How to lay out a 90 deg. Angle with just a measuring tape

Trying to lay out a garden plot, a small shed, a patio or other remodeling project and you need to make a 90 degree angle? You can do it with a measuring tape and a few markers.

Difficulty: Easy

Instructions

Things You'll Need:

• A project that needs a right angle laid out
• A measuring tape
• Stakes, pins, or other markers to mark where you measure to

1. 
    
   Starting point and base line

   Start with a straight line that is one side of whatever you are making. Call the end of the line where you need the 90 degree angle A.

2. 
    
   A to B

   From point A measure 3 feet along the line to point B and mark this point.

3. 
    
   4 foot arc

   From point A measure in the direction you need to go with your 90 degree angle for a distance of 4 feet. Mark an arc on a 4 foot radius from point A.

4. 
    
   5 foot arc

   From point B measure toward the arc you just made in step 3 a distance of 5 feet. Mark another arc on a 5 foot radius from point B and intersecting with the first arc you made in step 3.

5. 
    
   Finished!

   Where these 2 arcs intersect we will call it point C. Now draw a line from point A to point C and it will be an exact 90 degree angle.

Tips & Warnings

• The line AC may be extended to whatever length you need it to be.
• You may use any unit of measure you wish, feet, inches, yards, etc. as long as you maintain the 3-4-5 relationship in your measurements.
• You may also multiply the measurements by the same amount in order to get a line that is close to the length you want. Example: 6-8-10 12-16-20 or whatever fits your project, again, as long as you maintain the 3-4-5 relationship in your measurements.
• You may get a swelled head when you tell your friends how you did this.