Difference between CD Sets and Shop Drawings

Before starting any construction project on site, it is first visualized by a series of sketches developed into drawings that precisely describe the project’s scope, intent, and nature. These sets of drawings are developed stage by stage and are used by various and wide groups of people for the successful completion of the project.

Generally, there remains a question on what is the actual difference between shop drawings and Construction drawing aka CD sets. This blog covers the differences between these sets of drawings.

What are CD sets?

Firstly let’s talk about CD sets, also known as Construction Documentation Sets. These drawings are prepared by architects/ engineers who detail the design that represent the overall design intent and serves as a roadmap for the entire construction project. It comprises a set of drawings to understand the dimensions of the project and details needed to understand the basic nature of these design elements.

In-depth and detailed, the CD set comprises a set of drawings from the survey plan to the schedules of manufacturing elements. Breaking the list, the set includes:

  • Survey drawings
  • Site plan and existing condition/ demolition plans (if any structure exists prior to construction)
  • Structural plans
  • Floor plans and roof/ terrace plans
  • Elevations
  • Interior elevations
  • Building and wall sections
  • Plan details
  • Mechanical-electric/lightning, plumbing and
  • Schematic drawings for all the building components such as doors and windows and schedules

What are Shop drawings?

Shop drawings are a set of detailed drawings needed with the CD set to complete the project. Also known as fabrication drawings, they include all the details to illustrate how a specific element will be fabricated thereby providing all the needed details. Shop drawings are mainly used to create drawings for the purposes of fabrication, joinery, assemblies, and installations and their detail drawings. While MEP Shop Drawing Services provide help for MEP systems, these drawings are also created for various elements such as structural and steel works, precast, millwork, and other details which are to be taken into account on-site.

Shop drawings include:

  • Identification of the component with tags and dimensions
  • Information about interferences, neighbouring components, and tags (Level & Materials)
  • Coordinates for the site’s location and component measurements
  • The location and dimensions of the openings (found in structural shop drawings with MEP openings)
  • The sequential order of each shop drawing
  • Needs for Clearance, Assembly Information
  • Project name, number, subcontractor names, general information, acronyms, and legends are included in the title block.
  • Dates of the first drawing submission and revisions, along with descriptions
  • Fabrication guidelines Data on erection and installation

Construction drawings are also called bid drawings as these drawings are used by contractors to place the bids. Once the project is finalized shop drawings are done which take the actual field conditions into consideration and all the other details mentioned above. Both these set of drawings are equally needed to complete a project.

Conclusion

Where the CD set serves the primary purpose of construction, shop drawings are the backbone of the fabrication and installation process. For the successful completion of any construction project, Construction Documentation Services and MEP shop drawings go hand in hand while serving their purpose at the needed stage of construction and it should be ensured that these drawings are made error-free to achieve the intended results.

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