The thermal insulation envelope is a major challenge whose heating and cooling consumption can be reduced. The use of ecologic materials, as a recycled material, to improve a comfort and take control of an environmental impact. The aim of this research is not only to develop sustainable designs in the context of hot and dry climates conditions, but also to devise innovative thermal insulation systems using recycled fibers materials, in an attempt to increase thermal comfort. In two methods; Experimental and numerical, we are evaluating thermal characteristics, energy efficiency and comfort level achieved by these materials. Apart from that, the thermal performance and energy saving results are consistent with those set in the scientific literature. However, fire resistance and Lifecycle Cost Analysis of the material is less strong, which indicates that the recycled material developed possesses interesting thermal performance, worthy of use in building insulation in Algeria. Key Findings of this work is Recycled materials (polystyrene, fiber wool, cellulose) offer viable alternatives to traditional insulation. These materials enhance thermal comfort by stabilizing indoor temperatures and reducing energy demand. Sustainability benefits include reduced landfill waste and lower embodied energy. The result obtained reflects enhanced performance using re-cycled fibers such as wood fibers, and a decrease in energy usage by 56%, as opposed to the use of natural resources such as cellulose 65% and 50% when using polystyrene.