Gravel Calculator Triangle

How the Triangle Gravel Calculator Works

1. Compute the Triangle’s Area (Heron’s Formula)

Given the three side lengths a, b, and c of your triangular area:

• Semi‐perimeter (s):
  s = (a + b + c) / 2
• Area:
  $$\sqrt{s\cdot (s-a)\cdot (s-b)\cdot (s-c)}$$

2. Convert Depth to Matching Units

If you enter the gravel depth d in inches, convert it to feet:

dft = din / 12

3. Calculate Gravel Volume

Multiply the plan‑view area by the depth:

Volume = Area × dft (in cubic feet)

4. Convert to Other Volume Units

• Cubic yards: Volumeyd³ = Volumeft³ / 27
• Metric: if using metres, volume is already in m³

5. Estimate Weight Using Density

Multiply volume by gravel density ρ:

Weight = Volume × ρ

• Imperial: ρ in lb/ft³ → weight in lbs, then ÷ 2000 for tons
• Metric: ρ in kg/m³ → weight in kg, then ÷ 1000 for tonnes

Default density: 1,600 kg/m³ (≈100 lb/ft³), but you can override if your material differs.

Summary of Steps

1. Input sides a, b, c, depth d, and density ρ.
2. Compute s = (a + b + c) / 2 and area via Heron’s formula above.
3. Convert d to feet if needed and calculate Volume = Area × dft.
4. Convert volume to cubic yards or cubic metres as desired.
5. Compute Weight = Volume × ρ for lbs/tons or kg/tonnes.

Common Applications of a Triangle Gravel Calculator

• Patio Corners: Perfect for triangular patios or seating nooks where you need precise gravel quantities.
• Garden Borders: Estimating gravel for triangular planting beds or edging along walkways.
• Driveway Aprons: Calculating fill for triangular off‑shoots at driveway entrances.
• Deck Foundations: Gravel base under triangular deck extensions or supports.
• Play Areas: Triangular sandbox or play pad surrounds requiring uniform gravel depth.

Best Gravel for Triangle-Shaped Areas

Choosing the right gravel improves drainage, stability, and appearance:

• #57 Crushed Stone: Angular, locks together, ideal for load‑bearing corners.
• Pea Gravel: Smooth, decorative—best for low‑traffic triangular patios.
• Decomposed Granite: Fine, compacts well—great for formal triangular garden paths.
• Crushed Limestone: Durable, moisture‑resistant—recommended under triangular deck footings.

Recommended Gravel Depths for Triangles

Maintaining Your Gravel Triangle Area

• Rake Annually: Even out any low spots and redistribute gravel.
• Add 1–2″ Top‑Ups: Replace settled gravel every couple of years.
• Edge Restraints: Keep your triangle shape crisp with steel or stone edging.
• Weed Control: Install or refresh landscape fabric underneath.