ERDCSR-24-3_AECStandard_R6_2.pdf

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The CAD/BIM Technology Center for Facilities, Infrastructure, and Environment

A/E/C Computer-Aided Design (CAD) Standard Release 6.2

In fo rm at io n

Te ch no lo gy L ab or at or y

Stephen Spangler July 2024

Distribution Statement A. Approved for public release: distribution is unlimited.

The U.S. Army Engineer Research and Development Center (ERDC) solves the nation’s toughest engineering and environmental challenges. ERDC develops innovative solutions in civil and military engineering, geospatial sciences, water resources, and environmental sciences for the Army, the Department of Defense, civilian agencies, and our nation’s public good. Find out more at www.erdc.usace.army.mil.

To search for other technical reports published by ERDC, visit the ERDC online library at https://erdclibrary.on.worldcat.org/discovery.

http://www.erdc.usace.army.mil/ https://erdclibrary.on.worldcat.org/discovery

The CAD/BIM Technology Center for Facilities, Infrastructure, and Environment

ERDC/ITL SR-24-3

July 2024

A/E/C Computer-Aided Design (CAD) Standard Release 6.2

Stephen Spangler US Army Engineer Research and Development Center (ERDC) Information Technology Laboratory (ITL) 3909 Halls Ferry Road Vicksburg, MS 39180-6199

Final Special Report

Distribution Statement A. Approved for public release: distribution is unlimited.

Prepared for Headquarters, US Army Corps of Engineers Washington, DC 20314-1000

Under Civil Direct Funding

ERDC/ITL SR-24-3 ii

Abstract The A/E/C Computer-Aided Design (CAD) Standard has been developed by the CAD/Building Information Modeling (BIM) Technology Center for Facilities, Infrastructure, and Environment to eliminate redundant CAD standardization efforts within DoD and the Federal Government. This manual is part of an initiative to develop a nonproprietary CAD standard that incorporates existing industry, national, and international standards and to develop data standards that address the entire life cycle of facilities within DoD.

The material addressed in the A/E/C CAD Standard includes level/layer assignments, digital file naming, and standard symbology. The CAD/BIM Center’s primary goal is to develop a CAD standard that is generic enough to operate under various CAD software packages (such as Bentley’s MicroStation and Autodesk’s AutoCAD) while incorporating existing industry standards when possible.

While this Standard encompasses many CAD concepts and practices, it is not intended to limit the capabilities of other advanced modeling software.

Ultimately, a BIM / Civil Information Modeling standard will be developed to standardize the additional capabilities of other software.

DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes.

Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products.

All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR.

ERDC/ITL SR-24-3 iii

Contents Abstract ................................................................................................................................................... ii

Figures and Tables .................................................................................................................................. v

Preface .................................................................................................................................................... vi

1 Introduction

1.1 Background

1.2 United States National CAD Standard

1.3 Objectives

1.4 Approach

1.5 Scope

1.6 Target Systems

1.7 Design Applications and Other Applications

1.8 Coordination with Design Agent

1.9 Additions/Revisions

2 CAD File Organization

2.1 CAD File settings

2.1.1 Available Design Area

2.1.2 File Accuracy (Units)

2.1.3 International Feet versus Survey Feet

2.1.4 Origin (Global Origin)

2.2 CAD File Contents

2.2.1 Modeling Area

2.2.2 Drawing Area

2.2.3 Sheet Area

2.3 CAD File Types

2.3.1 Model Files

2.3.1.1 Border Sheet Model Files

2.3.1.2 Raster References

2.3.2 Sheet Files

2.4 CAD File Naming Conventions

2.4.1 Project Code

2.4.2 Discipline Designators

2.4.3 Model File Naming

2.4.3.1 Modeling Area File Naming Convention

2.4.3.2 Drawing Area File Naming Convention

2.4.4 Sheet File Naming Convention

2.4.4.1 Adding a Sheet

2.4.4.2 Coordinating Sheet Identifiers

3 Graphic Concepts

3.1 Presentation Graphics

3.1.1 Line Widths

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3.1.2 Line Types/Styles

3.1.3 Line Color

3.1.4 Plotting

3.1.5 Screening/Dithering

3.2 Text

4 Level/Layer Assignments

4.1 Level/Layer naming convention

4.2 Level/Layer Assignment Tables

4.2.1 General Levels/Layers

4.2.2 Status (Phase) Levels/Layers

5 Standard Symbology

5.1 Introduction

5.2 Symbology Resources

5.2.1 Cells/Blocks

5.2.2 Line Types/Styles

5.3 Downloadable Resources

6 Conclusion

Bibliography

Appendix: Model File Level/Layer Assignment Tables

Abbreviations

Report Documentation Page

ERDC/ITL SR-24-3 v

Figures and Tables Figures

2-1. 2D workflow 2-2. 3D workflow 2-3. Modeling area file naming convention 2-4. Drawing area file naming convention 2-5. Sheet file naming convention 2-6. Supplemental drawing designator 2-7. Typical border sheet title block with sheet identification block 3-1. Predominant line types/styles 4-1. Typical levels/layers contained in a sheet file 4-2. Level/layer naming format 4-3. Level/layer assignment table

Tables

2-1. Discipline designators 2-2. Drawing area file types discipline designators 2-3. Sheet file discipline designators 2-4. Sheet type designators 3-1. Comparison of line widths 3-2. Basic colors 3-3. Screened colors 4-1. Status (Phase) codes

ERDC/ITL SR-24-3 vi

Preface This study was conducted for Headquarters, US Army Corps of Engineers (HQUSACE), under Civil Direct Funding. The technical monitor was Mr.

Jason Fairchild, Headquarters.

