An eight-wheel grab lorry can typically carry approximately 14 to 16 tonnes, or around 10 to 12 cubic metres by volume. However, the number of loads you need depends on the type, density and moisture content of your waste.
A pile of wet clay will reach the lorry’s legal weight limit much sooner than a similarly sized pile of branches or light mixed waste. Excavated soil also expands when removed from the ground, so the loose pile can be considerably larger than the original hole.
The most reliable way to estimate your requirements is to provide:
- Photographs of the complete pile
- Approximate length, width and height
- A description of every material
- The dimensions of the excavation, if applicable
- Details of whether the material is wet
- Your collection postcode
- Access photographs
We can then estimate whether the job is likely to require one load, several loads or a smaller vehicle.
Quick Grab-Lorry Load Guide
| Waste quantity or project | Possible number of eight-wheel loads |
|---|---|
| Small pile of soil or rubble | Part load or 1 load |
| Moderate garden excavation | Approximately 1 load |
| Small extension foundation excavation | Approximately 1–2 loads |
| Medium rear extension | Approximately 2–4 loads |
| Large driveway excavation | Approximately 2–4 loads |
| Major landscaping project | Approximately 3–6 loads |
| Basement excavation | Several to many loads |
| Commercial groundworks | Calculated from project quantities |
These are broad estimates only. Excavation depth, soil conditions and project size can produce substantial differences.
How Much Does One Grab Lorry Hold?
A standard eight-wheel grab lorry can usually carry:
- Approximately 14 to 16 tonnes
- Around 10 to 12 cubic metres by physical volume
- Roughly three or four large skips’ worth of suitable heavy waste
The lorry has both a volume limit and a legal weight limit.
Dense materials normally reach the weight limit before the vehicle body is full. Lighter materials may fill the body before reaching the maximum payload.
Read our guide to how much waste a grab lorry can carry for a detailed explanation.
Weight Versus Volume
Waste can be measured by weight in tonnes or by volume in cubic metres.
These measurements are connected, but they are not interchangeable without knowing the material’s density.
For example:
- Wet clay is very dense
- Dry topsoil is generally lighter
- Concrete is extremely heavy
- Broken rubble contains air gaps
- Green waste is relatively light but bulky
- Mixed construction waste has an unpredictable density
- Timber may occupy considerable space without much weight
Two piles with identical dimensions may therefore require different numbers of loads.
How to Measure a Waste Pile
Measure the pile’s approximate:
- Length
- Width
- Average height
Use the formula:
Length × width × height = approximate volume in cubic metres
For example, if a pile is:
- 5 metres long
- 2 metres wide
- 1 metre high
the estimated volume is:
5 × 2 × 1 = 10 cubic metres
This does not automatically mean it will fit into one load. If the pile consists of very wet clay or dense concrete, it may exceed the lorry’s legal payload.
If it consists of branches or light mixed waste, it may fit by weight but use most of the available body volume.
How to Measure an Irregular Pile
Most waste piles are not perfect rectangles.
To estimate an uneven or sloping pile:
- Measure its maximum length
- Measure its maximum width
- Estimate its average rather than maximum height
- Multiply the three figures
- Send photographs so the shape can be assessed
For a roughly triangular pile, using the maximum height will usually overestimate the volume. The average height may be around half to two-thirds of the highest point, depending on the shape.
It is safer to provide slightly generous measurements than to underestimate the waste and discover that an additional load is required.
How Many Loads of Soil Will I Need?
Soil collections are usually limited by weight.
An eight-wheel grab lorry may carry approximately 14 to 16 tonnes of suitable soil, but the volume represented by that weight depends on:
- Soil type
- Clay content
- Moisture
- Stones
- Organic content
- Compaction
- Contamination
A broad planning estimate might place one full soil load at approximately 8 to 10 loose cubic metres, but wet clay or unusually dense material may produce a lower volume.
Dry, lighter soil may occupy more space before reaching the same weight.
Send photographs and explain whether the material is topsoil, subsoil, clay or mixed excavation spoil.
Why Excavated Soil Expands
Soil is compacted while it remains in the ground. Digging breaks up that compacted structure and introduces air spaces between particles.
This increase in volume is known as bulking or swell.
Depending on the ground conditions, a preliminary allowance of approximately 20% to 40% may be used when converting compacted excavation volume into loose spoil. Actual expansion can fall outside this range.
For example, an excavation containing 10 cubic metres of compacted ground could produce approximately 12 to 14 cubic metres of loose soil.
The weight has not increased. The material simply occupies more space after excavation.
This is one of the most common reasons customers underestimate the number of loads required.
Example: Garden Excavation
Imagine a garden area measuring:
- 8 metres long
- 4 metres wide
- 0.25 metres deep
The compacted excavation volume is:
8 × 4 × 0.25 = 8 cubic metres
Allowing for the soil to expand after excavation, the loose quantity could be approximately 9.6 to 11.2 cubic metres.
