How to Read Drafting Scales

Drafting scales are tools used to measure lines in a blueprint and translate that measurement to real life. The blueprint was drawn so that you, the builder, could understand the exact size of every wall, floor and beam in the home you are building. The measurements of each item is marked on the print. But, by the time a print makes it to the site these measurements may no longer be readable. A drafting scale will help you to construct the architect's vision for your client.

Things You'll Need

• Blueprints
• Drafting scale

Instructions

1. Lay out the prints on a flat, dry surface. Locate the "scale" marked on the bottom of the drawing.

2. Flip the drafting scale until you locate the proper side. The scale is marked on the right side with markings such as 1/4, 1/2, or 1. The markings on the 1/4 side are in 1/4 inch increments. Place the scale against the line you are measuring.

3. Measure the line on your prints with the scale. Place the 0 of the scale at one end of the line. Locate the other end of the line to the left of the 0. Read the measurement at the end of the line. A 20 on the scale translates to 20 feet on your project, but, it is only 5 inches from the 0 mark on the scale. 1/4 inch = 1 foot.

References

• Triton College: Architectural Drafting Fundamentals