Rice husk ash (RHA) is an agricultural waste which is a pozzolanic material that can be blended with the cement for manufacturing concrete. Its use can reduce the environmental impact of the cement industry. The present study investigates the chemical and morphological nature of RHA and silica fume (SF). Both can be used to improve strength and durability properties of concrete. Particle size distribution, loss on ignition (LOI), X-ray diffraction analysis, scanning electron microscopic were conducted. The effect of replacement of cement 5%, 10% and 15% by weight with SF and RHA on compressive strength and workability has also been investigated for 32 MPa grade concrete blended with 30% Fly ash. The results show that concrete mixed with RHA had better strength than a similar mix with Silica Fume. RHA required additional amount of superplasticizer to improve the workability of concrete. In order to reduce the carbon footprint associated with cement industry, this paper gives satisfactory results to use RHA in sustainable construction.