This study investigates the limitations of localized heating in a single-story dwelling, using a validated computational fluid dynamics (CFD) model to analyze thermal stratification and its impact on occupant comfort. A comparative evaluation of turbulence models (k-ε and k-ω SST) and equations of state (Soave–Redlich–Kwong and Peng–Robinson) identified the k-ω SST model with the Soave–Redlich–Kwong equation as the most accurate and computationally efficient combination for capturing temperature gradients and achieving rapid convergence. Experimental validation demonstrated strong agreement between simulated and measured temperature profiles, confirming the model’s reliability. The results highlight a fundamental trade-off between localized thermal comfort and overall indoor temperature uniformity in conventionally heated spaces. While localized heating enhances comfort near the heat source, it generates vertical temperature disparities exceeding acceptable comfort thresholds at greater distances. Specifically, at 3 m from the heat source, the temperature difference between ankle and head height reached 6 °C, surpassing the 4 °C limit recommended by ASHRAE-55 for standing occupants. These findings underscore the need for alternative heating solutions that prioritize uniform heat distribution, energy efficiency, and optimized ventilation to improve indoor thermal comfort in residential buildings. This study provides critical insights to help develop and implement sustainable heating strategies and the design of energy-efficient dwellings.