Analysis of the Thermal Behavior of an Earthbag Building in Mediterranean Continental Climate: Monitoring and Simulation

Nearly 30% of humanity lives in earthen dwellings. Earthbag is a sustainable, cheap, feasible and comfortable option for emergency housing. A comparative monitoring-simulation analysis of the hygrothermal behavior of an Earthbag dwelling in Mediterranean continental climate, designed under bioclimatic criteria, is presented. The dome shape Earthbag dwelling has a net floor area of 7.07 m(2), a glass door facing south and two confronted windows in the east and west facades. A numerical model (EnergyPlus v8.8) was designed for comparison. Twenty-four hour cross ventilation, night cross ventilation, and no ventilation in free floating mode and a controlled indoor temperature were the tested scenarios. Comparisons between experimental data and simulation show a good match in temperature behavior for the scenarios studied. Reductions of 90% in summer and 88% in winter, in the interior thermal amplitude with respect to exterior temperatures are found. Position of the glazed openings was fundamental in the direct solar gains, contributing to the increase of temperature in 1.31 degrees C in winter and 1.37 degrees C in the equinox. Night ventilation in the summer period had a good performance as a passive system. Passive solar gains made a reduction of heating energy consumption of 2.3% in winter and 8.9% in equinox.