The work was performed by the Computer-Aided Design/Building Information Modeling (CAD/BIM) Technology Center of the Software Engineering and Informatics Division (SEID), US Army Engineer Research and Development Center–Information Technology Laboratory (ERDC-ITL). At the time of publication, Mr. Joseph Farrar was chief, CAD/BIM; Mr. Quincy Alexander was division chief; and Dr. Robert M.

Wallace was technical director. The acting deputy director of ITL was Ms.

Amie J. Burroughs, and the acting director was Dr. Jackie S. Pettway.

The Center acknowledges the support of Mr. Jason Fairchild, HQUSACE.

Special thanks go to the following USACE staff for their technical expertise in the development and review of this document: Mr. Roger Fujan, US Army Engineer District, Walla Walla; Mr. Gerald Piotrowski, US Army Engineer District, Louisville; and Mr. Brian Baker, US Army Engineer District, Pittsburgh.

COL Christian Patterson was the commander of ERDC, and Dr. David W.

Pittman was the director.

ERDC/ITL SR-24-3 1

1 Introduction

1.1 Background

The Architecture, Engineering, and Construction (A/E/C) CAD Standard has been developed by the Computer-Aided Design/Building Information Modeling (CAD/BIM) Technology Center for Facilities, Infrastructure, and Environment (hereafter referred to as the Center) to eliminate redundant standardization efforts within the DoD and the Federal Government. This manual is part of an initiative to develop a nonproprietary CAD standard that incorporates existing industry, national, and international standards.

Additionally, this standard is intended to support the entire life cycle of facilities within the DoD. This report supersedes A/E/C CAD Standard, Release 6.1 (ERDC/ITL TR-19-7).

The immediate benefits of CAD standards are the following:

• Consistent CAD products for customers

• Uniform requirements for architecture-engineering deliverables

• Sharing of products and expertise

Recognizing such potential benefits, each of the DoD agencies independently initiated efforts to establish CAD standards in the late 1980s. In 1989, the Air Force Logistics Command released the Architectural and Engineering Services for Computer-Aided Design and Drafting (CADD) Implementation within Air Force Logistics Command.

Headquarters, US Army Corps of Engineers (USACE), in 1990 published Engineer Manual 1110-1-1807, Standards Manual for U.S. Army Corps of Engineers Computer-Aided Design and Drafting (CADD) Systems. In 1993, the Naval Facilities Engineering Command (NAVFAC) distributed its Policy and Procedures for Electronic Deliverables of Facilities Computer-Aided Design and Drafting (CADD) Systems.

To consolidate these efforts into a single standard, the Center was tasked to develop standards for the A/E/C disciplines. This manual presents the Center’s continuing effort at standardizing CAD requirements for A/E/C design and construction documents.

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1.2 United States National CAD Standard

In 1995, the combined resources of the Center, the American Institute of Architects (AIA), the Construction Specifications Institute (CSI), the United States Coast Guard, the Sheet Metal and Air Conditioning Contractors National Association (SMACNA), the General Services Administration (GSA), and the National Institute of Building Sciences (NIBS) Facility Information Council began to develop a single CAD standard for the United States. Working together, these organizations agreed to develop an integrated set of documents that collectively would represent the United States National CAD Standard (NCS).

The two main NCS documents referenced within the A/E/C CAD Standard are the following:

Uniform Drawing System The Construction Specifications Institute 123 North Pitt Street, Suite 450 Alexandria, VA 22314

AIA CAD Layer Guidelines The American Institute of Architects 1735 New York Avenue, NW Washington, DC 20006-5292

Each of these documents is available as part of the NCS. Additional information on the NCS, as well as how to purchase a copy, can be obtained from

National Institute of Building Sciences 1090 Vermont Avenue NW, Suite 700 Washington, DC 20005-4905 https://www.nibs.org https://www.nationalcadstandard.org/

1.3 Objectives

The objective of the A/E/C Standards (i.e., A/E/C CAD Standard and A/E/C Graphics Standard) is to aid in the documentation of design intent to be consistently, efficiently, and effectively transmitted through the https://www.nibs.org/

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construction phase to operations and maintenance (O&M) and back to design for future work.

1.4 Approach

The approach chosen to respond to A/E/C community comments and feedback entailed reviewing their concerns and recommendations. If the comment was from a purely personal preference standpoint, it was disregarded. If the comment proposed an object opportunity for improvement, a workaround was determined on how to best resolve the issue while still maintaining the intent of industry standards. A Frequently Asked Questions (FAQ) page was established to document the interim solutions. This document updates the A/E/C Standards to incorporate those solutions.

The intent of this document is to embrace the National CAD Standard while providing more guidance and clarifying areas of misunderstanding.

This document will not cover every circumstance encountered in drawing production. There may be specialized instances where it will be up to the site to develop internal best practices.

1.5 Scope

This manual provides guidance and procedures for preparing CAD products within the DoD. Chapters 2–5 of this manual address topics such as presentation graphics, level/layer assignments, digital file naming, and standard symbology. Appendix A contains tables on model file level/layer names.

1.6 Target Systems

This standard does not target any specific CAD system or software but does specifically target CAD workflows. To ensure successful translations among CAD applications, certain system-specific characteristics were considered and the standard adjusted accordingly. During the preparation of the standard, certain baseline decisions were made:

• The standard must be applicable to the latest release of commercially available CAD packages. AutoCAD and MicroStation were chosen based on their prevalence within DoD.

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• The standard is based on CAD applications that utilize level/layer names and external reference files.

1.7 Design Applications and Other Applications

Numerous design applications have been developed to run on top of or alongside basic CAD engines. These applications can be used by designers to generate graphics inside CAD files.

Document management systems that contain attributes or metadata for individual files and have such features as attribute exchange are becoming standard tools for management of digital files. Use of these systems to store searchable metadata for files is encouraged.

