Assessing vulnerability at the household level to urban heat is one of the important processes toward understanding the current challenges on heat-related health issues, limitations in local level disaster response, and potential future risk of the community, especially in informal settlements. This can guide the development of local level urban heat risk reduction plans and integrate in current policies and strategies regarding housing, climate and disaster risk. People in informal settlements are involved in the vital role of the country’s economy and social cohesiveness. By measuring the vulnerability, the local level can be prepared with proper planning based on the method proposed in this paper. In addition, the influencing factors that inhibit resilience of urban poor communities are highlighted here. The methodological tool presented here can serve as a foundation for the establishment of an urban heat effect assessment plan and housing policy, thereby building disaster resilience of informal settlements. The results of the household-level vulnerability survey indicate that the study region has a low level of vulnerability to urban heat, with a score of 0.2 out of 1. With a coping capacity of 0.8, the community had a high level of coping capacity when a heatwave occurs. In comparison, the level of exposure was 0.52 and the level of sensitivity was 0.32. However, the community is confronted with difficulties with substandard living conditions, including insufficient ventilation, limited cooling systems, and inhabiting buildings with poor heat resistance.