As-Built Drawings

Creating accurate and comprehensive as-built drawings requires a combination of surveying techniques, documentation methods, and digital tools. Here are several methods commonly used to create as-built drawings:

• Manual Measurements and Sketching: Begin by conducting a physical survey of the building, taking precise measurements of key dimensions, features, and structural elements using tape measures, laser distance meters, and other surveying tools. Record these measurements on paper or graph paper, sketching out floor plans, elevations, and cross-sections to represent the existing conditions of the building.
• Photogrammetry: Utilize photogrammetry techniques to capture detailed 3D models of the building’s exterior and interior using overlapping photographs. Specialized software processes these photographs to generate accurate measurements and spatial data, which can be used to create digital as-built drawings and models.
• Laser Scanning: Employ 3D laser scanning technology to capture precise measurements of the building’s geometry and features. Laser scanners emit laser beams to create point clouds, which are then processed into 3D models using software such as Autodesk Recap or Leica Cyclone. These models can be used to generate accurate as-built drawings and documentation.
• Archival Research: Consult historical records, building plans, and archival photographs to gather information about the building’s original design and subsequent modifications. Compare historical documentation with current conditions to identify changes and discrepancies that need to be documented in the as-built drawings.
• Mobile Mapping Systems (MMS): Use mobile mapping systems, such as vehicle-mounted LiDAR scanners or handheld devices equipped with GPS and LiDAR sensors, to capture detailed 3D data of the building’s exterior and surrounding environment. This method is particularly useful for large-scale projects or buildings with complex geometries.
• Total Station Surveying: Employ total station surveying instruments to accurately measure distances, angles, and elevations of building features. Total stations combine electronic distance measurement (EDM) with angular measurements to capture precise 3D coordinates,  which can be used to create As-Built drawings for small and large buildings .
• Building Information Modeling (BIM): Develop digital as-built drawings using Building Information Modeling (BIM) software such as Autodesk Revit or Trimble SketchUp. BIM allows for the creation of intelligent 3D models that incorporate detailed information about building components, materials, and systems, facilitating more efficient design, analysis, and documentation.
• Drone Surveying: Utilize drones equipped with high-resolution cameras and LiDAR sensors to capture aerial imagery and 3D point clouds of the building and its surroundings. Drone surveying enables rapid data collection and can provide valuable insights into the building’s condition and context.
• Field Verification and Validation: Conduct field verification and validation to ensure the accuracy of the collected data and as-built drawings. Verify measurements and dimensions on-site, cross-referencing with existing conditions and documentation to identify any discrepancies or errors.
• Collaborative Documentation: Foster collaboration between architects, engineers, surveyors, historians, and other stakeholders involved in the project to ensure that all relevant information and perspectives are incorporated into the creation of as-built drawings. Establish clear communication channels and documentation protocols to streamline the process and maintain consistency and accuracy throughout the project.

By leveraging these methods and techniques, restoration professionals can create accurate, detailed, and comprehensive as-built drawings that serve as invaluable resources for documenting historical structures, guiding restoration efforts, and preserving our building design heritage for future generations.