This paper presents the investigations of the environmental advantages of low carbon composite gypsum binders for building applications. The impact of ultrafine zeolite additive on the physico-mechanical properties and hydration processes of composite gypsum binders has been investigated. The modification of gypsum pastes by polycarboxylate type superplasticizer results in the radical change in the formed microstructure of composite gypsum binders. The obtained results are essential for further design and development of new types of gypsum composites with an increased water resistance.