1.8 Coordination with Design Agent

With all the complexity and options currently available, it becomes vitally important to coordinate the fundamental aspects of design. Each project should have an initial discussion and agreement between the designer and customer on topics such as: design software, review software, output file format(s), and so on.

1.9 Additions/Revisions

This Standard is intended to be neither static nor all inclusive. Suggestions for improvements are strongly encouraged so that subsequent updates will reflect the input and needs of the users.

Recommendations or suggested additions should be sent by email to CADBIM@usace.army.mil.

mailto:CADBIM@usace.army.mil

ERDC/ITL SR-24-3 5

2 CAD File Organization

2.1 CAD File settings

2.1.1 Available Design Area

The two most extensively used CAD applications within the DoD, AutoCAD and MicroStation, both provide for a design area with nearly infinite range in each positive and negative axis (x,y,z).

2.1.2 File Accuracy (Units)

CAD systems allow the designer to work in real-world units. The most common units are feet:inches, survey feet:hundredths of survey feet (or thousandths), and meters:millimeters.

2.1.3 International Feet versus Survey Feet

Many sites must contend with the initial question as to whether a particular project is designed using international feet or survey feet. In some states, it is specified by statute that units of measure for grid coordinates must be either international feet or survey feet. The two units are defined as follows:

• International feet: 1 ft = 0.3048000 m.

• US survey feet (SF): 1 SF = 1,200/3,937 m.

Note: At the time of the revision of this document, the US survey foot is scheduled to be deprecated by the National Institute of Standards and Technology (NIST) and the National Geodetic Survey (NGS). Be sure to check with the issuing agency for required coordinate systems and units.

Note: If a drawing has already been created using international feet, changing the master units to survey feet will not automatically scale all elements in the drawing to survey feet. Also, survey feet and international feet should not be mixed in similar disciplines due to horizontal shifts over large distances.

2.1.4 Origin (Global Origin)

Positioned within every digital drawing file is an origin (“global origin” in MicroStation and “origin” in AutoCAD). The origin of a drawing file is

ERDC/ITL SR-24-3 6

important because it serves as the point of reference from which all other elements are located. Origins are typically defined in a drawing file by the Cartesian coordinate system of x, y, and z.

The benefit of standardizing the location of the origin of a drawing is most notable in the use of external reference files (see Section 2.3.1.1). A standardized origin is also helpful when translating files between CAD applications. The recommended global origin for files in both AutoCAD and MicroStation drawings is x = 0, y = 0, and z = 0.

2.2 CAD File Contents

CAD files contain various types of designs (2D or 3D) used to generate construction plans. The contents of these files will vary depending on the design authoring software but typically contain the following types of areas: 3D modeling, 2D drawing, and/or the 2D sheets (see Sections 2.2.1, 2.2.2, and 2.2.3). Depending on project requirements, project size, or design authoring software, the CAD files for a project may be organized by file use (e.g., project, discipline, modeling/drawing/sheet area type, file extension, etc.) and contain one or multiple types of areas (Figures 2-1 and 2-2).

Note: A MicroStation design file (.dgn) may have multiple modeling areas (design models) and multiple drawing areas (drawing models), while an AutoCAD design file (.dwg) will have only one modeling area or drawing area (model SPACE). Both MicroStation and AutoCAD may contain multiple sheet areas (MicroStation:Sheet Models, AutoCAD:Layouts/Paper Spaces).

ERDC/ITL SR-24-3 7

Figure 2-1. 2D workflow.

ERDC/ITL SR-24-3 8

Figure 2-2. 3D workflow.

ERDC/ITL SR-24-3 9

2.2.1 Modeling Area

The modeling area is where the 3D representation of physical components of a design (e.g., terrains, roads, curbs, columns, walls, windows, ductwork, piping, etc.) are drawn at full size (see Figure 2-2). Annotation is typically used sparingly in the modeling area to avoid text being misinterpreted as drawing content in alternate views.

2.2.2 Drawing Area

The drawing area is where the 2D graphical representation of physical components of a design are drawn at full size along with any annotation items (see Figures 2-1 and 2-2). Drawing areas can be generated either by placing graphics or by cutting views from modeling areas. Drawing areas include items such as plans, sections, elevations, and details.

2.2.3 Sheet Area

The sheet area is where views of the modeling areas and/or drawing areas are assembled to create a digital representation of the full-size plotted sheet. The sheet area contains a reference to the border sheet at 1:1. The addition of sheet-specific information (e.g., sheet annotation, symbols, sheet notes, etc.) completes the construction of the sheet area (see Figures 2-1 and 2-2).

2.3 CAD File Types

A CAD file is a container of the areas documented above. The CAD file types are model files and sheet files. It is important to name files appropriately so that model and sheet files can be easily distinguished.

2.3.1 Model Files

Model files contain modeling areas and/or drawing areas. Model files are developed or assembled prior to creation of sheet files. The components contained within a model file may be referenced by other models. Each reference shall have a unique name or logical description describing what is being referenced.

Referencing digital drawing information makes changes readily apparent to all design disciplines. This real-time access to the work of others

ERDC/ITL SR-24-3 10

ensures accuracy and consistency within a set of drawings and helps promote concurrent design efforts.

Note: Never bind/merge external references into the sheet areas since that will duplicate linework and increase the amount of work required to make future revisions.

2.3.1.1 Border Sheet Model Files

Border sheets are drawing areas in model files externally referenced by all disciplines to create sheet areas. This model file contains border linework, the title block, and project-specific symbols and text. All disciplines shall use the same border sheet within a project (for more information on border sheets, see the A/E/C Graphics Standard).

