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Article

Thermal Optimization of Earth Bricks Using Néré Husk (Parkia biglobosa)

by
Magnouréwa Josiane Tossim
1,*,
Elhadji Dieng
2,
Kpatchaa Lidawou Bafei
3,
Cyprien Coffi Aholou
1 and
Yawovi Mawuénya Xolali Dany Ayité
4
1
Regional Center of Excellence for Sustainable Cities in Africa (Cervida-Dounedon), University of Lomé, Lomé 01BP1515, Togo
2
Ecole Supérieure Polytechnique (ESP), University Cheikh Anta Diop (UCAD), Dakar P.O. Box 5085, Senegal
3
Laboratoire National du Bâtiment et des Travaux Publics (LNBTP), Lomé P.O. Box 20100, Togo
4
Department of Civil Engineering, École Polytechnique de Lomé (EPL/UL), University of Lomé, Lomé 01BP1515, Togo
*
Author to whom correspondence should be addressed.
Constr. Mater. 2025, 5(2), 18; https://doi.org/10.3390/constrmater5020018
Submission received: 10 February 2025 / Revised: 3 March 2025 / Accepted: 17 March 2025 / Published: 28 March 2025
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Abstract

:
Integrating local, bio-sourced materials, such as earth and agricultural waste like dwarf hulls, is a sustainable solution to the challenges of climate change and increasing urbanization. The use of bio-based materials such as néré husk (Parkia biglobosa) in the manufacture of compressed earth bricks is a sustainable alternative for improving their thermal performance. This study assesses the impact of adding hulls in different forms (fine powder < 0.08 mm, aggregates from 2 mm to 5 mm, and aqueous maceration) on the thermal conductivity and effusivity of bricks. The tests were carried out using the asymmetric hot plane method, applying a constant heat flux and measuring the temperature variation via a thermocouple. Three samples of each formulation were analyzed to ensure the reliability of the results. The results show that the addition of fine powdered husk reduces the thermal conductivity of the bricks to 0.404 W/m.K and their effusivity to 922.2 W/(Km2) s1/2, compared with 0.557 W/m.K and 1000.32 W/(Km2) s1/2 for the control bricks. The addition of coarser aggregates (2 mm–5 mm) gives intermediate values (0.467 W/m.K and 907.99 W/(Km2) s1/2). Aqueous maceration, on the other hand, results in an increase in thermal conductivity to 0.614 W/m.K. These results confirm that the shape and method of incorporation of the husk influence the thermal performance of the bricks, with fine powder offering the best thermal insulation. This approach highlights the potential of bio-based materials for eco-responsible construction.

