1. Interior Design II: Objective 5.02
How to Interpret Blueprints: Reading an Architect’s Scale & Understanding the Alphabet of Lines
Interior Design II: Objective 5.02

2. What is an Architect’s scale?
A triangular shaped instrument used for making or measuring scaled drawings such as blueprints or floor plans.

3. What is an Architect’s scale?
The scale can be read from left to right and right to left.
1/8” scale would be read from left to right and the ¼” scale would be read from right to left.

5. Look at the 1/8” scale and read from left to right
Look at the 1/8” scale and read from left to right. The upper numbers represent feet.

6. Look at the 1/4” scale and read from right to left
Look at the 1/4” scale and read from right to left. The lower numbers represent feet.
At 1/4” scale, read from right to left following the lower numbers

7. What does “drawn to scale” mean?
On a scaled drawing, a small measurement is used to represent a large measurement.
For example, one-fourth inch (¼”) on the plan may represent one foot (1’) in the real world.

8. What does “drawn to scale” mean?
Floor plans for residential structures are usually drawn at ¼” = 1’.
Commercial buildings may be drawn at 1/8” = 1’ if they are too large to fit on the desired sheet size at ¼” = 1’.

9. Step 1 Determine the drawing scale.

10. Step 1 Determine the drawing scale.

11. Step 1 Determine the drawing scale.

12. Step 2 Find the matching number on the architect’s scale.

13. UNT in partnership with TEA. Copyright ©. All rights reserved.
Step 3 Place the scale on the print. Place the mark above the zero at the beginning of the line to be measured.
UNT in partnership with TEA. Copyright ©. All rights reserved.

14. Step 4 Use the scale to draw
To draw your own prints, determine the length of the object to be drawn, then scale it down accordingly using the architect’s scale.
For example, using the 1/4”= 1’ example, a wall 20 feet in length would become 20/4 or 5 inches on the blueprint.

15. Example: The Length of a Work Table
Find the “0” point on the ¼ scale …
Align it with the left corner of the table top

16. Example: The Length of a Work Table
Plan View
Looking from Right to Left along the scale, note that the table is “6” units or 6 feet long.

17. Example: Now measuring the height of the table
The table is somewhere between 2 ½ and 3 feet high …Can we be more precise?

18. Example: Worktable Height
Slide the scale down so that the nearest whole foot measure (2’) is aligned with the bottom of the table.

19. Example: Worktable Height
Then read the area “above” the “0” … a distance of about 9” … so the table would be 2’ plus 9” high, or 33” 9” 2’

20. Now it is your turn!