2.3.1.2 Raster References

Although raster imagery is not accurate, it allows for the reader to relate the design linework to real world objects. For interoperability, the most common raster file types referenced are TIF, JPG, and PDF. Raster file names shall conform to the model file naming convention with a model file type of “IG” (e.g., (Project Code)C-IG(User Defined).tif/jpg/pdf).

Raster File Type uses:

• GeoReferenced TIF: Best for aerial photographic imagery, maps, and drawings where the image is referenced under linework to add clarity.

• JPG: Best for nonaerial photographic imagery used for depicting existing conditions referenced to sheets.

• PDF: Best for historic drawings used as background images.

Note: It is suggested that MrSID files are not directly referenced. The files are extremely large and unwieldy to manage in a CAD/BIM / civil information modeling (CIM) environment. It is recommended that the MrSID image be clipped, resampled, and saved as a georeferenced TIF file. The smaller file size allows the software to open faster and plot more efficiently.

2.3.2 Sheet Files

A sheet file is a file that contains a sheet area or multiple sheet areas. A sheet file is a ready-to-plot CAD file. Sheet files may also contain drawing

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area(s) that have annotation that is appropriate for the sheet area that is referencing it.

2.4 CAD File Naming Conventions

Naming conventions for CAD files allow users to determine the contents of a file without opening it. They also provide a convenient and clear structure for organizing CAD files within a project directory.

Spaces are not allowed in any CAD filename. An underscore (_) or CamelCase may be used in lieu of a space, or a hyphen (-) may be used as a separator.

2.4.1 Project Code

The CAD file naming conventions require a Project Code (1 to 20 characters) at the beginning of the filename. The Project Code shall be identified at the start of each project to ensure consistent filenames within that project. Some examples of Project Codes include:

• the official agency project number and

• the project number defined by the contract issuing agency CAD manager for their record system.

The purpose of a Project Code is to indicate which project a CAD file is associated with.

When deciding on a standard file naming convention, the user might consider the use of a special character such as an underscore (_) (as part of the 20-character Project Code) at the beginning of the model filename so that model files are grouped together.

When a project includes multiple structures, features, or options, it is important to identify each file with the appropriate feature. This should be done as a part of the Project Code. For example, a model file for project P123 and building 2 could use a Project Code of _P123-Bldg2.

2.4.2 Discipline Designators

The NCS states that a Discipline Designator “denotes the category of subject matter contained on the specified layer.” However, this denotation leaves this type of designator open ended, resulting in Discipline

ERDC/ITL SR-24-3 12

Designators that are usually subsets of other disciplines. For example, Distributed Energy (which has the Discipline Designator “W” in the NCS) is typically shown in disciplines such as Mechanical or Electrical. To prevent the use of Discipline Designators where it is unclear what should be included within the “category of subject matter,” only the Discipline Designators shown in Table 2-1 shall be used.

Table 2-1. Discipline designators.

Discipline Designator

General G

Hazardous materials H

Survey/Mapping V

Geotechnical B

Civil C

Landscape L

Structural S

Architectural A

Interiors I

Fire protection F

Plumbing P

Mechanical M

Electrical E

Telecommunications T

Resource R

Other disciplines X

Operations O

2.4.3 Model File Naming

There are two different types of model files: modeling area files and drawing area files. The primary difference between these two types is that modeling areas are typically used to portray 3D and drawing areas are used to portray 2D. The NCS’s model file naming convention primarily focuses on 2D drawing practices and does not provide guidance for modeling area file types.

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2.4.3.1 Modeling Area File Naming Convention

The modeling area file naming convention (Figure 2-3) has three mandatory fields, and the fourth is optional. All fields must be in the correct sequence.

Following the Project Code field, the first two-character field represents the Discipline Designator. The allowable characters for the Discipline Designator are listed in Table 2-1. The second character of the Discipline Designator field is typically a hyphen (-), but files may contain multiple discipline models so the second character may continue listing disciplines located within the file. If there are more than two disciplines, continue utilizing the main feature field. The next 8-character (maximum) field represents the main modeling feature of the file (e.g., wall, bracing, corridor, etc.). The final optional user-definable 15-character (maximum) field is available to further describe the file contents.

It is recommended that the model area file naming schema be documented and be consistent for each project.

Figure 2-3. Modeling area file naming convention.

Note: Although Revit can contain many different area types within one file, it is recommended that users use the modeling area file naming convention for Revit (.RVT) files.

2.4.3.2 Drawing Area File Naming Convention

The drawing area file naming convention (Figure 2-4) has three mandatory fields, and the fourth is optional. All fields must be in the correct sequence.

ERDC/ITL SR-24-3 14

Following the Project Code field, the first 2-character field represents the Discipline Designator. The allowable characters for the first character in the Discipline Designator are listed in Table 2-1. The second character of the Discipline Designator field is always a hyphen (-). The next two-character field represents the Drawing Area File Type (NCS Model File Type) (Table 2-2). The final field is a 10-character (maximum) user-definable field.

Figure 2-4. Drawing area file naming convention.

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Table 2-2. Drawing area file types discipline designators.

Discipline Code Definition

General BS Border sheet

General CS Cover sheet

General IG* Raster imagery (scanned and photographic)

General KP Key plan

Hazardous materials DT Detail

Hazardous materials EL* Elevation

Hazardous materials IG* Raster imagery (scanned and photographic)

Hazardous materials LG* Legend

Hazardous materials PP Pollution prevention plan

Hazardous materials PR Profile

Hazardous materials QP* Equipment plan

Hazardous materials SC Existing section

Hazardous materials XD* Existing/Demolition plan

Survey/Mapping AL Existing airfield lighting plan

Survey/Mapping CP Existing communication system plan

Survey/Mapping EU Existing electrical utilities plan

Survey/Mapping HP Existing hydrographic survey and mapping plan

Survey/Mapping HT Existing HTCW Utilities Plan

Survey/Mapping IG* Raster imagery (scanned and photographic)

Survey/Mapping LG* Legend

Survey/Mapping PB Property boundary

Survey/Mapping PP* Plan and profile

Survey/Mapping PR Existing profile

Survey/Mapping SC Existing section

Survey/Mapping SV Survey and mapping plan

Survey/Mapping UP Existing utilities plan

Geotechnical DT Detail

Geotechnical IG* Raster imagery (scanned and photographic)

Geotechnical JP Joint layout plan

Geotechnical LB Boring log

Geotechnical LG* Legend

Geotechnical PV Pavement site plan

Geotechnical SC Existing section

Geotechnical SH* Schedule

Geotechnical SI Subsurface investigation plan

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Table 2-2 (cont.). Drawing area file types discipline designators.

