Despite the far distance between Portugal and Egypt, it was possible to find points of similarity on the influence of Roman and Arab cultures, and on solar passive and construction techniques used in vernacular architecture. Earthen construction techniques are one of these examples, being used in both countries for thousands of years. Through an explanatory qualitative and quantitative analysis, this paper presents an overview of the effects of climate-responsive strategies on thermal performance and indoor comfort of earthen architecture from Northern Egypt and Southern Portugal. To understand the effectiveness of these strategies, measurements of hygrothermal parameters and surveys on occupants’ thermal sensation were conducted in two case studies. From the results, it has been found that the case studies have shown a good thermal performance only by passive means and that the occupants expressed as being comfortable. Thus, vernacular passive strategies still can contribute to achieve indoor comfort conditions and reduce the dependency on mechanical systems.