Q-CAD’s staff includes CAD operators, quality control managers, architects and engineers. Each staff member is a skilled user of AutoCAD, Revit and MicroStation and works on drawings within their area of technical expertise. Our staff handles all CAD drafting and quality control. We do not outsource to other companies.
We develop a “customer profile” or history for each project. When a future project is submitted, we review the previous history and use profile data that often includes fonts, title blocks, layering, and templates.
CAD layering standards are essential to share graphic information data throughout the architecture, engineering, and construction industries. CAD layering and guidelines help users manage graphic information in their CAD files.
There are many different layering standards and guidelines available for CAD files. Most CAD users rely on the CAD layering standards developed by the American Institute of Architects (AIA). Q-CAD uses the AIA layering standards as the default layering setup. Several other layering standards include the AEC 6.1, Tri-Services, and our Lite layering standards. CAD layers are divided into major groups and then subdivided into minor groups. Each layer is labeled with a simple abbreviation that remains consistent throughout the project.
Major AIA CAD layer groups include:
A Architectural
C Civil
E Electrical
F Fire Protection
G General
H Hazardous Materials
I Interiors
L Landscaping
M Mechanical
P Plumbing
Q Equipment
R Resource
S Structural
T Telecommunications
X Other Disciplines
Z Contractor Shop Drawing
See the complete AIA Layering Guidelines for more information.
The colors for each layer will be consistent and all objects will be drawn in color BYLAYER. This means that all objects assigned to a specific layer will be the same color. Occasionally, the need to create a new layer can arise in cases when custom defined layers or AIA layer standards are not available.
There are other tools that help organize CAD entities. These include symbol libraries, blocks and attributes. These tools allow you to export CAD data to reports or Excel spreadsheets. They also enable software applications to count object symbols, such as doors or windows; or count attributes, such as room numbers or areas for use by space management applications.
What happens when there are ambiguities, such as unclear objects or missing dimensions, on a plan or drawing? For these situations “rules of thumb” are designed to resolve conflicts and enable uniformity.
When original drawings do not have dimensions (or fewer than 20% dimensions on the sheet) our drafting procedure changes somewhat. The CAD operator must manually scale each of the entities on the drawing such as walls, doors, windows, etc. There are often 1 or 2 check points on the drawing that we can use to verify the manually scaled dimensions. These check points can be a scale bar, or an overall building dimension, or a commercial interior door width of 36″ typical. The overall accuracy of the converted CAD file is very high and is reliably within 1%.
Older as-built original drawings may contain unclear dimensions or text that are difficult to read. For these situations, the CAD operator will insert a “red box” on the README layer in the CAD file. The red box indicates the unclear data. You can quickly zoom into the red box area and make necessary modifications.
Occasionally a dimension listed on the original drawing will conflict with the dimension scaled by the CAD operator. In this situation, the dimension shown on your original document is the default. The dimension scaled by the CAD operator shown on the “README” layer. Each dimensional conflict is shown on the README layer should to be reviewed by the customer.
Organizations use their drawings for a variety of purposes ranging from interior renovations to space management. In order to do so, they must first create a set of internal guidelines so that each document remains consistent with the others. This ensures seamless communication. It allows anyone in the organization (or even third-party contractors) to read CAD documents no matter where they are or what software application they’re using. Maintaining consistent standards also allows for the automatic searching and indexing of large numbers of files.
Over the years, Q-CAD has used many different types of CAD conversion procedures and guidelines. Based on our experience, we recommend six standards. You can choose one or all six as inspiration for developing your own in-house standards.
Each sheet should maintain consistent title blocks, logos, and sheet borders. Each sheet size (A, B, C, D, E, F) should have its own title block template.
Ideally, you should draw all document entities, dimensions, symbols, notes, etc. in Model Space.
Consistency often requires a set of present variables.
You should be able to easily identify a specific drawing or building. That requires good file naming conventions. Ideally, the saved file name will contain a combination of the sheet number and the building name or number. It’s also important to add each document to an electronic index immediately after conversion. That allows for easy access and cross-referencing. A good filename convention may look something like this:
Where: E=Drawing Type (such as E=Electrical)
JH=Building number/name (such as Johnson Hall)
0101=Drawing sequence number (sheet number)
01=Revision number or letter
Text should also be standardized between documents, as well as dimensions and linetype styles. Fonts such as ROMANS and ROMAND are standard. It’s also important to define the text height. The text width, on the other hand, should remain flexible. That’s because the width may change depending on the specific content of each sheet, particularly if a sheet is crowded with information. A text style may look something like this:
Example: 08ROMANS15
Where:
08=width factor=0.8=width of letter
ROMANS=font
15=oblique angle (omitted when set to 0)
Many documents contain repetitive entities (e.g., windows, doors, toilets). Blocks are used to represent such objects. It’s important that the blocks remain consistent throughout documents and projects, if necessary. If you use an “X” to define a window in one drawing, then every drawing should mark windows with an “X.” Every employee, contractor, and consultant should also know how to interpret the symbols.
In order to ensure consistency and make interpretation easier, Q-CAD recommends creating a block legend that defines each and every block used. The operator should create the blocks with Layer 0 activated. They should then insert the block into the correct layer in the drawing. After inserting the block, the operator should then re-scale it to match the dimensions of the current drawing. Finally, it’s important to list all blocks in the drawing index and remove any unreferenced blocks from the drawing.
Polygon layers make it easy to calculate the square footage of a space. By drawing a closed polygon over the top of each room and then over the entire building, it’s possible to export precise data such as perimeter, room area, or location of an object. This data can be imported into other software applications.
Q-CAD recommends one of three primary polygon layer standards:
1) BOMA – Building Owners and Managers Association International Standards
2) Institutional – Higher Education, K-12 Schools Standards
3) IFMA – International Facility Managers Association Standards