Discipline Code Definition

Civil AF Airfield plan

Civil BR Beach renourishment plan

Civil DT Detail

Civil EL Elevation

Civil ER Eco-restoration plan

Civil FC Flood control plan

Civil GP Grading plan

Civil IG* Raster imagery (scanned and photographic)

Civil IP* Installation plan / base map

Civil JP Joint layout plan

Civil KP* Staking plan

Civil LG* Legend

Civil NG Navigation/dredging plan

Civil PL* Project location map

Civil PP* Plan and profile

Civil PR Profile

Civil SC Section

Civil SH* Schedule

Civil SP Site plan

Civil TS Transportation site plan

Civil UP Utilities plan

Civil XD* Existing/demolition plan

Landscape DT Detail

Landscape EL* Elevation

Landscape IG* Raster imagery (scanned and photographic)

Landscape IP Irrigation plan

Landscape LG* Legend

Landscape LP Landscape plan

Landscape SC* Section

Landscape SH* Schedule

Landscape XD* Existing/demolition plan

Structural 3D Isometric/3D

Structural BP Bridge plan

Structural CP* Column plan

Structural CW Misc. small civil works structures

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Discipline Code Definition

Structural DT Detail

Structural EL Elevation

Structural EP Enlarged plan

Structural FC Flood control structures

Structural FN Foundation plan

Structural FR Framing plan

Structural IG* Raster imagery (scanned and photographic)

Structural LD Locks and dams plan

Structural LG Legend

Structural SC Section

Structural SH* Schedule

Structural XD* Existing/demolition plan

Architectural 3D* Isometric/3D

Architectural AC Area calculations/occupancy plan

Architectural CP Reflected ceiling plan

Architectural DT Detail

Architectural EL Elevation

Architectural EP* Enlarged plan

Architectural FP Floor plan

Architectural IG* Raster imagery (scanned and photographic)

Architectural LG* Legend

Architectural QP Equipment plan

Architectural RP Roof plan

Architectural SC Section

Architectural SH* Schedule

Architectural XD* Existing/demolition plan

Interiors 3D* Isometric/3D

Interiors DT Detail

Interiors EL Elevation

Interiors EP* Enlarged plan

Interiors FL Floor patterns

Interiors IG* Raster imagery (scanned and photographic)

Interiors LG* Legend

Interiors QP* Equipment plan

Interiors RP Furniture plan

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Discipline Code Definition

Interiors SC* Section

Interiors SH* Schedule

Interiors SP Signage placement plan

Interiors WP System furniture plan

Interiors XD* Existing/demolition plan

Fire protection 3D* Isometric/3D

Fire protection DG* Diagram

Fire protection DT Detail

Fire protection FA Fire alarm/detection plan

Fire protection FP Fire suppression plan

Fire protection IG* Raster imagery (scanned and photographic)

Fire protection LG* Legend

Fire protection LP Life safety plan

Fire protection SC* Section

Fire protection SH* Schedule

Fire protection XD* Existing/demolition plan

Plumbing 3D* Isometric/3D

Plumbing DG Diagram

Plumbing DT Detail

Plumbing EL* Elevation

Plumbing EP* Enlarged plan

Plumbing IG* Raster imagery (scanned and photographic)

Plumbing LG* Legend

Plumbing PP Piping plan

Plumbing QP* Equipment plan

Plumbing SH* Schedule

Plumbing XD* Existing/demolition plan

Mechanical 3D* Isometric/3D

Mechanical DG Diagram

Mechanical DT Detail

Mechanical EL Elevation

Mechanical EP* Enlarged plan

Mechanical HP HVAC plan

Mechanical HS Hydraulic systems

Mechanical HT HTCW utilities plan

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Discipline Code Definition

Mechanical IG* Raster imagery (scanned and photographic)

Mechanical LG* Legend

Mechanical MD Machine design plan

Mechanical MH Material handling plan

Mechanical QP* Equipment plan

Mechanical SC Section

Mechanical SH* Schedule

Mechanical SP Specialty piping plan

Mechanical XD* Existing/demolition plan

Electrical AL Airfield lighting plan

Electrical AP* Auxiliary power plan

Electrical CP Exterior communication systems plan

Electrical DG Diagram

Electrical DT Detail

Electrical EU Electrical utilities plan

Electrical GP Grounding system plan

Electrical IG* Raster imagery (scanned and photographic)

Electrical LG* Legend

Electrical LP Lighting plan

Electrical PP Power plan

Electrical PS* Panel schedule

Electrical QP* Equipment plan

Electrical SH* Schedule

Electrical SS Special systems plan

Electrical XD* Existing/demolition plan

Telecommunications DG Diagram

Telecommunications DT Detail

Telecommunications IG* Raster imagery (scanned and photographic)

Telecommunications LG* Legend

Telecommunications QP* Equipment plan

Telecommunications SH* Schedule

Telecommunications TP Telephone/data plan

Telecommunications XD* Existing/demolition plan

* = No Model File Table available in Appendix A.

