This study addresses passive adaptation strategies to reduce the effects of global warming on housing, focusing on low-income houses, for which passive adaptation strategies should be prioritized, aiming for environmental sustainability. The passive strategy chosen is thermal mass for cooling, through the adoption of earth-sheltered walls in contact with the ground. Thus, the goal of this study is to evaluate the thermal load and thermal impact of implementing a thermal mass strategy for cooling, using bermed earth-sheltered walls in bedrooms, for a building located in a tropical climate region. For that, a base scenario (1961–1990) is considered alongside two future scenarios: 2020 (2011 to 2040) and 2050 (2041 to 2070), both considering the effects of climate change, according to the Fourth Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC). The methodologies adopted are (i) the computational simulation of the annual thermal load demand and (ii) the quantification of the Cooling Degrees-Hours (CDH) with the subsequent comparative analysis. The results show that in both the 2020 and 2050 scenarios there will be an increase in the thermal loads for cooling and the CDH, regardless of using a bermed earth-sheltered wall. Nonetheless, it is shown that this passive strategy works as a global warming adaptation measure, promoting building sustainability in tropical climate regions.