Trapezoid Concrete Calculator
This trapezoid concrete calculator handles four-sided pours with two parallel edges — flared driveway aprons, tapered walks and wedge slabs. Enter both parallel sides, the distance between them, and the thickness.
Come usare questa calcolatrice
- Inserisci le tue dimensioni — piedi per le lunghezze, pollici per lo spessore.
- Regola le opzioni — percentuale di sfrido, dimensione del sacco e il prezzo locale del calcestruzzo.
- Leggi i risultati — volume, sacchi, peso e costo si aggiornano in tempo reale mentre digiti.
La formula
Trapezoid volume = ½ × (side A + side B) × height × thickness Esempio svolto: An apron 12 ft at the street, 8 ft at the garage, 10 ft deep, 4 in thick: 0.5 × (12+8) × 10 × 0.333 = 33.3 ft³ ≈ 1.23 yd³.
The concrete calculator trapezoid formula averages the two parallel sides — a trapezoid is just a rectangle at the average width. Driveway aprons that flare to the street are the everyday example.
Measure the two parallel edges and the perpendicular distance between them (not a slanted side). Non-parallel side lengths don't enter the formula at all.
Sloped ramps are a different trapezoid — vertical rather than plan-view. For a ramp of constant width whose thickness tapers, use average thickness in the rectangle calculator: (thick end + thin end) ÷ 2.
Domande frequenti
Domande comuni sulla trapezoid concrete calculator.
How do I calculate a trapezoid slab?
Average the two parallel sides, then multiply by the distance between them and the thickness. ½(a+b) × h × t.
Which sides do I measure?
The two parallel edges (A and B) and the perpendicular height between them. The slanted connecting sides are not used.
How do I handle a sloping ramp?
For a ramp of constant width with tapering depth, use the rectangle calculator with the average of the two end thicknesses.
What waste factor for aprons?
5–10%. Flared aprons meet existing pavement, so edges are often ragged — round up.
Calcolatrici correlate
Altri strumenti della famiglia di calcolatrici per calcestruzzo.