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2.4.4 Sheet File Naming Convention

The sheet file naming convention (Figure 2-5) contains four mandatory fields, and the fifth is optional. All fields must be in the correct sequence.

Following the project code, the next 2 characters are the Discipline Designator with either a hyphen or an alphabetical designator (Table 2-3).

The next character is the Sheet Type Designator (Table 2-4) followed by a 2-character Sheet Sequence Number (01–99). Sheet Sequence Numbers do not need to be sequential. This allows for future insertion of sheets during design. The final field is a 10-character (maximum) user-definable field.

Figure 2-5. Sheet file naming convention.

When multiple sheets are in the same file, the word “SET” may replace either the Sheet Sequence Number (for all sheets under a specific sheet type designator) or the Sheet Type Designator and Sheet Sequence Number (for all sheets under a specific Sheet Type Designator).

Alternately, the first and last sheet in a file may be listed as part of the user-definable field. The sheet filename shall coincide with the sheet identifiers that it contains.

ERDC/ITL SR-24-3 21

Table 2-3. Sheet file discipline designators.

Discipline Designator Description Content

General G- All general All or any portion of subjects in the following Discipline Designators

General GI General information Drawing index, code summary, symbol legend, orientation maps

General GC General contract Phasing, schedules, contractor staging areas, fencing, haul routes, erosion control, temporary and special requirements

General GR General resource Photographs, soil borings

Hazardous materials H- All hazardous materials

All or any portion of subjects in the following Discipline Designators

Hazardous materials HA Asbestos Asbestos abatement, identification, containment

Hazardous materials HC Chemicals Toxic chemicals handling, removal, storage

Hazardous materials HL Lead Lead piping, paint removal

Hazardous materials HP PCB PCB containment and removal

Hazardous materials HR Refrigerants Ozone depleting refrigerants

Survey/mapping V All survey/mapping All or any portion of subjects in the following Discipline Designators

Survey/mapping VA Aerial survey Aerial surveyed points and features

Survey/mapping VB Boundary Boundary survey

Survey/mapping VC Computated points Computated points and features

Survey/mapping VF Field survey Field surveyed points and features

Survey/mapping VH* Hydrographic survey Hydrographic surveyed points and features

Survey/mapping VI Digital survey Digitized points and features

Survey/mapping VN Node points Node points and features

Survey/mapping VS Staked points Staked points and features

Survey/mapping VU Combined utilities

Survey/mapping VL Land Land/property/American Land Title Assoc. (ALTA) survey

Geotechnical B- All geotechnical All or any portion of subjects in the following Discipline Designators

Geotechnical BB* Boring logs Boring logs

Geotechnical BS* Stratigraphy Stratigraphy profiles

Civil CD Civil demolition Structure removal and site clearing

Civil C- All Civil All or any portion of subjects in the following Discipline Designators

Civil CS Civil site Plats, topographic, dimension control

Civil CG Civil grading Excavation, grading, drainage, erosion control, retention ponds

ERDC/ITL SR-24-3 22

Table 2-3 (cont.). Sheet file discipline designators.

Discipline Designator Description Content

Civil CT Civil transportation Waterways, wharves, docks, trams, railways, airfields, people movers

Civil CP Civil paving Roads, driveways, parking lots

Civil CU Civil utilities Water, sanitary sewer, storm sewer, power, communications, natural gas, steam systems

Civil CI Civil improvements Pavers, flagstone, exterior tile, furnishings, retaining walls, water features

Civil CB* Civil beach renourishment

Beach disposal and renourishment

Civil CE* Civil ecosystem restoration

Environmental restoration

Civil CF* Civil flood control Levees, spillways, pump stations

Civil CH* Civil shore protection Erosion protection structures on shoreline

Civil CN* Civil navigation Navigation, harbors, dredging

Civil CO* Civil operation and maintenance

Repair and upgrade to O&M structures

Civil CR* Civil recreation Recreation facilities

Civil CX* Civil security Security-related work

Landscape LD Landscape demolition Protection and removal of existing landscape

Landscape L- All Landscape All or any portion of subjects in the following Discipline Designators

Landscape LS Landscape site All site hardscape and callouts

Landscape LG Landscape grading Proposed contours and spot grades

Landscape LI Landscape irrigation Mainlines, valves, controllers, pumps, etc.

Landscape LL Landscape lighting -

Landscape LP Landscape planting Landscape planting

Landscape LR Landscape relocation Vegetation relocation information

Structural SD Structural demolition Protection and removal

Structural S- All Structural All or any portion of subjects in the following Discipline Designators

Structural SS Structural site -

Structural SB Structural substructure

Foundations, piers, slabs, retaining walls

Structural SF Structural framing Floors and roofs

Structural SC* Structural components

Gates, armor, bulkheads, railings

Structural SR* Structural reinforcement

Concrete reinforcement and anchors

ERDC/ITL SR-24-3 23

Discipline Designator Description Content

Structural ST* Structural superstructure

Walls, decks, abutments, gates, weirs

Architectural AD Architectural demolition

Protection and removal

Architectural A- All Architectural All or any portion of subjects in the following Discipline Designators

Architectural AS Architectural site -

Architectural AE Architectural elements

General architectural

Architectural AI Architectural interiors -

Architectural AG Architectural graphics -

Architectural AF Architectural finishes -

Interiors ID Interior demolition Protection and removal

Interiors I- All Interiors All or any portion of subjects in the following Discipline Designators

Interiors IN Interior design -

Interiors IF Interior furnishings -

Interiors IG Interior graphics Murals and visuals

Fire Protection FD* Fire protection demolition

Protection and removal

Fire Protection F- All Fire protection All or any portion of subjects in the following Discipline Designators

