During the coal-burning process, fly ash is produced as a by-product and disposal of this vast waste material is becoming challenge in the current environmental scenario. In the present work, metal oxide V2O5 with different weights (3% and 5%) of fly ash was utilized in presence of alkaline activators to lower the mullitization temperature below to 1000 o C for the development of new concrete approaches. The building composites were made by using sintered fly ash and alkaline activators at ambient temperature. The micro structural analysis (XRD, FESEM, EDX) of the composites reveals the formation of needle like nano sized mullite at 1000 o C. The durability and mechanical strengths tests including, compressive strength, flexural strength, split tensile strength, chloride ion permeability, water absorption and ultrasonic pulse velocity were conducted on the composites specimens. The experimental tests confirm the better strength and enhanced durability properties of the newly formed building composites. The study suggested a new methodology to utilize the waste material fly ash with vanadium oxide as an alternative cementitious materials for advanced durable building composites.