How to use an Architect's Scale Ruler

Scale rulers are used by architects and engineers to calculate dimension in a blue print or building plan without the use of time-consuming and complicated math equations.

Difficulty: Moderately Easy

Instructions

Things You'll Need:

• blue prints or building plans, scale ruler

Using a Scale Ruler

1. Determine the scale of your plans. It will be labeled on the plans and should be found in the bottom corner.

2. Turn the ruler to the corresponding scale factor. For instance, if the plans read ¼ inch equals one foot, you will use the ¼ inch scale on the ruler.

3. Measure the desired line starting from zero on the correct scale. In this case, you would need to use the ¼ inch scale.

4. The measurement you calculate equals how many feet the line actually is at full scale dimensions.

5. Try it out several times until you get the hang of it. This will increase your understanding of the scale ruler so you can use it with ease.

Tips & Warnings

• Be sure you are using the correct scale on the ruler. If you use the wrong scale on the ruler, all your measurements will be incorrect.

[cadstudent]

on 10/3/2009 If it lists the scale as 1/8 = 1'0" that is the scale you should be using. You should not be doubling it and using the 1/16" scale. The 1/8 scale goes up to 92 feet. The 1/16 scale only goes to 12" (1 foot). 1/16 scale is your regular ruler.

[rustycent]

on 2/12/2009 I am trying to use a scale rule of 1:20

|....|....|....|....|....| etc
0 50
The markings are only 25 not 50 as marked on the rule, why and what do's it mean.
Rustycent

[Zorra]

on 1/7/2009 Hello! I could probably provide better assistance if you tell me your original paper size and scale factor. 1/16th divided into one inch is 1/16th. If your paper size is not truly half of your original drawing size, then your scale factor will be distorted. For instance, a 22 x 34 drawing will be 11 x 17 at half size. This is a valid paper size. On the other hand, a 24 x 36 drawing will be 12 x 18 at half size, and this is not a valid paper size.

Hope this helps. Good luck to you.

[FallGuy]

on 1/5/2009 Let’s say my scale is 1/8 and the drawing is half size.
Therefore my scale is 1/16.
When using 1/8 scale I take the measure amount and multiple it by two
This is correct.
However when I use a 1/16 scale the answer is incorrect and that is because it is not 1/16 scale. It is one inch divided into 1/16th. Why is that?
What is going on here?