In the last decades, the EPS (expanded polystyrene) and the XPS (extruded polystyrene) have become the most frequently used thermal insulation. Furthermore, the XPS has step resistant thermal insulation with higher strength. Nowadays in our current economic situation, the circular economy plays a significant role. That means we need to intend making a product that becomes waste as late as possible. Instead of a product, the goal is to return it to the economy as a basic material for a new product. Instead of generating waste, a new chance must be given by reusing it. Based on that consideration, our research work was in producing reinforced EPS material, which has the physical and thermal properties at least, as the XPS is much more expensive to produce. For reinforcement, materials have been chosen, in terms of its current life cycle, considered as product or waste. The first choice were plastic straws and cutleries that will be redrawn from the market. The next additives were renewable materials from agriculture like straws of wheat. It is essential for this research work to map the possible raw materials, i.e., EPS and XPS. The article collects the properties of the EPS and XPS and the related simulation methods that can be found in the literature.