Depending on the soil type and moisture content, this might require one full eight-wheel load or possibly an additional part load.
If the ground is wet clay, the weight limit may be reached before all the loose material has been collected.
Example: Extension Foundations
Suppose the total foundation trenches measure:
- 30 metres in combined length
- 0.6 metres wide
- 1 metre deep
The compacted volume is:
30 × 0.6 × 1 = 18 cubic metres
After allowing for bulking, the excavation could produce around 22 to 25 cubic metres of loose spoil.
This may require approximately three eight-wheel soil loads, depending on the ground conditions and how much material is retained on site.
The excavation may produce even more waste if the project also includes:
- Ground-floor reduction
- Drainage trenches
- Oversite excavation
- Patio removal
- Existing concrete foundations
- Landscaping changes
Example: Driveway Excavation
A driveway measuring:
- 10 metres long
- 4 metres wide
- 0.3 metres average excavation depth
has a compacted volume of:
10 × 4 × 0.3 = 12 cubic metres
The waste could include:
- Paving
- Tarmac
- Concrete
- Sub-base
- Soil
- Clay
After allowing for loose volume and separating the materials, the project may require approximately two or three loads.
The exact requirement depends on the construction of the existing driveway and whether any reusable hardcore remains on site.
How Many Loads of Rubble Will I Need?
Rubble varies according to the size and shape of the pieces.
A pile may contain:
- Bricks
- Blocks
- Tiles
- Mortar
- Stone
- Paving
- Broken concrete
- Air spaces between larger pieces
An eight-wheel grab lorry can generally carry around 14 to 16 tonnes of suitable rubble or hardcore.
A loosely stacked pile of large bricks may occupy more volume than the same material after crushing. Dense concrete, meanwhile, can reach the legal weight limit while the lorry still has visible space.
Breaking large sections into manageable pieces allows more efficient loading.
How Many Loads of Concrete Will I Need?
Concrete is extremely dense, so collections are normally limited by weight.
One eight-wheel grab lorry may carry approximately 14 to 16 tonnes of broken concrete. The actual volume can be significantly lower than the full physical capacity of the body.
Tell the operator if the pile includes:
- Reinforced concrete
- Oversized slabs
- Foundation sections
- Concrete mixed with soil
- Kerbstones
- Metal reinforcement
Large or reinforced pieces may need mechanical breaking before collection.
How Many Loads of Garden Waste Will I Need?
Garden waste can range from heavy soil to lightweight vegetation.
A garden-clearance pile containing mainly:
- Soil
- Turf
- Clay
- Stones
- Roots
will usually be limited by weight.
A pile containing mainly:
- Branches
- Leaves
- Hedge cuttings
- Shrubs
- Plants
will normally be limited by volume.
Cutting down branches and separating soil from green waste can improve loading efficiency and make the disposal route easier to price.
Large tree trunks and stumps should be declared before collection.
How Many Loads of Mixed Construction Waste Will I Need?
Mixed construction waste is difficult to estimate because different materials occupy space differently.
It may contain:
- Timber
- Plastic
- Packaging
- Insulation
- Metal
- Rubble
- General building waste
One part of the pile may be dense while another is light and bulky.
Mixed waste often fills the lorry body before reaching the maximum payload. It also costs more to process than clean, separated soil or hardcore.
For a more accurate estimate:
- Separate recyclable materials
- Flatten packaging
- Cut long timber into manageable sections
- Remove prohibited items
- Keep plasterboard separate
- Send photographs of every pile
Will One Load Be Enough?
One eight-wheel load may be sufficient for:
- A moderate pile of soil
- A small foundation excavation
- A domestic patio removal
- A modest driveway project
- Renovation rubble
- A substantial garden clearance
- Several large skips’ worth of heavy waste
One load is less likely to be sufficient for:
- A large rear extension
- Deep foundation trenches
- A complete front-and-rear garden excavation
- A basement
- Major demolition
- Commercial groundworks
- A large development site
- Extensive wet-clay removal
If the estimate is close to the lorry’s capacity, it is sensible to plan for the possibility of a small remaining quantity.
Why a Lorry May Leave Before It Looks Full
The lorry does not need to be physically full to have reached its capacity.
It may leave with visible space because:
- The legal payload has been reached
- The waste is unusually dense
- The soil is wet
- Weight distribution must remain safe
- Material must stay below the body’s safe fill level
- Adding more would exceed an axle-weight limit
The driver cannot continue loading simply because space appears to remain in the body.
Can I Book Half a Load?
Part-load collections may sometimes be available, depending on the material, location and operator’s schedule.
However, half a load will not always cost exactly half the price of a full load.
Every collection still includes:
- Vehicle travel
- Driver time
- Loading
- Fuel
- Disposal administration
- Waste documentation
- Minimum facility charges
If you have a small quantity, send photographs and ask whether it can be combined with another suitable local collection.
