At the present stage, many large-scale construction activities are taking place in developing countries. Designers are paying a special attention of temperature to design of massive foundations which are necessary to accommodate design loads. While designing these massive foundations, the use of medium strength reinforced concrete such as grades C30, C35, and C40 is becoming a common practice. In case of South Asian countries, fly ash is currently used as the main cement substitute to control thermal cracking while designing medium-grade concrete by considering its benefits in engineering and economic nature. Even though the grade of the concrete and percentage of fly ash replacement are differed from project to project, a common temperature differential value of 200C based on American or European design codes is often used as a capping value to control early age thermal cracking. In this study, the influence of temperature differential on early-age thermal cracking risk, possible cracking location, the influence of supporting structure on the risk of cracking in mass footing construction are studied through numerical analysis for the rational design under hot weather conditions.