This study aimed at quantifying the impact of the reinforced standard for envelope insulation on heating and cooling energy consumption in a Korean detached house as well as at identifying the effect of regionally subdivided standards. For them, a series of simulations for application of the reinforced standard on respective walls, roof, floor, windows, and all envelopes were computationally conducted for a prototypical detached residential building. In addition, the subdivided standards were applied to each regions-central and southern regions, and the Jeju island. Analysis revealed that heat transfer through envelopes was the most significant source of building heat gain and loss; the reinforced standard effectively reduced heating energy consumptions, especially in central region; and the subdivided standards did not presented a clear difference in the amount of energy consumption for the southern region and the Jeju island, thus, a further study is required to investigate the necessity of regional subdivisions.