Abstract
Eco-design, sustainability and energy efficiency are emerging concepts that reflect the need to design new building solutions that are environmentally friendly and reduce material and energy consumption. Indeed, the probability of a massive climate change, capable of threatening the planet’s stability, is high if the current trend continues. The purpose of this study is to elucidate the main thermal insulation materials dominating the current market as well as their origins, strengths, and weaknesses. Additionally, the study identifies the criteria that make an insulator ideal and may be competitive in the near future as well as the direction of research in order to develop advanced materials. The results of the consulted studies reveal that there is no agreement on an ideal insulator that gather all the thermal insulation requirements. Each of the categories has its own weaknesses that should be addressed in the future to overcome. As well, super-insulators remain one of the most promising materials in this market, but they require more research in order to overcome some of the weaknesses that limit their insertion and production on a large scale. Ecological materials produced from natural fibers are currently far from being the candidates that can compete with super-insulators. Thus, considerable efforts are required to make these natural fibers able to dominate the construction market. Similarly, the comparison of the thermal conductivity of the four categories confirms that super-insulators are the most effective in reducing heat transfer through walls and through thinner layers as well. Finally, in addition to the ecological aspect, the thermo-physical and mechanical properties, and so on, the insulating materials must guarantee certain percentages of acoustic insulation.