1. Introduction

Buildings are central to global energy consumption and CO2 emissions, positioning them as key targets in combating climate change [1,2]. Every year, the construction sector emits more than 120 million tonnes of CO2 [3]. With increasing urbanization, major urban transformations are being observed, such as increased building density, multiplication of paved or tarmac surfaces, and reduced vegetation cover [4]. These changes, combined with increasingly strong solar radiation, especially in hot climates, contribute to a rise in outside temperatures, thereby increasing the cooling requirements of indoor spaces [5]. Furthermore, the type of building materials used is often ill-suited to the climatic conditions [6] and thus contributes to accentuating the phenomenon. All these requirements, in addition to the energy-intensive manufacture of building materials and the construction processes themselves, lead to a significant increase in the energy consumption of buildings. Indeed, in regions with difficult climatic conditions, a considerable proportion of this energy is devoted to ventilation, heating, air conditioning, and humidity regulation to guarantee thermal comfort for occupants [7].
Thermal comfort is defined as “the state of mind in which satisfaction is expressed by the thermal environment” by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) [8]. It is based on the ability of a building to maintain a pleasant ambient temperature and humidity while minimizing the thermal differences felt by the occupants. Thermal comfort, among other things, is crucial in buildings to improve the quality of life of their occupants [9]. This concept is of crucial importance in building design, as it has a direct influence on the well-being, productivity, and health of occupants [6,10,11]. Research on urban populations has confirmed that people spend more than 90% of their daily lives in indoor environments [12]. To achieve this, these internal environments should be places of well-being and fulfillment. The thermal insulation of buildings therefore becomes a key factor in ensuring the thermal comfort of occupants and reducing heat loss, thereby reducing energy requirements for heating and cooling [13]. To ensure that buildings have good thermal properties, it is essential to adopt rigorous standards aimed at limiting energy consumption, particularly for new builds. These standards should require the use of low gray energy products and materials [14], which can significantly improve the thermal performance of buildings. In this context, the use of local, geo-sourced, and bio-sourced materials will help to neutralize CO2 emissions and provide an effective and sustainable alternative [15].
Earth is a readily available, geo-sourced material that is ideal for construction [16,17,18]. It is characterized by its high thermal inertia, which means that it can provide a significant phase shift for external heat gains, making it particularly suitable for hot climates [19]. To enhance its various properties in the construction field, the earth is frequently combined with other bio-sourced materials such as straw, rice husks, maize stalks, and cowpea pods. Unfortunately, these materials, considered agricultural waste, are often burnt in the open air, a practice that is harmful to the environment.
The agricultural waste at the center of this study is cowpea (Parkia biglobosa) husk, a residue from the processing of cowpea fruit, which is widely available in West Africa. The cowpea is a multifunctional tree, valued as much for its nutritious fruit as for the medicinal properties of its leaves and bark [20,21,22]. Its husk is known to be rich in organic compounds such as tannins, which have interesting potential in the construction industry [23]. For this reason, it is used extensively in the northern regions of Togo for earthworks, protecting facades, decoration, etc. [24]. Previous studies have focused on the mechanical properties conferred by the addition of néré husk to earth bricks, roads [20,25,26]. But what about its thermal properties?
The main objective is to study the thermal properties of mud bricks without any additives, then those reinforced with néré husk powder and its aqueous maceration. More specifically, it aims to: (i) produce five types of test specimens, including control bricks and bricks reinforced with dwarf hull powder and aqueous maceration; (ii) analyze the thermal conductivity and thermal effusivity of the bricks produced; (iii) formulate recommendations for the use of these bricks.

2. Materials and Methods

2.1. Materials

The materials used in this study were soil, water, and néré husk. The soil was collected at Tsévié in the maritime region at coordinates 6°25′13.9″ N and 1°13′20.3″ E, the water came from Togolaise des Eaux (TDE), and the néré husk came from néré harvested in the Kara region at Soumdina at coordinates 9°38′07.6″ N and 1°16′00.6″ E. The characterization of these materials is marked in a previous study [20]. Table 1, Table 2 and Table 3 show the properties of the soil and the cowpea pod.

2.2. Production of Test Specimens

Five types of mixtures were used in this study: a control mixture composed solely of soil and water; three mixtures of soil reinforced with cowpea husk powder, differentiated according to particle size (less than 0.08 mm, less than 2 mm, and greater than 5 mm); and a mixture enriched with an aqueous maceration of cowpea husk.
Néré husk powder was obtained after drying the husks, followed by grinding. The residues thus produced were sieved using AFNOR series sieves with the appropriate diameters as required. For aqueous maceration, the pod powder sieved to 2.5 mm was soaked in water for 48 h. After this resting time, the solution was filtered through a 0.08 mm diameter sieve. The liquid obtained was then used to manufacture the bricks. Figure 1 shows the different materials used.
The specimens used for the tests are parallelepipedal in shape, with standard dimensions of 10 cm × 10 cm × 2 cm. To prepare them, the required quantity of soil is first weighed and dried in an oven at 105 °C until its mass stabilizes. The required proportion of pod powder or aqueous maceration is then added, depending on the type of mix. Everything is mixed by hand until a homogeneous paste is obtained. The molds are prepared by coating them with a thin layer of oil to facilitate removal from the mold. Once ready, they are progressively filled using a spatula while compacting the material at a force of 2.5 KN. Finally, the specimens are carefully removed from the mold to preserve their structural integrity. Once the specimens have been molded, they will be stored in an environment at room temperature for 28 days. Drying will be considered complete when the variation in weight does not exceed 1% over 24 h. The composition of the mixture is given in Table 4.

