Mastering Math: How to Do Pythagorean Theorem Without a Calculator

Wait….  What?  8th grade geometry on a home building blog?  

This isn’t what you came here for is it????  

Actually, Pythagorean’s Theorem is one of the most of important pieces of mathematics in construction!  It is hugely important that walls are built square, plumb, and level.  The way to do this is to use Pythagorean’’s Theorem:

Now you may be thinking, do construction workers really work out square roots and algebra to figure out how to build homes in the heat, cold, rain and speed of a job site - the answer is YES!  ….ok, the answer is Kind Of!  A quick and dirty trick to figure out if what you are building is square (a 90 degree angle) is to simply use the “3-4-5 Rule”.  If you measure 3’ from one corner, 4’ from the other, you simple have to adjust the angle until the space between those two marks (the hypotenuse) is 5’.  This will guarantee you have created a right angle!  

Feel free to use this rule anytime you are working on something around your home - Planter Beds, Fences, Pavers, or even sand boxes are all projects that can benefit from this knowledge!  Check out the video below of us teaching this important skill to the next generation!