Fire Protection FA Fire protection detection and alarm

Fire Protection FX Fire protection suppression

Fire extinguishing systems and equipment

Plumbing PD Plumbing demolition Protection, termination, removal

Plumbing P- All Plumbing All or any portion of subjects in the following Discipline Designators

Plumbing PS Plumbing site Extensions and connections to Civil Utilities

Plumbing PL Plumbing fixtures Domestic water, sanitary and storm drainage, fixtures

Plumbing PP Plumbing piping Piping, valves, insulation

Plumbing PQ Plumbing equipment Pumps and tanks

Mechanical MD Mechanical demolition

Protection, termination, removal

Mechanical M- All Mechanical All or any portion of subjects in the following Discipline Designators

Mechanical MS Mechanical site Utility tunnels and piping between facilities

Mechanical MH Mechanical HVAC Ductwork, air devices, equipment

ERDC/ITL SR-24-3 24

Discipline Designator Description Content

Mechanical MI Mechanical instrumentation

Instrumentation and controls

Mechanical MP Mechanical piping Chilled and heating water, steam

Mechanical MY* Mechanical hydraulic systems

Pump stations, spillways, slide gates

Mechanical MW* Mechanical distributed energy

Electrical ED Electrical demolition Protection, termination, removal

Electrical E- All Electrical All or any portion of subjects in the following Discipline Designators

Electrical ES Electrical site Exterior electrical systems (power, lighting, auxiliary)

Electrical EI Electrical instrumentation

Controls, relays, instrumentation, measurement devices

Electrical EL Electrical interior lighting

Interior lighting

Electrical EP Electrical interior power

Interior power

Electrical ET Electrical telecommunications

Telephone, network, voice, and data cables

Electrical EY Electrical interior auxiliary systems

Alarms, nurse call, security, CCTV, PA, music, clock, program

Electrical EA* Electrical airfield lighting and navaids

Visual air navigation systems

Electrical EC* Electrical cathodic protection

Cathodic protection systems

Electrical EG* Electrical grounding Grounding, lightning protection devices

Electrical EW* Electrical distributed energy

Telecommunications TD* Telecommunications demolition

Protection, termination, removal

Telecommunications T- All Telecommunications

All or any portion of subjects in the following Discipline Designators

Telecommunications TA Audio visual Cable, music, CCTV systems

Telecommunications TC Clock and program Time generators and bell program systems

Telecommunications TI Intercom Intercom and public address systems

Telecommunications TM Monitoring Monitoring and alarm systems

Telecommunications TN Data networks Network cabling and equipment

Telecommunications TT Telephone Telephone systems, wiring, equipment

Telecommunications TY Security Access controls and alarm systems

ERDC/ITL SR-24-3 25

Discipline Designator Description Content

Telecommunications TS* SCADA Supervisory control and data acquisition (SCADA) systems and equipment

Resource R- All resource All or any portion of subjects in the following Designators

Resource RC Resource civil Surveyor’s information and existing civil drawings

Resource RS Resource structural Existing facility structural drawings

Resource RA Resource architectural

Existing facility architectural drawings

Resource RM Resource mechanical Existing facility mechanical drawings

Resource RE Resource electrical Existing facility electrical drawings

Resource RR Resource real estate Real estate drawings

Resource RG* Resource green LEED drawings

Other disciplines X — —

Operations O — —

* = Not in NCS 6.0

Table 2-4. Sheet type designators.

Sheet Type Designator

General (symbols legend, notes, etc.) 0

Plans (horizontal views and combination plan and profile) 1

Elevations and profiles (vertical views) 2

Sections (sectional views, cross sections, etc.) 3

Large scale views (Scaled up reproductions of plans, elevations, or sections that are not details)

Details 5

Schedules and diagrams 6

User defined 7

User defined 8

3D representations (isometrics, perspectives, photographs) 9

Note: If the sheet sequence number goes above 99 sheets for a particular discipline, the user might want to consider using alphabetical Designators in the Discipline Designator to further subdivide the discipline (Table 2-3).

Note: In the NCS, user-defined “Level 2 Discipline Designators” (two alphabetical characters) in the Discipline Designator are allowed “to differentiate among multiple buildings on a ‘campus’ or among multiple

ERDC/ITL SR-24-3 26

features on a large civil works project.” The A/E/C CAD Standard limits the Discipline Designator field to strictly those listed in Table 2-3 for sheets. The Project Code field (see Section 2.4.1 ) in conjunction with the title block “BLDG ID” field (see “Border Sheets” section in the A/E/C Graphics Standard) preempts the need for this functionality.

Note: Occasionally, more than one Sheet Type (e.g., plan, elevation, detail) will be represented in one sheet file. If this is the case, the dominant Sheet Type determines the Sheet Type Designator.

2.4.4.1 Adding a Sheet

If a sheet needs to be added between two sequential sheets, a Supplemental Drawing Designator may be appended to the end of a sheet file name as part of the user-definable field (Figure 2-6). For example, if two sheets need to be added between sheets ERDC8000A-104 and ERDC8000A-105, then the sheet file names for the inserted sheets would be ERDC8000A104A and

ERDC8000A104B.

Figure 2-6. Supplemental drawing designator.

If time permits, sheet files should be resequenced and named appropriately before advertisement. After advertisement, all sheet additions and deletions shall be documented as an amendment or modification per contract language. See the A/E/C Graphics Standards for more information.

2.4.4.2 Coordinating Sheet Identifiers

The sheet identifier (shown in the sheet identification block, reference bubbles, notes, etc.) shall consist of the discipline designator, sheet type designator, and the sheet sequence number (Figure 2-7).

ERDC/ITL SR-24-3 27

The sequence of the discipline designators in a drawing set shall follow the order as shown in Table 2-3 (except for general notes, abbreviations, and legends that will precede all other sheets in a discipline).

