Multi-Materials in Architecture: Grigoriadis' main research area is multi-material design and the implications of functionally graded material use in architecture and construction. More specifically, his PhD thesis proposed a new methodology of designing with functionally graded materials using particle system element simulations. This method was used to design the connection of glazing to aluminium frame in a curtain wall envelope and concerned the whole process from beginning to end, of research, design, and fabrication of the connection. Theresulting original contribution of the thesis was a process model created in an existing simulation software that can be used in a standardlaptop computer to design with functionally graded materials. In addition to his PhD thesis, a recently awarded fellowship for Google in California, instigated a new research area relating to multi-material design, namely of the environmental benefits and embodied energy savings incurred by the use of these materials in buildings. The range of topics that the broader multi-material research agenda investigates include: advanced computational design and computational fluid dynamics simulations in architecture, multi-material or functionally graded material design, multi-colour and multi-material 3D printing and fabrication, generative design (topology optimisation) and embodied energy of multi-material building parts.

Epistemology of Computer Simulations in Architectural Design: On a theoretical level, a further research topic is the formulation of an appropriate epistemology(also known as the epistemology of computer simulations—EOCS) linked to the use of computer simulations to design with(computational blending). More specifically, this concerned the creation of a criteria framework for setting out, running, and evaluating the results of thesimulations.

Cognitive Theory (Material Engagement Theory and Conceptual Blending): Drawing from Lambros Malafouris' Material Engagement Theory (MET) and Turner and Fauconnier's Conceptual Blending Theory, another main research investigation is in the cognitive processes taking place when designing with graded materials in the computer. Additionally, the question of authorship and agency in the design process is analysed through MET in order to rethink the wider anthropocentric notion of form imposition on materials.