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Square Footage of a Triangle

Area of a triangular space from its base and height — the shape a gable end or a corner of a room makes.

With base 12 ft, height 8 ft, number of identical areas 1, waste factor 10 percent, square footage comes to 52.8 sq ft — area to order. It is reached in 9 steps, the last of which is subtotal * (1 + waste / 100), and each one is printed on the page with its numbers filled in. The formula is the one published by ANSI Z765 residential square footage measurement standard, not an approximation fitted to it.

Formula and sources checked · How we check

baseheight
What to measure
Area to order
52.8 sq ft
4.9 square metres
The three sides close into a triangle
heron > 0 ? 1 : 01
Area of the openings
openings * opening_w * opening_h30 sq ft
Area per shape
48 sq ft
Total area
area * rooms48 sq ft
Area to order
subtotal * (1 + waste / 100)52.8 sq ft
Same area in square meters
total / 10.76394.905 sq m
Same area in square yards
total / 95.867 sq yd
Same area in acres
total / 435600.001 acres
Material at that price
total * price$0

The formula

  1. The three sides close into a triangleheron > 0 ? 1 : 0
  2. Area of the openingsopenings * opening_w * opening_h
  3. Area per shapeshape_rect * (length * width) + shape_wall * max(0, length * width - openings_area) + shape_border * ((length + 2 * border_width) * (width + 2 * border_width) - length * width) + shape_trapezoid * ((top_width + bottom_width) / 2 * trap_height) + shape_circle * (pi * pow(diameter / 2, 2)) + shape_annulus * (pi * (pow(diameter / 2, 2) - pow(min(inner_diameter, diameter) / 2, 2))) + shape_triangle * (base * tri_height / 2) + shape_triangle_sides * sqrt(heron)
  4. Total areaarea * rooms
  5. Area to ordersubtotal * (1 + waste / 100)
  6. Same area in square meterstotal / 10.7639
  7. Same area in square yardstotal / 9
  8. Same area in acrestotal / 43560
  9. Material at that pricetotal * price

Formula from ANSI Z765 residential square footage measurement standard, NIST Office of Weights and Measures.

The same calculator, other cases

  • Square Footage of a CircleArea of a circular room, patio or pad from its diameter, with the radius step shown rather than folded into one formula.

Undecided? The Square Footage Calculator carries every case behind one control.

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