Rammed earth walls in Mediterranean climate: material characterization and thermal behaviour

The conducted research examines the thermal behaviour of the rammed earth walls, which is the basic structural and fa?ade element of traditional Vojvodina house. The traditional rammed earth house represents an important part of the total building stock of Vojvodina. Earth is a locally available, cheap, natural, environmentally friendly building material and has been used extensively for traditional family houses in Vojvodina. It has ecological and ?green? characteristics, which can be assessed as very high quality, and they are of significant importance in the context of sustainable development and striving to reduce energy consumption today. The research examines thermal behaviour of rammed earth wall, including theoretical analysis of: the heat transfer coefficient, U, the thermal resistance, R, and thermal conductivity, ?. One of the basic elements of thermal behaviour, the thermal mass, has been analyzed both theoretically and by measuring in situ. The in situ measurements were conducted on the traditional house in Vojvodina by measuring inside and outside surface wall and air temperature in summer. Analyses of rammed earth wall thermal performances have shown that the wall has low thermal conductivity, high heat capacity and significant thermal mass effect which is the key element enabling thermal stability. The research indicates rather good thermal properties of the rammed earth walls. Potential of rammed earth wall in Vojvodina should be an issue of further analysis, although the possibility of improvement of existing facilities to meet current standards in terms of energy efficiency should be considered.

Download Full-text

Assessment of the Thermal Behaviour of Rammed Earth Walls in the Summer Period

Sustainability ◽

10.3390/su11071924 ◽

2019 ◽

Vol 11 (7) ◽

pp. 1924 ◽

Cited By ~ 2

Author(s):

Laura Balaguer ◽

Fernando Vegas López-Manzanares ◽

Camilla Mileto ◽

Lidia García-Soriano

Keyword(s):

Thermal Behaviour ◽

Climatic Factors ◽

Vernacular Architecture ◽

Thermal Inertia ◽

Rammed Earth ◽

Real Performance ◽

The Difference ◽

Earthen Architecture ◽

Earth Walls

The constructive solutions characteristic of vernacular architecture are the result of the convergence of geographical, cultural and climatic factors that bring about constructions characterised by adaptation to their surroundings. However, at present, Spanish regulations do not contemplate the properties of traditional materials, such as those found in earthen constructions, whose great thermal inertia is ignored despite their thermal gains and compensations. Given these limitations, the purpose of this study is to assess the thermal behaviour of traditional earthen architecture adjusting to its real performance and original surroundings. This work thus examines a methodology to assess the thermal behaviour of rammed earth walls based on on-site data specifically collected in the summer in a case study located in La Serranía, a region in the northwest of the province of Valencia (Spain). The results show the evolution of exterior and interior surface temperatures of the earthen wall, quantifying its variation frequency and thermal energy transmission. Based on these data, the thermal transmittance of the wall is calculated and compared to highlight the difference from the normalised value, showing that a review of the Spanish regulations applied to earthen architecture is needed.

Download Full-text

Design Optimisation Strategies for Solid Rammed Earth Walls in Mediterranean Climates

Energies ◽

10.3390/en14020325 ◽

2021 ◽

Vol 14 (2) ◽

pp. 325

Author(s):

Giada Giuffrida ◽

Maurizio Detommaso ◽

Francesco Nocera ◽

Rosa Caponetto

Keyword(s):

Energy Demand ◽

Construction Material ◽

Base Material ◽

Energy Performance ◽

Embodied Energy ◽

Rammed Earth ◽

Earth Construction ◽

Material Choice ◽

Earth Walls ◽

Raw Earth

The renewed attention paid to raw earth construction in recent decades is linked to its undoubted sustainability, cost-effectiveness, and low embodied energy. In Italy, the use of raw earth as a construction material is limited by the lack of a technical reference standard and is penalised by the current energy legislation for its massive behaviour. Research experiences, especially transoceanic, on highly performative contemporary buildings made with natural materials show that raw earth can be used, together with different types of reinforcements, to create safe, earthquake-resistant, and thermally efficient buildings. On the basis of experimental data of an innovative fibre-reinforced rammed earth material, energy analyses are developed on a rammed earth building designed for a Mediterranean climate. The paper focuses on the influences that different design solutions, inspired by traditional bioclimatic strategies, and various optimised wall constructions have in the improvement of the energy performance of the abovementioned building. These considerations are furthermore compared with different design criteria aiming at minimising embodied carbon in base material choice, costs, and discomfort hours. Results have shown the effectiveness of using the combination of massive rammed earth walls, night cross ventilation, and overhangs for the reduction of energy demand for space cooling and the improvement of wellbeing. Finally, the parametric analysis of thermal insulation has highlighted the economic, environmental, and thermophysical optimal solutions for the rammed earth envelope.

Download Full-text