The built heritage in Algeria is invaluable but is now weakened by several factors, related on one side to the effects of time and natural factors and on the other to uncontrolled interventions. Although probably involuntary, these interventions are often due to a lack of knowledge of the building’s components, including its materials and construction techniques. Solutions are developed to overcome these problems, particularly through the use of computer tools, including databases and knowledge bases. In the Algerian context, to assist the heritage stakeholders in the decision-making process during the interventions on heritage buildings, a database focused on materials, namely a Digital Materials Library (DML), will be developed. Once completed, the latter will have capitalized on and centralized a significant amount of disparate data, which is necessary to avoid and reduce restoration errors. The Casbah of Algiers has been chosen as the first example of an application for the tool to be proposed. In this paper, the discussion will focus on the data collection stage of a study corpus of residential buildings located in the Casbah of Algiers, as well as the identification process of the building materials used, which will be included in the DML. This step is an important part of the methodological process of elaborating a DML that will be proposed at the end of this research. The residential building corpus study allowed the identification of three main material families, most common in the Casbah of Algiers and its surroundings. Simultaneously with this work, each material is being documented to propose a collection of potential and necessary recommendations for adequate use and intervention. Moreover, these material families will represent one of the content organization and presentation categories that will be suggested in the DML interface.