Building and Construction

Architect Scale vs. Engineer Scale

06 February 2018

Source: CIASource: CIA

Architects and civil engineers are involved in planning and designing structures. An architect’s primary objective is to design and develop structures with an emphasis on spatial functionality and aesthetics.

Civil engineers, on the other hand, evaluate the structural integrity and identify suitable materials and modifications that are required to support the architecture. While the two professions are closely related, their job functions are unique and the tools they use to evaluate their design proposal are unique as well.

Architectural and civil drafters produce technical drawings and plans, often referred to as building plans or blueprints. Computer-aided design and drafting (CADD) software systems allow them to complete the design and produce hard copies of 2D or 3D drawings. The physical blueprint is produced to scale and each feature is proportionately the same as the artifact it represents. Due to the nature of the spatial field included in the design proposal, each profession has their own scale, which is referred to as an architect scale or an engineer scale.

What is an Architect Scale?

Scales are prism-shaped tools that resemble a ruler. Architect scales use standard proportional ratios with 0.25 in. (1/48 size) or 0.125 in. (1/96 size) being most common. These ratios are most appropriate for representing interior and exterior dimensions of rooms, walls, doors, windows and fire protection system.

Architect scales are enumerated incrementally, both from left to right and from right to left, typically with a different dimensional relationship in each direction. Graduations on an architect scale are enumerated with whole numbers that represent the true size of the artifact in the drawing in feet. A quarter-inch dimension on a 1/48 architect scale represents one foot, or 48 quarter inches. The inch graduation for this scale would be enumerated by the whole number 4.

The zero (“0”) point on an architect scale is not on the extreme end of the tool. Fractions of the dimensional ratio are followed by the zero mark, which is then followed by whole numbers at each principal graduation, which can be etched, scribed, engraved or printed on the tool. The dimensional ratio of the scale is typically located immediately adjacent to the first graduation while color-coded furrows help delineate different scales on each side of the prism-shaped tool.

What is an Engineering Scale?

Engineer scales are also prism-shaped tools. The scale is divided into decimalized fractions of an inch. The six faces of the prism have the following dimensional ratios 1:10, 1:20, 1:30, 1:40, 1:50 and 1:60 unless otherwise stated.

The first graduation on an engineer scale is the zero mark. Values or whole numbers on the scale must be multiplied by 10 in order to obtain the true size of the artifact in feet. The dimensional ratio is also listed adjacent to the first graduation and is dually identified by color-coded furrows. The tool is typically only enumerated incrementally from left to right.

In civil engineering applications, each scale serves a unique application. The 1:10 (1 in. =10 ft.) scale is used exclusively for detail drawings. 1:20 and 1:40 scales are used for working plans and 1:60 is used to draft large areas of a project.

Taking Measurements

It is paramount that the proportional ratio of the blueprint matches the scale ratio when taking measurements. The instruments are used exclusively for taking linear measurements and should not be used for drafting or drawing.

To take a measurement, align the zero mark with one end of the object. The objects endpoint will represent the object’s length when built-in feet. Remember to multiply this figure by ten when using an engineering scale.


Using Engineer and Architect Scales

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Discussion – 2 comments

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Re: Architect Scale vs. Engineer Scale
2018-Feb-06 9:18 AM

This brings back memories. My old engineer scale is collecting dust someplace in a box in my basement right now. It's kind of gone the way of the slide rule since CAD arrived on the scene. Does anybody still use their scales or draw by hand?

Re: Architect Scale vs. Engineer Scale
In reply to #1
2018-Feb-06 5:27 PM

Well, I do still draw by hand, on occasion, but I am an unregistered luddite, by nature...

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