This paper presents new approaches of reusing fly ash generated in thermal power plant in the manufacturing of cellular concrete. Therefore, the research novelty is to make a meaningful utilization of fly ash as a binder to improve cellular concrete properties. The study has showed that fly ash has pozzolana properties which can boost up mechanical strength, thermal insulation and durability of cellular concrete, which may lead to obtain high quality final product in comparison with traditional building materials. Moreover, utilization of fly ash facilitates both reduction of heat conductivity and reduction of concrete density. This properties make cellular concrete resistant to heat transfer. Physical, mechanical and thermal tests have been carried out during research. The study of type of dependence between cellular concrete durability and its mix design has a valuable practical importance since it supports to reach maximum durability in lightly consumption of binder. We may conclude that the utilization of fly ash in the amount of 295 kg/m3, while the cellular concrete density is equal to 600 kg/m3, allows to solve a number of problems such as damaging of human health and environment pollution and to develop energy efficient cellular concrete. The research included the results of cellular concrete mix flowability, density, moisture, strength properties and concrete grade equal to B2,5-B3,5 with a density of porous ash concrete equal to 600 kg/m³. The natural wollastonite was utilized in this research as a reinforcing material to improve the tensile stregnth of cellular concrete.