Current research on living and working spaces continues to strive to identify the most energy-efficient methods for heating and cooling, and many novel technologies have emerged from the research. One of the most promising, and the topic of this quantitative analysis, is the retrofitting of phase change materials (PCMs) into the walls of structures. Research has shown positive results, such as a reduced transfer of heat through walls, when PCMs are retrofitted into wall construction. The present research takes previously gathered data from test houses, built with typical North American framing, and simulates an additional fourteen test houses from the gathered data. The simulated houses consisted of a unique combination of walls retrofitted with and without PCM in them. The fourteen unique simulations allowed for seven metrics, such as max heat flux, time delays (start, peak, and end), total heat, heat flux average, and standard deviation, to be measured. Most of the measure indicated a positive correlation with the addition of PCM being retrofitted into a wall. From the results, the east, west and south walls emerged to be the most influential when it came to the seven measures, and it is recommended that at least one of these three walls be included when retrofitting buildings.