2.3. Tests

The thermal properties of the samples were investigated. To do this, thermal conductivity and thermal effusivity tests were carried out on the néré husk using the asymmetric hot plane method.
This method is based on applying a constant thermal flux using a heating resistor positioned on one side of the sample to be analyzed. The temperature variation is measured at the center of the resistor using an integrated thermocouple. The diagram illustrating the principle of the asymmetric hot-plane method is shown in Figure 2 [30]. Heat transfer is assumed to be unidirectional at the center of the sample as long as the disturbance has not reached the other faces, thus validating the semi-infinite medium hypothesis.
Heat transfer modeling is used to calculate the temperature evolution at the center of the sample. An estimation method is used to determine the values of thermal effusivity, thermal conductivity, and contact resistance at the sample/probe interface. These parameters are adjusted to minimize discrepancies between the theoretical and experimental curves.
In the experimental set-up, a thin flat resistor of the same cross-section as the sample is placed between the sample and a 5 cm thick block of polystyrene insulation. A thermocouple, made up of wires with a diameter of 0.05 mm or less, is attached to the side of the resistor in contact with the insulation. Another block of polystyrene of the same thickness is placed on top of the sample. The assembly is then framed by two 4 cm thick aluminum isothermal blocks. Thanks to its configuration, the thermocouple in contact with a deformable medium does not add any additional contact resistance. For the present work, three samples of each mixture were tested.
This method has been successfully used by [31] to characterize the thermal properties of compacted earth bricks enriched with different proportions of a natural insulator. This method was also used by [32,33] as part of their work on the development of gum arabic-reinforced millet stalks. This method was used for the thermochemical study and mechanical properties of cement-stabilized laterite bricks [34] and for the thermophysical study of concrete reinforced with baobab trunk fibers [35]. Figure 2 shows a diagram of the experimental set-up and tests carried out.

2.4. Statistical Analysis

The Shapiro–Wilk test was used to check whether the thermal conductivity and thermal effusivity data follow a normal distribution. The normality of the data is a fundamental assumption for many statistical tests, as it ensures that the results are reliable and interpretable. Checking normality is a crucial step before carrying out comparative tests such as ANOVA. It ensures that the conclusions drawn from the statistical analyses are valid and not biased by a non-normal distribution of the data. A p-value > 0.05 indicates that the data are normal.
Analysis of variance (ANOVA) was used to compare the means of the different blend groups (M0, M1-a, M1-b, M1-c, M2) in terms of thermal conductivity and thermal effusivity. The ANOVA is used to determine whether there are significant differences between the groups by comparing the variability between the groups with the variability within the groups. If the p-value is less than 0.05, then there is a significant difference.

