Dealing with issues of acquiring and accessing design knowledge in the conceptual stage of the design process is the focus of this research. This research starts by presenting a brief background about the limitations of the available energy-based CAAD tools. It then provides an illustration and description of the entire architecture of the conceptual model, identifies its different components and explains the relationships and interactions among these components. It identifies the necessary types of knowledge needed in this stage, such as general strategies, design guidelines, and rules of thumb, and develops an appropriate access structure for integrating the knowledge bases with the user interface. The developed structure incorporates a simple sketching tool that supports automatic creation of links between nodes of access and nodes of knowledge.