What on earth should be done with those endless CAD drawings that never seem to end?

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As a designer, when using the Haochen CAD software to create drawings, in addition to the actual design work, modifying CAD drawings is also one of the important and common tasks. But why do some people make changes quickly, while others become so disturbed by the process of editing images that they lose their sanity? In fact, apart from regular design issues, it’s very likely that there are problems with the annotations on the CAD drawings! For example, errors in dimension marking, errors in scale indication, mistakes in design approach, issues with legend markings, and so on. These seemingly minor issues need to be taken into account when drawing; below, I’ll share some common techniques and tables with you! I. Common and usable scales in building drawings As we all know, buildings are large and complex in structure; therefore, various scales are needed when drawing them. The entire building as well as its detailed components are usually drawn on a reduced scale. So, what is the typical scale used? Look at the figure below. II. Width of lines: To distinguish between the different elements represented by the lines in architectural drawings and to create a clear hierarchy, it is necessary to use lines with various line styles and thicknesses. Generally, the main lines in the diagram are drawn with thicker lines, while the secondary lines are drawn with thinner lines. For the specific width, see the figure below. III. Positioning axes and their numbering: The positioning axes in building construction drawings are used for construction positioning and setting out. Axes should be drawn for major load-bearing elements such as load-bearing walls and columns. For non-load-bearing partition walls, secondary load-bearing elements, etc., a dividing axis is generally used. The alignment axis is shown on the diagram with thin dashed lines and numbered. Vertical numbering uses uppercase Latin letters, arranged in order from bottom to top. The additional sub-axis between the two main axes can be numbered using fractions, where the denominator represents the number of the main axis and the numerator represents the number of the additional axis, written in sequential Arabic numerals. The three uppercase Latin letters I, O, and Z shall not be assigned axis numbers to avoid confusion with digits. IV. Dimensions and elevations: Except for elevations and the overall building layout, which are expressed in \"m (meters)\", all other dimensions are expressed in \"mm (millimeters)\". The unit for elevation values is “m (metres)”. In construction drawings, the values should be expressed to three decimal places, while in site plans they should be expressed to two decimal places. In building construction projects, the zero level is indicated as ±0.000; a “-” sign must be placed in front of negative elevation values, while no “+” sign is needed in front of positive elevation values. In site plans, the notation for elevation values follows the same rules as mentioned above. V. There are two types of elevations: absolute elevation and relative elevation. Absolute elevation: In China, the average sea level in the Yellow Sea near Qingdao is set as the zero point for absolute elevation, with all other elevations being referenced against this value. Relative elevation: Apart from the general layout plan, relative elevation is generally used. Typically, the elevation of the main floor surface is set as the zero point for relative elevation, with all other elevations being measured relative to this value. 6. Compass and wind direction frequency rose diagram: A compass should always be included in the building’s general layout plan; refer to the example of a building’s general layout plan for this. Wind direction frequency rose diagram: On the building’s general layout plan, it is usual to include a wind direction frequency rose diagram based on the local conditions. Wind direction frequency rose diagrams for major cities across the country can be found in the “Building Design Data Book”. In cities where such diagrams are not available, a separate compass is drawn on the general layout plan. These are some of the common CAD drawing standards compiled by the editor; by memorizing these seemingly simple rules, one will no longer have to worry about making changes to drawings in the future! Want to get more related CAD tutorials? Be sure to follow me then!~