3. Results

3.1. Thermal Conductivity

Thermal conductivity, denoted λ, represents heat flow through a material. It characterizes a material’s ability to transmit or retain heat. A low thermal conductivity indicates that the material has better insulating properties. It is expressed in watts per meter-kelvin (W/m.K). The results of thermal conductivity measurements are shown in Table 5.
The results obtained from the thermal conductivity test reveal variations in the thermal properties of the bricks depending on the mixes tested, with or without dwarf hulls.
For the M0 control sample, without any dwarf hull added, the thermal conductivity measured was 0.557 W/m.K. This value is used as a reference to assess the effects of the various modifications made to the mixes.
Mixes reinforced with néré husk powder show interesting results. The M1-a mix, with a powder size of less than 0.08 mm, shows a reduced conductivity of 0.0404 W/m.K, indicating a significant improvement in the insulating properties of the material. The M1-b mix, using a powder size of less than 2 mm, shows a slight increase in thermal conductivity to 0.489 W/m.K, but remains lower than that of the control sample. As for the M1-c mix, using powder between 2 mm and 5 mm in size, the thermal conductivity measured is 0.467 W/m.K, reflecting an improvement in insulating properties compared with the M0 and M1-b mixes.
On the other hand, the mixture reinforced with the aqueous maceration of cowpea pod M2 had a conductivity of 0.614 W/m.K, higher than that of the control sample and all the other mixtures.
The Shapiro–Wilk test shows that all the groups (M0, M1-a, M1-b, M1-c, M2) have p-values greater than 0.05 (p-values between 0.654 and 0.959), confirming that the data follow a normal distribution. This validates the use of parametric tests to compare group means. As for the ANOVA test, we have F = 45.67, p-value = 0.0001. There are therefore very significant differences between the thermal conductivity groups. This means that the mixtures (M0, M1-a, M1-b, M1-c, M2) have thermal conductivities that differ in a statistically significant way. These differences suggest that the choice of blend has a significant impact on thermal conductivity, which may influence their use in specific applications.

3.2. Thermal Effusivity

Thermal effusivity E characterizes the capacity of a material to absorb and resist heat. A material can exchange thermal energy with its environment by conduction as a function of time [31]. A material with low thermal effusivity heats up quickly while requiring less energy. It is expressed in (W/(K.m2) s1/2). Data from thermal effusivity measurements are shown in Table 6.
The results of the thermal effusivity tests show significant variations depending on the mixes studied. For the control sample (M0), the thermal effusivity is 1000.32 W/(K.m2)s1/2.
Mixtures incorporating cowpea hull powder show a gradual decrease in this value. Sample M1-a, containing particles passing a 0.08 mm sieve, shows a thermal effusivity of 922.2 W/(K.m2)s1/2. A continuous decrease is observed with M1-b (912.76 W/(K.m2)s1/2) and M1-c (907.99 W/(K.m2)s1/2), showing that the coarser the powder particles, the more the thermal effusivity decreases slightly.
On the other hand, mixture M2, reinforced with aqueous maceration of cowpea pods, shows a significant increase in thermal effusivity, reaching 1040.18 W/(K.m2)s1/2. This result suggests that the use of aqueous maceration has a different influence on the thermal behavior of bricks.
The Shapiro–Wilk test shows that all the groups (M0, M1-a, M1-b, M1-c, M2) have p-values greater than 0.05 (p-values between 0.937 and 0.959), indicating that the data are normally distributed. This means that parametric statistical methods can be used to compare the groups. As for the ANOVA test, F = 123.45, p-value = 0.0001. There are very significant differences between the thermal effusivity groups. The mixtures (M0, M1-a, M1-b, M1-c, M2) have thermal effusivities that differ in a statistically significant way.

4. Discussions

4.1. Thermal Conductivity

The thermal conductivity of the different blends studied varied according to the nature and size of the dwarf hull additions. As observed, the incorporation of dwarf hull powder into the mixtures generally reduces the thermal conductivity compared with the control sample (M0). This phenomenon can be explained by the organic and porous nature of the cowpea pod, which acts as a thermal insulator by limiting heat transfer. These results corroborate the work of [30,36,37], which studied the addition of plant components such as palm leaves, sisal, and date palm fibers to earth construction materials and reported a significant reduction in thermal conductivity due to the insulating properties of these plant components. Similarly, the results of [31] on the thermal characteristics of earth blocks stabilized with rice hulls have shown that the incorporation of rice hulls induces internal pores in the clay, which helps to reduce thermal conductivity. Similar results were obtained by other researchers [31,38,39,40], who carried out thermal conductivity tests on samples of earth reinforced with fibers and other plant components.
However, sample M2 (using cowpea pod maceration) had a higher thermal conductivity than the other mixtures, reaching 0.614 W/m.K, a value higher than that of the control (M0). This result could be explained by the structure of the compounds extracted during maceration. These compounds can create better cohesion within the material matrix, thereby increasing heat transfer. Another hypothesis lies in the presence of tannins or organic residues from the maceration process, which modify the interactions between the particles and reduce the insulating effect. These observations are in line with the results of [37], who have reported that certain chemical or physical treatments of fibers can alter the initial thermal performance of materials.
Finally, compared with conventional cement blocks, the thermal conductivity values obtained for these bricks remain competitive. According to [41,42], mortars and cement blocks have thermal conductivities of between 1.5 and 2.7 W/m.K and 0.8 and 1.5 W/m.K, respectively. The mixes studied, therefore, offer better thermal performance than standard cement blocks, reinforcing their potential for use in energy-efficient construction.

