In the realm of construction, particularly in residential settings, a significant portion of energy consumption is attributed to the provision of essential thermal comfort through heating and air conditioning systems. To address and optimize this energy usage while mitigating excessive consumption, thermal insulation stands out as an effective technology for achieving desired indoor comfort levels. The core concept behind thermal insulation is the careful installation of insulating materials selected for their energy-efficient properties, thereby minimizing heat loss or gain and enhancing energy self-sufficiency. This paper aims to offer a comprehensive review of the existing literature concerning sustainable thermal insulation solutions derived from locally available and abundant natural fibers, specifically tailored for the construction industry. Additionally, it explores the evolution of various forms of natural fiber-reinforced polymer composites. The findings from various research efforts confirm the significant advancements achieved in the field of building insulation through the utilization of locally sourced natural fibers.