Grab Lorry Sizing Calculator: Estimate Loads and Costs Accurately
When you need to remove waste, soil, or rubble from a site, grab lorries are one of the most efficient options. They can reach over fences and walls, load directly into the vehicle, and haul away material without the need for wheelbarrows or skips. But how many loads will you need? And what will it cost? Our Grab Lorry Sizing Calculator is a free online tool that helps you estimate waste volume, the number of lorry loads required, and the total haulage cost, taking into account waste type, density, weight limits, and site access.
In this guide, we’ll show you how to use the calculator, explain the calculations, provide real-world examples, and answer common questions. We’ll also share tips to keep your muck away project on budget.
Grab Lorry Sizing
Construction CalculatorGrab lorry sizing: waste volume, load capacity, number of loads and cost.
What is the Grab Lorry Sizing Calculator?
The Grab Lorry Sizing Calculator is a free online tool that calculates the number of grab lorry loads needed to remove waste from your site, based on the volume of waste, its density, the lorry size, and any weight restrictions. It also estimates the total cost based on a per-load price. The calculator is part of a suite of earthworks and hauling calculators available on our website. For related calculations, you can use our Muck Away Cost Calculator, Skip Hire Sizing Calculator, and Tipper Truck Hire Calculator. If you’re also excavating, the Spoil Removal / Hauling Calculator provides detailed truck logistics.
How to Use the Grab Lorry Sizing Calculator
Using the calculator is straightforward. Here’s a breakdown of each field:
1. Waste
- Waste type: Select the type of waste: General waste, Garden waste, Soil / subsoil, Rubble / hardcore, Mixed C&D, or Green waste. This is informational—it reminds you to enter the correct density for your waste in the Weight section.
2. Volume
- Volume input: Choose whether to estimate volume from area or enter it directly. Select “Estimate from area” if you know the area and average depth. Select “Direct volume” if you already know the volume in cubic meters.
- Area cleared: Enter the area to be cleared in square meters or square feet. Used only when “Estimate from area” is selected.
- Average depth: Enter the average depth of waste in meters or inches. Used only when “Estimate from area” is selected.
- Direct volume (in place): Enter the volume of waste in cubic meters or cubic yards. Used only when “Direct volume” is selected.
- Bulking factor: Enter the factor that converts in-place volume to loose volume. Loose waste bulks 1.15–1.50 depending on material. The default is 1.30.
3. Lorry
- Grab lorry size: Select the lorry size: 6 yd³ (mini grab), 8 yd³, 12 yd³, 16 yd³ (standard), 20 yd³, 24 yd³, or Custom. The physically selected lorry size—tight access limits to 8 yd³.
- Custom lorry volume: Enter the custom lorry volume in cubic yards or cubic meters. Used only when lorry size is “Custom”.
4. Weight
- Weight limit enforced: Select Yes or No. If Yes, heavy waste is limited by the lorry’s payload.
- Lorry payload: Enter the legal payload per load in tonnes. Usually 16 t for a standard grab lorry.
- Waste density (in place): Enter the density of the waste in kg/m³. Typical values: soil ~1700, rubble ~1800, garden ~500, general ~200 kg/m³. Enter the value for your waste.
5. Access
- Site access: Select Easy (wide road, direct access), Medium (restricted), or Tight (long reach or small lorry required). Tight access reduces the effective lorry size to 8 yd³.
6. Pricing
- Price per load: Enter the local all-in price per load, including hire, transport, and disposal.
- Extra loads beyond estimate: Enter the number of extra loads to add as a margin for unpredictable volumes. The default is 0.
Once you enter all values, the calculator instantly displays:
- Waste volume (in place)
- Loose waste volume
- Total mass (in place)
- Lorry size (yd³)
- Lorry volume (m³)
- Loads by volume
- Loads by weight (if weight limit enforced)
- Total loads required
- Grab lorry hire cost
- Grand total
- Cost per m³ (in place)
Understanding the Cost Components
To make the most of the calculator, it’s important to understand each component.