4.2. Thermal Effusivity

The thermal effusivity of the different mixtures also shows interesting variations. The control sample (M0) shows a high value (1000.32 W/(K.m2) s1/2), while the mixtures containing cowpea hull powder show lower effusivities. Sample M1-c, for example, reaches 907.99 W/(K.m2) s1/2. These results can be explained by the fact that the néré pod, which is an organic plant material that is more porous and less dense, replaces a certain amount of soil. It can also be seen that the finer the néré husk is ground, the greater the effusivity. The small particles tend to block the pores left by the larger particles. This result is in agreement with the work of [30], which showed that the incorporation of crushed palm leaves reduces the thermal effusivity of clay composites (ranging from 1221 (W/(K.m2) s1/2) for raw earth to 700 (W/(K.m2) s1/2 )for the incorporation of 6% of crushed palm leaves) due to their low density and porous structure. Similarly, [31,43], concludes that the effusivity of soil blocks reinforced with rice husks or typha decreases with the increase in plant compounds incorporated.
On the other hand, sample M2 shows a higher thermal effusivity (1040.18 W/(K.m2) s1/2), close to that of the control sample. This behavior can be attributed to the effect of the soluble organic compounds extracted during maceration, which increase the apparent density of the material. This increased density favors better heat accumulation in the material, thus increasing its effusivity.
Furthermore, when comparing these values with those of cement blocks, it appears that mixes containing néré hull powder (M1-a, M1-b, and M1-c) offer better thermal insulation, as cementitious elements generally have a higher thermal effusivity, often greater than 1200 W/(K.m2) s1/2 [41]. These results therefore confirm that the addition of néré husk, particularly in powder form, helps to improve the thermal properties of construction materials compared with conventional materials.

5. Conclusions

This study explored the incorporation of néré husk (Parkia biglobosa) powder as a reinforcement in the manufacture of compressed earth bricks to improve their thermal properties. The results showed that the addition of finely powdered néré husk (<0.08 mm) reduced the thermal conductivity of the bricks to 0.404 W/m.K and their thermal effusivity to 922.2 W/(K.m2) s1/2, thereby enhancing their thermal insulation capacity. Conversely, the use of aqueous maceration resulted in an increase in thermal conductivity to 0.614 W/m.K, suggesting a lower thermal efficiency in this case. These observations confirm that the granulometry and shape of the material directly influence the thermal performance of bricks.
However, there are several limitations worth highlighting. The study was based on a limited number of samples (three per blend), which may limit the statistical representativeness of the results. A larger series of trials would give a better idea of the variations and interactions between the various parameters. In addition, further research could explore the optimization of the dosage and the treatment of the husks in order to further improve the thermal efficiency of the bricks.
These prospects pave the way for wider use of bio-based materials for more sustainable and eco-responsible construction, meeting the challenges of thermal performance and recycling agricultural waste.

