the preliminary design document is a stage of engineering design, which is carried out after the construction project is approved. According to the relevant national laws, regulations and technical requirements, the preliminary design documents need to include architectural design, structural design, water supply and drainage design, electrical design and other professional design contents. The project budget estimate is an important basis for compiling the construction drawing budget, which evaluates the economy and feasibility of the project. Therefore, according to the relevant regulations, the preliminary design documents generally include the preparation of the project budget.
It should be noted that there may be some differences between different regions and different types of engineering projects. If you specifically aim at the provisions of a project or a region, you need to inquire and analyze the specific requirements of relevant engineering design documents.