- Waste volume (in place): This is the volume of waste before bulking. It’s calculated as
area × depthif estimating from area, or taken directly from the direct volume input. - Loose waste volume: When waste is excavated or moved, it expands. The loose volume is calculated as
in-place volume × bulking factor. This is the volume the lorry actually has to carry. - Total mass (in place): This is the weight of the waste in its in-place state, calculated as
in-place volume × density / 1000in tonnes. It’s for reference only; the lorry payload check uses the loose volume and loose density. - Lorry size (yd³): The selected lorry size in cubic yards. Tight access limits the lorry to 8 yd³, even if a larger size is selected.
- Lorry volume (m³): The lorry size converted to cubic meters. 1 yd³ = 0.764554858 m³.
- Loads by volume: The number of loads required if the lorry is filled to its body volume:
ceil(loose volume / lorry volume in m³). - Loads by weight: The number of loads required if the lorry is loaded to its legal payload. It’s calculated as
ceil(loose volume / volume per load by weight), wherevolume per load by weight = (payload in kg) / (density / bulking factor). This is only calculated when weight limit is enforced and a density is entered. - Total loads required: The maximum of loads by volume and loads by weight, plus any extra loads you specify. You can’t overload the lorry, so the higher number governs.
- Grab lorry hire cost:
total loads × price per load. This is the all-in cost including hire, transport, and disposal. - Cost per m³ (in place):
total cost / in-place volume. This helps you compare the cost of grab lorry removal with other disposal methods like skips.
Understanding these components helps you choose the right lorry size, estimate loads accurately, and negotiate with haulage companies. For more information on waste management, you can refer to Wikipedia’s article on waste management.
Example Calculations
Let’s run through a few examples to see how the calculator works in different scenarios.
Example 1: Soil Removal with Standard Grab Lorry
- Waste type: Soil / subsoil
- Volume input: Estimate from area
- Area: 30 m²
- Average depth: 0.150 m
- Bulking factor: 1.30
- Lorry size: 16 yd³
- Weight limit enforced: Yes
- Lorry payload: 16 t
- Waste density: 1700 kg/m³
- Site access: Medium
- Price per load: $350
- Extra loads: 0
Calculations:
- Waste volume (in place): 30 × 0.150 = 4.5 m³
- Loose waste volume: 4.5 × 1.30 = 5.85 m³
- Lorry volume: 16 × 0.764554858 = 12.23 m³
- Loads by volume: ceil(5.85 / 12.23) = 1
- Loose density: 1700 / 1.30 = 1307.69 kg/m³
- Volume per load by weight: 16000 / 1307.69 = 12.23 m³
- Loads by weight: ceil(5.85 / 12.23) = 1
- Total loads: max(1, 1) + 0 = 1
- Total mass (in place): 4.5 × 1700 / 1000 = 7.65 t
- Hire cost: 1 × $350 = $350
- Grand total: $350
- Cost per m³: $350 / 4.5 = $77.78
Example 2: Rubble Removal with Tight Access
- Waste type: Rubble / hardcore
- Volume input: Direct volume
- Direct volume: 12 m³
- Bulking factor: 1.40
- Lorry size: 16 yd³ (but tight access limits to 8 yd³)
- Weight limit enforced: Yes
- Lorry payload: 16 t
- Waste density: 1800 kg/m³
- Site access: Tight
- Price per load: $300
- Extra loads: 1
Calculations:
- Waste volume (in place): 12 m³
- Loose waste volume: 12 × 1.40 = 16.8 m³
- Lorry size (effective): 8 yd³ (tight access)
- Lorry volume: 8 × 0.764554858 = 6.12 m³
- Loads by volume: ceil(16.8 / 6.12) = 3
- Loose density: 1800 / 1.40 = 1285.71 kg/m³
- Volume per load by weight: 16000 / 1285.71 = 12.44 m³
- Loads by weight: ceil(16.8 / 12.44) = 2
- Total loads: max(3, 2) + 1 = 4
- Total mass (in place): 12 × 1800 / 1000 = 21.6 t
- Hire cost: 4 × $300 = $1,200
- Grand total: $1,200
- Cost per m³: $1,200 / 12 = $100
Example 3: Garden Waste with Light Density
- Waste type: Garden waste
