This study presents an innovative approach to thermal modeling of a solar container house in Algeria using DesignBuilder, focusing on enhancing its energy performance through targeted interventions. Despite being equipped with an intelligent control system for managing domestic appliances, the house exhibits several critical weaknesses in energy efficiency. We have identified three critical areas for improvement and proposed simple solutions for each: (1) Low thermal inertia and a short phase shift time lead to inadequate thermal comfort during the summer months. (2) The house is elevated on concrete stilts instead of having a ventilated basement, which prevents it from benefiting from the cooler nighttime air and the more stable temperatures of the ground. (3) Lack of effective shading elements to minimize solar gains through the glazing and the southern wall. Using dynamic simulation, we evaluated the energy gains achieved through modifications made to our structure. Renovating the building by adding a concrete layer and incorporating high thermal inertia phase change materials (PCMs) resulted in a 40% reduction in cooling demand and improved phase shift characteristics. Additionally, by implementing solar shading elements, we achieved a 56.6% reduction in solar gains through the windows, along with a decrease in cooling capacity by 1.5 kW. Replacing the stilts of the prefabricated house with a ventilated basement yielded significant benefits, resulting in reduced thermal gains through the floor and a decrease in cooling capacity by 3.3 kW. The solutions proposed are not only innovative but also simple and inexpensive. This affordability makes them accessible for implementation in Algeria, where budget constraints are often a significant barrier to energy efficiency improvements.