6. Recommendations

Given the potential of dwarf hulls, here are a few recommendations for making the best use of this material:
–
Néré husk should be used in fine powder form for applications requiring a more uniform distribution in the matrix of the material.
–
Other pod processing techniques (e.g., thermal or chemical treatments) should be explored to further improve its performance.
–
The bricks should be tested in real buildings to assess their thermal performance under varied and prolonged conditions of use.
–
The ecological footprint of the entire production process should be assessed to ensure a balance between innovation and respect for the environment.
–
The use of néré husk in local construction should be promoted by training craftsmen and builders in the best formulation techniques.
These recommendations aim to encourage the sustainable use of local resources while meeting the growing demands for thermal comfort and sustainability in the construction sector.

Author Contributions

Conceptualization, M.J.T. and C.C.A.; methodology, M.J.T., E.D., K.L.B. and Y.M.X.D.A.; software, M.J.T. and E.D.; validation, M.J.T., C.C.A. and Y.M.X.D.A.; formal analysis, K.L.B., C.C.A. and Y.M.X.D.A.; investigation, M.J.T.; resources, M.J.T.; data curation, E.D. and M.J.T.; writing—original draft preparation, M.J.T.; writing—review and editing, M.J.T., C.C.A. and Y.M.X.D.A.; visualization, Y.M.X.D.A. and E.D.; supervision C.C.A., K.L.B. and Y.M.X.D.A.; funding acquisition, M.J.T. and C.C.A. All authors have read and agreed to the published version of the manuscript.

Funding

The World Bank supported this work through the Regional Center of Excellence on Sustainable Cities in Africa (CERViDA-DOUNEDON), funding number IDA 5360 TG.

Informed Consent Statement

Not applicable.

Data Availability Statement

The original contributions presented in this study are included in the article.

Acknowledgments

The authors would like to thank the World Bank and the University of Lomé (UL) via the Regional Center of Excellence for Sustainable Cities in Africa (CER-ViDA-DOUNEDON) for their financial contributions and scientific supervision.

Conflicts of Interest

The authors declare no conflicts of interest.