Is It Better to Overestimate?
It is better to allow a sensible margin than to underestimate significantly.
Underestimating can cause:
- Material being left behind
- An unplanned additional collection
- Delays to excavation or construction
- Extra vehicle movements
- Disruption to neighbours
- Rebooking costs
- Programme delays
However, booking several full loads without evidence is also unnecessary.
Use measurements and photographs to create a realistic working estimate, then update the operator if the quantity changes.
How Multiple Loads Are Scheduled
For larger projects, several collections can be arranged in sequence.
The programme may involve:
- The first lorry arriving and loading
- The full vehicle travelling to an authorised facility
- Another vehicle arriving or the same lorry returning
- Excavation continuing between collections
- Final clearance after the main muck-away operation
The most efficient approach depends on:
- Number of loads
- Site storage space
- Distance to the receiving facility
- Excavator availability
- Local traffic
- Road restrictions
- Working-hour conditions
- Vehicle availability
Large projects should be planned in advance rather than booking each load only after the previous vehicle has left.
How to Reduce the Number of Loads
Keep soil and rubble separate
This improves recycling and prevents the entire quantity being treated as mixed waste.
Reuse suitable material on site
Clean hardcore may be suitable for an approved sub-base or fill application. This should be agreed with the project designer or building professional.
Avoid mixing bulky waste
Timber and packaging can occupy space that could otherwise be used for dense material.
Break down large pieces
Smaller concrete and masonry sections can be loaded more efficiently.
Cut branches into shorter lengths
This reduces empty spaces in green-waste loads.
Protect soil from excessive water
Wet soil becomes heavier and may reduce the volume carried per load.
Give the operator accurate information
Sending complete photographs and measurements helps the correct vehicles and schedule to be arranged.
Information Needed for an Accurate Estimate
Provide:
- Collection postcode
- Waste type
- Pile length
- Pile width
- Average pile height
- Excavation dimensions
- Soil type, if known
- Whether the material is wet
- Photographs of the complete pile
- Photographs of access
- Details of walls, fences and cables
- Whether more waste will be produced
- Your preferred collection date
For excavation work, include both the hole dimensions and photographs of the loose spoil if digging has already started.
Do Not Mix Prohibited Waste Into the Pile
The load estimate assumes the material can be collected through an ordinary non-hazardous waste route.
Do not include:
- Asbestos
- Contaminated soil
- Paint
- Oil
- Chemicals
- Batteries
- Gas cylinders
- Electrical equipment
- Fridges
- Tyres
- Clinical waste
Plasterboard and upholstered furniture also require separate handling.
See our guide to what can and cannot go in a grab lorry before finalising the pile.
Prepare the Waste Before Collection
For an efficient collection:
- Put the waste into one accessible pile
- Keep materials separated
- Move parked vehicles
- Check overhead cables
- Open and secure gates
- Break down oversized material
- Keep the lorry’s working area clear
- Update the operator if the pile changes
Our grab-lorry collection preparation guide contains a complete checklist.
Get a Grab-Lorry Load Estimate
You do not need to calculate the exact tonnage yourself.
Send Grab Lorries Hire:
- Your postcode
- Clear photographs or a video
- Pile measurements
- Excavation dimensions
- A description of every material
- Access photographs
- Your preferred collection date
We will assess the likely quantity and advise whether you may need one load, a part load or several collections.
We provide grab lorry hire across London and the surrounding Home Counties, with same-day and next-day availability subject to location and vehicle capacity.
Call 020 3355 9233 or request a free quote online.
Frequently Asked Questions
How much soil fits in one grab lorry?
An eight-wheel grab lorry can typically carry around 14 to 16 tonnes of soil. Depending on density and moisture, this may represent approximately 8 to 10 loose cubic metres.
How many grab loads equal 20 cubic metres of soil?
Twenty cubic metres of loose soil may require approximately two or three loads. Dense or wet material may require more capacity by weight.
How many grabs will I need for an extension?
A small extension may produce one or two loads, while a medium or large extension can produce several. Foundation depth, ground-floor excavation and soil conditions all affect the quantity.
How many grab loads will I need for a driveway?
A typical domestic driveway excavation might require approximately two or three loads, but size, excavation depth and existing construction vary significantly.
How do I calculate cubic metres?
Multiply the approximate length, width and average height of the waste pile. Measure in metres to obtain cubic metres.
Does excavated soil increase in volume?
Yes. Compacted soil expands when excavated. A preliminary bulking allowance of around 20% to 40% may be used, although the actual figure depends on the ground.
Why did my waste need more loads than expected?
Common reasons include soil bulking, wet clay, deeper excavation, hidden foundations, inaccurate measurements or additional waste being added.
Can photographs provide an exact load estimate?
Photographs provide a useful estimate, especially with measurements, but they cannot guarantee the exact weight or density.