on building water footprints.

**4. Effects on Biodiversity and Vegetation**

Revegetation of surroundings (windbreak hedges, green roofs) increased vegetation cover by 9–13% depending on the zone. In the Sahelian zone, local species such as *Azadirachta indica* and *Pennisetum sp.* were used for soil stabilization and microclimate creation.

According to **UN-Habitat (2021)**, these interventions enhance urban and rural **ecosystemic resilience** in climate-vulnerable areas.

**5. Eco-Systemic Integration Rate**

This indicator measures the use of practices such as:

* Dry toilets

* Composting

* Green roofs

* Greywater reuse

* Bio-based insulation

High integration rates (>80% in the Sahelian zone) demonstrate a **circular and**
Integrated Model for Eco-Renovation of Sustainable Housing:
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regenerative approach, consistent with
principles of circular bioclimatic
architecture (Rode et al., 2019).

that are territorially grounded, culturally
accepted, and ecologically viable.”

4. Social Acceptability and Perceived
Resilience

More than **78 % of households** surveyed across the three zones reported high satisfaction with the tested construction prototypes, highlighting the following benefits:

* Reduction of energy expenses (less need for air conditioning or fans),

* Decrease in heat- or humidity-related illnesses (malaria, heatstroke, respiratory disorders),

* Sense of pride and ownership of modernized local techniques.

These findings align with Dzokom et al. (2025), who state that: "Climate resilience in local contexts is not decreed; it is built through popular appropriation of solutions

The diversity of ecological contexts studied also helped identify **key success factors** for an integrated eco-renovation model, including co-construction of projects with communities, valorization of local knowledge, adaptation of materials to regional climatic constraints, and technical/financial support for initiative leaders.

1. High Social Acceptability in the Sahelian Zone

Household satisfaction rates (82.6 %) and perceived improvement in thermal comfort (88.4 %) were highest in the **Sudano-Sahelian zone**, demonstrating strong alignment between the model and the extreme climatic needs of built environments. Users reported improved **day- and nighttime comfort**, enhanced ventilation, and reduced health risks associated with heat.

<table><caption>Table 4: Social Acceptability and Perceived Resilience of the Eco-Renovation Model</caption><thead><tr><td>Measured Indicators</td><td>Sudano- Sahelian Zone</td><td>Grassfields Zone (West)</td><td>Centre-South Zone</td></tr></thead><tbody><tr><td>Household satisfaction rate (%)</td><td>82.6 ± 6.1</td><td>76.3 ± 5.7</td><td>78.1 ± 5.9</td></tr><tr><td>Perceived improvement of thermal comfort (%)</td><td>88.4 ± 5.8</td><td>79.1 ± 6.0</td><td>81.7 ± 5.6</td></tr><tr><td>Community engagement in the project (%)</td><td>74.2 ± 6.4</td><td>69.8 ± 5.9</td><td>72.5 ± 6.0</td></tr><tr><td>Integration of local knowledge into renovations (%)</td><td>86.7 ± 5.5</td><td>79.2 ± 6.3</td><td>82.4 ± 5.4</td></tr><tr><td>Perceived resilience to climatic hazards (%)</td><td>81.9 ± 5.3</td><td>73.5 ± 5.7</td><td>76.8 ± 5.1</td></tr><tr><td>Intention to replicate/disseminate the model (%)</td><td>64.3 ± 7.0</td><td>58.9 ± 6.5</td><td>62.1 ± 6.6</td></tr></tbody></table>

These results corroborate Holmer (1996), who emphasized the direct impact of temperature on perceived comfort and productivity in hot regions.

2. The Key Role of Local Knowledge in Construction Practices

The integration of **traditional knowledge** (86.7 % in the North) strengthened community ownership of the project by combining ancestral techniques (e.g., Nubian vaults, banco walls) with climate-adaptive innovations. This approach aligns with Barrière & Barrière (1997) regarding
# Integrated Model for Eco-Renovation of Sustainable Housing:
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the socio-cultural legitimacy of eco-
construction projects.

