Layout Squaring (3-4-5)
Diagonal to pull and out-of-square diagnosis for a rectangular layout.
Example
You enter
- Mode find-diagonal
- Side a 3
- Side b 4
You get
- Ideal diagonal 5
Checked against published worked examples from: Pythagorean 3-4-5 method (public).
Details, formula, and sources
Formula or tableDiagonal = sqrt(a^2 + b^2) (Pythagoras / the 3-4-5 rule). For a rectangle the two diagonals are equal when square, so out-of-square = |d1 - d2| and the longer diagonal's corner is the one to draw in.
Source and editionThe Pythagorean 3-4-5 right-angle layout method (public) and the standard foundation- and deck-squaring technique.
Free accessPublic first-principles geometry; no paywalled source.
What governsEstimate. AHJ and licensed professional govern.
API field namesmode, side_a, side_b, ideal_diagonal
- Rectangular assumption the check-square mode assumes a rectangle (equal diagonals when square)method