Decomposed Granite Cost Calculator

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Decomposed Granite Cost Calculator
Rectangular Area
Estimated Results:
Enter values and click Calculate to see results.
function calculateDG(){var l=parseFloat(document.getElementById('length').value);var w=parseFloat(document.getElementById('width').value);var d=parseFloat(document.getElementById('depth').value);var p=parseFloat(document.getElementById('price').value);var del=parseFloat(document.getElementById('delivery').value);if(isNaN(l)||isNaN(w)||isNaN(d)||isNaN(p)){alert('Please enter valid numeric values.');return;}if(isNaN(del)){del=0;}var cubicFeet=l*w*(d/12);var cubicYards=cubicFeet/27;var tonsNeeded=cubicYards*1.4;var materialCost=tonsNeeded*p;var totalCost=materialCost+del;var showSteps=document.getElementById('steps').checked;var resultHTML='
Total Cost: $'+totalCost.toFixed(2)+'
';resultHTML+='
Material Needed: '+tonsNeeded.toFixed(2)+' Tons ('+cubicYards.toFixed(2)+' cubic yards)
';if(showSteps){resultHTML+='
';resultHTML+='Steps:
';resultHTML+='1. Area: '+l+' ft x '+w+' ft = '+(l*w)+' sq ft
';resultHTML+='2. Volume: '+(l*w)+' sq ft x '+(d/12).toFixed(4)+' ft (depth) = '+cubicFeet.toFixed(2)+' cu ft
';resultHTML+='3. Convert to Yards: '+cubicFeet.toFixed(2)+' / 27 = '+cubicYards.toFixed(2)+' cu yd
';resultHTML+='4. Convert to Tons: '+cubicYards.toFixed(2)+' x 1.4 (density) = '+tonsNeeded.toFixed(2)+' tons
';resultHTML+='5. Subtotal: '+tonsNeeded.toFixed(2)+' tons x $'+p+' = $'+materialCost.toFixed(2)+'
';resultHTML+='6. Grand Total: $'+materialCost.toFixed(2)+' + $'+del+' (delivery) = $'+totalCost.toFixed(2);resultHTML+='
';}document.getElementById('answer').innerHTML=resultHTML;}

Using the Decomposed Granite Cost Calculator

Whether you are planning a new garden path, a xeriscape driveway, or a rustic patio, the decomposed granite cost calculator is an essential tool for budgeting your landscaping project. Decomposed granite (DG) is a popular material because of its natural look, permeability, and relative affordability, but estimating the exact tonnage and price can be tricky due to material density variations.

This calculator helps you convert surface area dimensions and desired depth into the total tons required, providing a final cost estimate based on local pricing and delivery fees.

Length & Width (Feet)
The dimensions of the rectangular area you plan to cover. For irregular shapes, use the average length and width.
Depth (Inches)
Standard depth for walkways is 2-4 inches. Driveways usually require 4-6 inches for stability.
Price per Ton
The cost charged by your local quarry or supplier. DG prices typically range from $40 to $80 per ton depending on the color and stabilization.
Delivery Fee
Flat rate charged by the supplier to drop the material at your site. This is often a significant portion of the total cost.

How It Works: The DG Cost Formula

To calculate the cost of decomposed granite, we first determine the volume and then convert that volume into weight (tonnage), as most suppliers sell by weight. The formula used by our decomposed granite cost calculator is:

Total Cost = (((Length × Width × (Depth / 12)) / 27) × 1.4 × Price per Ton) + Delivery Fee

  • Volume in Cubic Feet: Length × Width × (Depth in inches / 12).
  • Cubic Yards: Volume in cubic feet divided by 27 (the number of cubic feet in a yard).
  • Tonnage Factor: We use a standard density of 1.4 tons per cubic yard for compacted DG.
  • Total Tons: Cubic Yards × 1.4.

Calculation Example

Scenario: You want to install a DG patio that is 20 feet long and 15 feet wide. You want the material to be 3 inches deep for durability. The local supplier quotes $60 per ton with a $100 delivery fee.

Step-by-step solution:

  1. Square Footage: 20 ft × 15 ft = 300 sq ft
  2. Cubic Feet: 300 sq ft × (3 / 12 ft) = 75 cu ft
  3. Cubic Yards: 75 / 27 = 2.78 cu yd
  4. Tonnage: 2.78 cu yd × 1.4 = 3.89 Tons
  5. Material Cost: 3.89 tons × $60 = $233.40
  6. Grand Total: $233.40 + $100 (delivery) = $333.40

Factors Affecting Decomposed Granite Pricing

While the decomposed granite cost calculator provides a solid estimate, several variables can influence the final price you pay at the register:

Stabilized vs. Natural DG

Natural DG is simply the weathered rock. Stabilized DG contains a binder (usually organic) that helps the particles stick together, reducing dust and erosion. Stabilized DG can cost double the price of natural DG but lasts significantly longer in high-traffic areas.

Color Selection

Common tan or gray DG is usually the cheapest. Rare colors like "California Gold," "Rose," or "Blue-Green" may require shipping from distant quarries, which increases the price per ton significantly.

Compaction Loss

When you compact DG with a plate compactor, the material "shrinks" in volume. Our calculator uses a 1.4 density factor to account for this, but if you are doing a very deep installation, you might want to order 5-10% extra to ensure you reach your desired finish grade.

Common Questions

How much does a cubic yard of DG weigh?

On average, one cubic yard of decomposed granite weighs between 2,400 and 2,800 pounds, which is approximately 1.2 to 1.4 tons. Damp or compacted DG will be on the heavier end of that spectrum.

Is it cheaper to buy DG by the bag or in bulk?

Bulk is almost always cheaper if you need more than half a ton. Buying 40lb bags at a big-box store can cost $5-$10 per bag, which equates to over $250 per ton. Buying in bulk from a landscape supply yard usually costs $40-$80 per ton.

Does DG need a weed barrier?

While not strictly necessary for the structural integrity of the DG, a heavy-duty landscape fabric is recommended underneath to prevent the granite from mixing with the native soil and to suppress weed growth.

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