This paper intends to explore methods of constructing a design simulator. Two methodologies, approached differently, imitate the human design processes. The first component is an algorithmic method which has a cognitive model embedded. This cognitive model hypothesizes that human design has certain design logic applied. The design rationales are based on knowledge stored in a designer memory. Each time a similar design task is encountered, the same design procedures will be repeated for completion. What makes the results different are the design information used and sequences of processing it. A kitchen design using procedural algorithms is developed to simulate this design aspect. The second component simulates an intuitive design approach. Intuition is defined as design by rules of thumb, or heuristic design. This study investigated how to simulate an intuitive design process. The method involves building up a set of inductive rules symbolizing cultural aspects that need to be addressed in a design. A residential foyer design is the simulation task. The driving force is the heuristics. Results in this study have shown that there are many variables to include but impossible to capture and simulate any of the design processes, which are the reasons why studies in this area are difficult.