Design precedents are available instances of architectural projects by high profile architects and designers, which can be studied and analyzed as knowledge resources for a given project. Developing a design knowledge based on a critical study of precedents will be referred to in this paper as Precedent-Based Knowledge. In all stages of designing, design reasoning based on precedents can save designers the time and effort needed to generate new design solutions from scratch. Starting with a precedent-based design model can enhance solving a new design problem by departing from a case in its entirety or by the partial borrowing of some of its features. A successful precedent-based design model seems to evolve from an efficient and properly presented precedent-based analysis model. Similarly, an efficient precedent-based analysis model is strongly related to an informative precedent-based evaluation model. In order to be of practical use, precedent-based analysis models should covey information inferred from precedents in well-structured and organized representations to enable designers to rapidly access desired data and effectively draw new information during the design synthesis process. Design knowledge gained from studying precedents is believed to help in the various design reasoning processes a designer may need. Previous experiences embedded in precedents help in understanding new situations and in projecting older solutions into new problems. As such, experience can be used when performing different tasks, both those that are repeated, and those that are new. Deriving emergent design products from precedents as a design strategy has its roots in various fields of knowledge. These include: (1) the theory of dynamic memory, (2) early studies of systematic design methods, (3) architectural typology, (4) using precedents for formulating formal composition principles, and finally (5) studies of decision making. The first includes the analogical use of memory which is concerned with storage and retrieval of the exemplars offered by design precedents or case studies. In this area, the process of using analogy in problem solving or what is called analogical reasoning is believed to play a key role in creative design. This paper, on one hand, focuses on typology of such knowledge-based elements and on the other hand tries to study a model to obtain applied knowledge from those precedents in order to evaluate their effect on design ideas creativity and new proposed solutions of the designers. Diverse types of application of design precedents were studied among 65students of Shiraz Art & Architecture University in their 4th semester of studying architectural design. The attendants were divided into 5 groups and each group was presented by a particular design precedent via a preferred survey model which was a fusion of Eilouti's and Lawson's models. Then the attendants were asked to generate their own new design solutions. The results revealed that using diverse precedents while incorporating an appropriate model to extract applied knowledge will lead the designers profoundly towards a more creative design solution. At the end, the paper proposes methods to enrich the extraction process of knowledge from design precedents in order to increase the creativity in the design process.