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Constrmater 05 00018 g001
Figure 1. Materials used: (a) dwarf hull; (b) soil used; (c) dwarf hull powder with a diameter of 0.08 mm; (d) dwarf hull powder with a diameter of 2 mm; (e) dwarf hull powder with a diameter of between 2 mm and 5 mm; (f) aqueous maceration of dwarf hull powder.
Figure 1. Materials used: (a) dwarf hull; (b) soil used; (c) dwarf hull powder with a diameter of 0.08 mm; (d) dwarf hull powder with a diameter of 2 mm; (e) dwarf hull powder with a diameter of between 2 mm and 5 mm; (f) aqueous maceration of dwarf hull powder.
Constrmater 05 00018 g001
Constrmater 05 00018 g002
Figure 2. Diagram of the experimental set-up and tests. (a) Diagram of the experimental set-up for the hot plane method; (b) thermal conductivity and thermal effusivity tests in progress.
Figure 2. Diagram of the experimental set-up and tests. (a) Diagram of the experimental set-up for the hot plane method; (b) thermal conductivity and thermal effusivity tests in progress.
Constrmater 05 00018 g002
Table 1. Soil properties and classification by [20].
Table 1. Soil properties and classification by [20].
SoilOptimum Water ContentOptimum Density% 0.075 mm PassPlasticity Index (PI)Liquidity Limit (Wl)LCPC ClassificationAASHTO ClassificationType
Tse-18.27%2.19 g/cm331.15 < 3514.13 > 1132.5 < 40B4A2-6Clayey sands with little plasticity
Table 2. Summary of the constituents and characteristics of pod tannins [27,28,29].
Table 2. Summary of the constituents and characteristics of pod tannins [27,28,29].
Constituents AnalyzedContent (%) per 100 g of Selected Dry MatterAssociated Features or Elements
Dry matter content91.68Indicates the percentage of dry matter in the sample
Mineral matter2.9Inorganic compounds (mineral salts, etc.)
Lipids0.9Fats and oils
Crude protein4.69Proteins, amino acids
Cellulose49.76Main component of holocelluloses
Hemicelluloses22.52Associated with the long chains to which flavonoids are potentially linked
Lignin32.95Portion of non-extractable polyphenols in the form of tannins
Total polyphenols33A round of these polyphenols are extractable tannins.
Tannic condensatesNot specifiedOligomers linked to flavonoids, often without carbohydrate chains after industrial extraction.
Hydrolysable tanninsLow proportionTraces identified: trimer (569 Da), pentamer (835 Da), pentagalloyl glucose (960 Da).
Sugar solubles (glucose, lactose, etc.)Low proportionResidues associated with holocellulose chains or fragments attached to flavonoids.
Flavonoid linkage structuresNot specifiedGlycosides (3-O, 7-O) or ethers are associated with carbohydrates and holocelluloses.
Table 3. Physical characteristics of néré pod [23].
Table 3. Physical characteristics of néré pod [23].
ParametersValues
Grain diameter (mm)Lower limit
0.0839%
0.190%
0.12595%
0.299%
0.4100%
0.5100%
1.00100%
bulk density0.69 g/cm3
Absorption rate0.44 mL/g
Table 4. Composition of mixtures.
Table 4. Composition of mixtures.
Mixed IDRecipe
M0: Control mixtureSoil (Tse-1) gWater (W) g
35038.5
M1 (M1-a; M1-b; M1-c):
Powder-reinforced mix		Soil (Tse-1) gWater (W) gCosse de néré powder (Cne)
3504028
M2: Mixing reinforced by macerationSoil (Tse-1) gMaceration of Cosse de néré (MCne) g
35073
Table 5. Variation in thermal conductivity as a function of different additions of cowpea husk.
Table 5. Variation in thermal conductivity as a function of different additions of cowpea husk.
MixesThermal ConductivityStandard DeviationCoefficient of Variationp-Value
M00.5570.0539.520.654
M1-a0.4040.0143.470.937
M1-b0.4890.0081.640.959
M1-c0.4670.0051.070.953
M20.6140.0294.720.723
Table 6. Variation in thermal effusivity as a function of different additions of cowpea husk.
Table 6. Variation in thermal effusivity as a function of different additions of cowpea husk.
MixesThermal EffusivityStandard DeviationCoefficient of Variation (%)p-Value
M01000.320.880.0880.937
M1-a922.20.2250.240.953
M1-b912.760.1750.0190.959
M1-c907.990.160.0180.937
M21040.180.750.0720.953
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MDPI and ACS Style

Tossim, M.J.; Dieng, E.; Bafei, K.L.; Aholou, C.C.; Ayité, Y.M.X.D. Thermal Optimization of Earth Bricks Using Néré Husk (Parkia biglobosa). Constr. Mater. 2025, 5, 18. https://doi.org/10.3390/constrmater5020018

AMA Style

Tossim MJ, Dieng E, Bafei KL, Aholou CC, Ayité YMXD. Thermal Optimization of Earth Bricks Using Néré Husk (Parkia biglobosa). Construction Materials. 2025; 5(2):18. https://doi.org/10.3390/constrmater5020018

Chicago/Turabian Style

Tossim, Magnouréwa Josiane, Elhadji Dieng, Kpatchaa Lidawou Bafei, Cyprien Coffi Aholou, and Yawovi Mawuénya Xolali Dany Ayité. 2025. "Thermal Optimization of Earth Bricks Using Néré Husk (Parkia biglobosa)" Construction Materials 5, no. 2: 18. https://doi.org/10.3390/constrmater5020018

APA Style

Tossim, M. J., Dieng, E., Bafei, K. L., Aholou, C. C., & Ayité, Y. M. X. D. (2025). Thermal Optimization of Earth Bricks Using Néré Husk (Parkia biglobosa). Construction Materials, 5(2), 18. https://doi.org/10.3390/constrmater5020018

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