<figure><img src="image_23.png" /></figure>

Axes:

* Household satisfaction

* Perceived thermal comfort

* Community engagement

* Integrated local knowledge

* Perceived resilience

* Intention to replicate

## Graph 4: Visualization of Key Role of Local Knowledge in Construction Practices
(scoring in %)

### 3. Perceived Resilience and Climate

Households perceive their renovated homes
as **more resilient to heatwaves, heavy rainfall, and strong winds**, due to:

* Improved natural insulation,

* Strengthened and ventilated roofs,

* Use of locally sourced thermoregulating materials.

Perceived resilience reached **81.9 % in the North**, compared with **73.5 % in the West**, illustrating the positive impact of eco-renovation on residents' confidence in the face of climate change (IPCC, 2022).

### 4. Intention to Disseminate

The **community intention to replicate the model** (62–64 %) is moderately high, constrained mainly by:

* Limited initial financial resources,

* Insufficient institutional awareness,

* Difficult access to certain materials (e.g., bamboo, compressed earth bricks – BTC).

Nevertheless, the approach is considered **transferable and adaptable** to other villages, neighborhoods, and urban centers according to the surveyed populations.

## Conclusion and Recommendations

### Conclusion

The comparative analysis conducted across the three major ecological zones of Cameroon demonstrates the **relevance and feasibility** of an integrated eco-renovation model for housing, based on the synergy between local innovation, ecological sustainability, and climate adaptation. The results indicate that **bio-based materials** (such as raw earth, plant fibers, millet stalks, bamboo, animal dung, and plant ash)
Integrated Model for Eco-Renovation of Sustainable Housing:
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© Aoùt 2025, Volume 08, Issue 16 | https://sites.google.com/view/sahel-nature-consulting/accueil

combined with **enhanced vernacular construction techniques** (e.g., wattle and daub, stabilized BTC, green roofs, passive ventilation) lead to significant improvements in **thermal and environmental performance** of dwellings.

In all three targeted zones – Sahelian, Grassfields, and forested regions – the tested construction prototypes helped:

* Reduce extreme indoor temperatures,

* Lower the carbon footprint of materials,

* Decrease construction costs, and

* Strengthen the integration of local knowledge within modern resilience strategies.

Thus, the eco-renovation model emerges as a **strategic lever** for climate resilience, reduced energy vulnerability, and enhanced social equity in access to healthy and sustainable housing.

Consistent with Dsonwa et al. (2021), this model emphasizes that **integration of community knowledge, valorization of local resources, and active participation of populations at all project stages** are essential conditions to ensure the sustainable embedding of ecological innovations in the housing sector.

## Recommendations

### 1. For Public Decision-Makers:

* Integrate eco-renovation models into national housing, spatial planning, and climate resilience policies, including the **National Adaptation Plan (NAP)** and the **National Development Strategy 2030 (NDS30)**.

* Subsidize ecological local materials (e.g., stabilized earth, plant fibers, bamboo) and create **tax incentives** for artisans or developers incorporating eco-construction in their projects.

* Support **standardization and certification** of alternative materials (BTC, adobe, improved wattle and daub) to promote their recognition in national building codes.

### 2. For Local Authorities and Municipalities:

* Promote **community pilot projects** in rural and urban areas, demonstrating the benefits of integrated eco-renovation.

* Organize **training workshops** for local artisans and technicians on the use of natural materials and bioclimatic principles.

* Integrate eco-renovation approaches into **participatory urban planning and local development programs**.

### 3. For Researchers and Academic Institutions:

* Conduct in-depth research on the **thermal and mechanical performance of local materials** under different climatic contexts.

* Evaluate the **long-term social, health, and economic impacts** of eco-renovated housing, aligned with the **Sustainable Development Goals (SDGs 7, 11, 13)**.

* Develop **simplified educational models** for the dissemination of sustainable architecture principles in schools and training centers.

### 4. For Communities and NGOs:
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* Encourage **co-production of housing**, involving beneficiary families in design and construction phases.

* Strengthen **circular economy dynamics**, particularly through the valorization of agricultural residues and organic waste as construction resources.

* Mobilize **cultural, ritual, and aesthetic knowledge** associated with traditional housing to enhance the social acceptability of innovations.

Ultimately, the integrated eco-renovation model represents a **strategic pathway** for improving the quality of life of Cameroonian populations while addressing global imperatives of ecological transition, climate adaptation, and territorial cohesion. It is not only a technical innovation but also a **societal commitment** toward more sustainable, equitable, and resilient housing.

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