It is known that the increasing demand for cement production is linked to the increasing world population, and the rapid development of construction technology. As a result of these factors, cement plants are causing a massive environmental problem by emitting CO2 into the atmosphere. This significant air pollution may contribute to global warming. The search for alternative eco-friendly materials is an urgent need. Fly ash is a by-product in the form of powder produced by burning pulverised coal in power plants in huge quantities. Having no useful application, it is an organic waste, causing problems in landfilling. It is a pozzolanic material high in alumina and silica, which in the presence of water, acquires the cementitious properties of a renewable secondary cement-based material. When it is added to different types of binder, a new type of binder can be formed due to the mutual influence of fly ash on the nature and speed of the processes. The aim of the study was to develop a composition based on fly ash with a high content of free calcium oxide to replace cement with an alternative binder in the production of structural materials. For this, it was made a series of composite samples of different properties to obtain multilevel reinforcement. These samples showed high compressive strength (up to 90 MPa), indicating the synergistic effect of the composite components and their proper selection in building structures.