- Volume input: Estimate from area
- Area: 100 m²
- Average depth: 0.100 m
- Bulking factor: 1.50
- Lorry size: 16 yd³
- Weight limit enforced: Yes
- Lorry payload: 16 t
- Waste density: 500 kg/m³
- Site access: Easy
- Price per load: $250
- Extra loads: 0
Calculations:
- Waste volume (in place): 100 × 0.100 = 10 m³
- Loose waste volume: 10 × 1.50 = 15 m³
- Lorry volume: 16 × 0.764554858 = 12.23 m³
- Loads by volume: ceil(15 / 12.23) = 2
- Loose density: 500 / 1.50 = 333.33 kg/m³
- Volume per load by weight: 16000 / 333.33 = 48 m³
- Loads by weight: ceil(15 / 48) = 1
- Total loads: max(2, 1) + 0 = 2
- Total mass (in place): 10 × 500 / 1000 = 5 t
- Hire cost: 2 × $250 = $500
- Grand total: $500
- Cost per m³: $500 / 10 = $50
These examples show how different waste types, densities, and access conditions affect the number of loads and total cost.
Benefits of Using the Grab Lorry Sizing Calculator
Tips for Accurate Grab Lorry Sizing
- Measure the waste volume accurately: For irregular piles, measure the base area and average height. For excavated material, use the in-place volume from your excavation plans.
- Choose the right bulking factor: Soil bulks less than clay or rubble. Typical factors: soil 1.20–1.30, rubble 1.35–1.50, garden waste 1.40–1.60.
- Know your waste density: Density determines whether the lorry cubes out (fills by volume) or weighs out (hits payload limit). Soil is heavy (1700 kg/m³), garden waste is light (500 kg/m³), and general waste is very light (200 kg/m³).
- Check weight limits: Grab lorries have a legal payload, usually 16 t. Heavy waste like soil and rubble may reach the payload limit before filling the body.
- Assess site access: Tight access limits the lorry size to 8 yd³. If your site has narrow roads, low bridges, or long reaches, a smaller lorry may be required.
- Add extra loads: Volumes are estimates. Adding one extra load as a margin prevents return trips and delays.
- Compare with skips: Grab lorries are often more cost-effective for large volumes, but skips may be cheaper for small amounts. Use our Skip Hire Sizing Calculator to compare.
- Check local regulations: Some waste types require special handling or permits. Check with your local authority before booking.
For more information on grab lorries and waste removal, you can refer to resources like Wikipedia’s article on waste collection or guidelines from the Environmental Protection Agency.
How to Reduce Grab Lorry Costs
If your estimate is higher than expected, here are some ways to reduce costs:
- Separate waste types: Recyclable materials like metal and concrete may be accepted at lower rates or for free.
- Reuse material on site: Use soil for backfilling or landscaping to reduce the volume to be removed.
- Choose the right lorry size: Larger lorries are more efficient per m³, but only if access allows.
- Minimize bulking: Compact or store waste efficiently to reduce loose volume.
- Negotiate rates: For multiple loads, ask for a volume discount.
- Schedule efficiently: Combine waste removal with other site work to reduce mobilisation costs.
- Avoid contamination: Keep waste streams separate to avoid expensive mixed-waste disposal fees.
Frequently Asked Questions (FAQ)
Conclusion
The Grab Lorry Sizing Calculator is an essential tool for anyone planning waste removal. It helps you estimate the number of loads, choose the right lorry size, and budget accurately. By following the tips in this article and using the calculator, you can confidently plan your muck away project. Don’t forget to explore our other hauling calculators for all your sitework needs.
Whether you’re removing a small pile of soil or clearing a large site, accurate grab lorry sizing is key to a successful project. Try the Grab Lorry Sizing Calculator today and take the guesswork out of your waste removal budget.
2 Comments