Architectural plans are drawn to all different scales, ranging from the simple (1 inch = 1 foot) to the complex (3/16 inch = 1 foot). Plans are often drawn at 3/4, 3/16, 1/8, and other scales (in each case the dimension in inches here corresponds to one foot).
When you’re faced with figuring out how to convert a two-inch line drawn at a 1/4-inch scale on one drawing to another plan that uses a scale of 1/16 of an inch, the math can quickly become confusing. Fortunately, an essential tool of architects makes the process of decoding the scale of architectural and engineering drawings simple—an architect’s scale ruler (also known as an architectural scale ruler).
A triangular architect scale has a total of six edges, often with two different scales—say both 1 inch to 1 foot and a ½-inch to 1 foot—represented on the same edge. Some sets with multiple rules can include up to 16 scales. These are typically 12 inches long and you can find a remarkable variety to choose from: plastic scales, others of solid aluminum, and ones with color-coded grooves.
If you don’t own one already, it’s an essential tool of the trade for architects, engineers, and builders that you will want to buy now. You can also download a simple printable version from Archtoolbox.
In his Introduction to Reading Blueprints class, professional builder Jordan Smith explains:
“We have a lot of different scales represented in this single ruler. This makes it quick and easy to draw different prints at different scales, as well as interpret different prints at different scales.”
Understanding scales is only one of the many skills you need to read a property’s blueprints. Learn everything you need to know about reading blueprints in MT Copeland’s online class, taught by professional builder and craftsman Jordan Smith.
MT Copeland offers video-based online classes that give you a foundation in construction fundamentals with real-world applications. Classes include professionally produced videos taught by practicing craftspeople, and supplementary downloads like quizzes, blueprints, and other materials to help you master the skills.
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