Figure 2-7. Typical border sheet title block with sheet identification block.

ERDC/ITL SR-24-3 28

3 Graphic Concepts

3.1 Presentation Graphics

The first step in establishing an effective CAD standard is the development of a uniform approach to presentation graphics. Presentation graphics typically consist of drawing elements such as lines, arcs, shapes, text, and their attributes (line color, line width, line style). This chapter presents brief overviews of the characteristics of presentation graphics and the philosophy used to standardize them. For more definition, see the A/E/C Graphics Standard.

3.1.1 Line Widths

Commercial CAD systems provide an extensive variety of line widths to substantially improve drawing readability. For the majority of A/E/C drawings, the eight line widths defined in Table 3-1 are considered sufficient and should not be expanded unless an appreciable improvement in drawing clarity or contrast can be realized. Table 3-1 lists information about the various allowed line widths.

Table 3-1. Comparison of line widths.

Line Thickness mm in.

MicroStation Line Weight Typical Use

Fine 0.18 0.007 wt = 0 Patterning and material indications

Thin 0.25 0.010 wt = 1 Dimension lines, leaders, extension lines, break lines, grid lines, schedule grid lines, hidden objects, center lines, setback lines

Medium 0.35 0.014 wt = 2 Forward/back object lines, property lines, terminator marks, schedule grid accent lines

Wide 0.50 0.020 wt = 3 Major object lines, cut lines, section cutting plane lines, property lines, drawing block borders

Extra wide

0.70 0.028 wt = 5 Minor title underlining, footprints, match lines, schedule outlines, sheet borders, object lines requiring special emphasis

XX Wide 1.00 0.040 wt = 7 Major title underlining and separating portions of drawings

XXX Wide 1.40 0.055 wt = 10 Border sheet outlines and cover sheet line work

XXXX

Wide

2.00 0.079 wt = 15 Border sheet outlines and cover sheet line work

ERDC/ITL SR-24-3 29

Note: The NCS does offer an Extra Fine (0.13 mm) line width. However, the legibility on printouts becomes more difficult when the line width goes below the Fine (0.18 mm) line width. The NCS even states “Use of Extra Fine line widths should be avoided if the drawing will be plotted half-size.”

3.1.2 Line Types/Styles

The predominant line types/styles used in this standard are shown in Figure 3-1 and are available as line types/styles for AutoCAD and MicroStation (except for “Continuous”). Additional custom line style files for MicroStation and AutoCAD are available on the Center’s website at https://cadbimcenter.erdc.dren.mil.

Figure 3-1. Predominant line types/styles.

Note: For consistency and interoperability, use of the IGDS default Bentley line styles 1–7 shall be avoided.

3.1.3 Line Color

The primary reason to use color in CAD drawings is to improve the clarity of the drawing on a computer monitor or plot. The variety of colors available in a CAD application depends on the capabilities of the computer monitor, its video card or plotter, and the user’s ability to see them.

Colors within the model file tables are not listed by their AutoCAD or MicroStation color numbers, but instead by their red-green-blue (RGB) values. Using RGB values instead of CAD package color numbers will allow for universal representation of colors no matter which (CAD) software application is being used. Table 3-2 lists the basic colors used predominantly throughout the model files. Additionally, the level/layer https://cadbimcenter.erdc.dren.mil/

ERDC/ITL SR-24-3 30

colors have been defined to reflect industry field marking color standards where applicable.

Table 3-2. Basic colors.

Color RGB Values

Red Green Blue Blue 0 0 255

Gray 128 128 128

Green 0 255 0

Red 255 0 0

Yellow 255 255 0

Magenta 255 0 255

Cyan 0 255 255

White 255 255 255

Note: For AutoCAD, use color “White” or for Bentley use color 0 (zero) for all colors set to 255,255,255 to enable white/black color switching based on background color.

3.1.4 Plotting

Plotted documents are controlled by various files within the CAD application (pen tables, plot drivers, design scripts, feature tables, etc.).

These files set the display of objects (i.e., line thickness, color, etc.) within the plotted document. Agencies should ensure that consistent drawings are produced from a digital file regardless of the type of printer or plotter used.

Each agency may develop plot settings (derived from the A/E/C Standards) needed to convey the design intent (i.e., screening, color plotting, etc.).

Note: For consistency/interoperability, it is recommended that plots first be sent to a common format, such as PDF, before paper plotting.

3.1.5 Screening/Dithering

Screening is the varying of the intensity of grayscale linework. Dithering is the process in which the density and pattern of black and white dots are varied to simulate different shades of gray. Both allow users to distinguish different aspects of a drawing when it is plotted.

ERDC/ITL SR-24-3 31

For example, the existing items to remain on a demolition plan can be assigned with a set screening percentage. When plotted, those items will be displayed at a lighter shade compared to items slated for demolition.

This will allow the viewer to immediately identify the emphasized demolition items on the plotted document.

Table 3-3 lists colors recommended to be used for screening along with a recommended screening percentage. Optionally, when variations in screening are not important, a single screening can be applied to all screened graphics.

Screening can be accomplished with various techniques, but the screen percentages should be the same as Table 3-3. Document any methods used and provide appropriate supporting files.

Table 3-3. Screened colors.

Color No.

Screen Percent

Red Grayscale Ratio

Green Grayscale Ratio

Blue Grayscale Ratio

250 60 102 102 102

251 50 128 128 128

252 40 153 153 153

253 30 179 179 179

254 20 204 204 204

Note: The AutoCAD vs. MicroStation color numbers have been combined to avoid confusion when creating a screened effect in either software. See AutoCAD and MicroStation help documentation for more information on how to perform screening.

3.2 Text

Since projects designed in CAD are planned for use many years into the future and files will be used by many different individuals, use of any nonstandard or…