Gravel is one of the most popular landscaping materials in the UK, used for driveways, paths, borders and decorative features. Whether you're planning a new gravel driveway or refreshing garden paths, calculating the right quantity prevents costly over-ordering or frustrating shortfalls mid-project.
This guide covers UK gravel types, supplier costs for 2025, the calculations you need to get the right amount, and tips for choosing between bulk bags and loose delivery for your project.
Gravel Calculation Formula
Weight (tonnes) = Volume (m³) × Density (typically 1.5-1.8)
Example: Gravel Driveway
Dimensions: 10m × 3m × 0.05m (50mm deep)
Volume = 10 × 3 × 0.05 = 1.5 m³
Weight: 1.5 × 1.6 = 2.4 tonnes
Bulk bags (850kg): 2.4 ÷ 0.85 = 3 bags
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Recommended Depths
| Application | Depth | Notes |
|---|---|---|
| Decorative path | 30-40mm | Pedestrian only |
| Garden path | 40-50mm | Regular use |
| Driveway (top layer) | 50-75mm | Over MOT Type 1 |
| Drainage layer | 150-300mm | Under paving |
| Sub-base (MOT Type 1) | 100-150mm | Compacted |
Aggregate Densities
| Material | Density (t/m³) | Typical Use |
|---|---|---|
| Pea gravel (10mm) | 1.5 | Paths, decorative |
| Decorative gravel (20mm) | 1.5 | Driveways, borders |
| MOT Type 1 | 1.8-2.0 | Sub-base |
| Sharp sand | 1.6 | Laying paving |
| Building sand | 1.5 | Mortar, rendering |
| Slate chippings | 1.4 | Decorative mulch |
Bulk Bag Coverage
Standard bulk bag = 850-1000kg (approx 0.5 m³)
| Depth | One Bag Covers |
|---|---|
| 30mm | 16-17 m² |
| 40mm | 12-13 m² |
| 50mm | 10 m² |
| 75mm | 6-7 m² |
Gravel Prices UK 2025
| Type | Bulk Bag | Per Tonne (loose) | Best For |
|---|---|---|---|
| Pea gravel (10mm) | £55-75 | £45-60 | Paths, children's play |
| Cotswold chippings | £65-85 | £55-70 | Traditional gardens |
| Golden gravel (20mm) | £60-80 | £50-65 | Driveways, borders |
| MOT Type 1 | £45-60 | £35-50 | Sub-base only |
| Slate chippings | £75-110 | £65-90 | Modern gardens |
| Limestone chippings | £50-70 | £40-55 | Driveways, paths |
Prices include VAT. Delivery typically £20-50 depending on location and quantity.
UK Gravel Suppliers
| Supplier | Type | Notes |
|---|---|---|
| Wickes, B&Q | Bulk bags | Convenient, higher prices |
| Buildbase, Jewson | Trade supplies | Better prices for bulk |
| Local quarries | Loose tipper loads | Best value over 5 tonnes |
| Decorative Aggregates | Online specialists | Wide range, delivery UK-wide |
Gravel Driveway Costs UK
Total Project Cost Example
Driveway size: 30m² (10m × 3m)
MOT Type 1 sub-base (150mm): 8 tonnes × £40 = £320
Decorative gravel (50mm): 2.4 tonnes × £55 = £132
Membrane: £30
Edging (26 linear metres): £150
Total materials: £632
With professional laying: £1,200-1,800 total
Methodology: How Gravel Calculations Work
Accurate gravel calculation requires understanding the relationship between volume, density, and the compaction characteristics of different aggregate types. Getting this right saves money and prevents the frustration of running short mid-project or paying for disposal of excess material.
Volume Calculation for Regular Shapes
For rectangular areas, the calculation is straightforward: length x width x depth, all in metres. However, most real-world projects involve irregular shapes. The best approach for irregular areas is to divide them into approximate rectangles or triangles, calculate each section separately, and sum the results. For curved paths, approximate the centreline length and multiply by the average width. For circular areas (such as around a tree or decorative feature), use the formula: pi x radius squared x depth.
Triangle: 0.5 x Base x Height x D = Volume (m3)
Circle: 3.14159 x r2 x D = Volume (m3)
Weight: Volume (m3) x Density (t/m3) = Weight in tonnes
Understanding Density Variation
The density of aggregate varies significantly depending on the material, particle size, moisture content, and degree of compaction. A cubic metre of dry pea gravel weighs approximately 1,500 kg, but the same volume of wet, compacted MOT Type 1 can weigh over 2,000 kg. When suppliers quote prices per tonne, the volume you receive for your money depends heavily on the density of the specific product. Always ask suppliers for the specific density of the product you are ordering, rather than relying on generic figures.
Compaction Factor
Loose gravel compacts by approximately 10-15% when walked on or driven over. Angular materials (such as MOT Type 1 limestone) compact more than rounded materials (such as pea gravel) because the irregular shapes interlock more tightly. When calculating sub-base requirements, you should increase your calculated volume by 20-30% to account for compaction. For decorative top layers, a 10% addition is usually sufficient. This compaction factor is separate from the general "order 5-10% extra" recommendation, which accounts for spillage, uneven surfaces, and wastage.
Void Ratio
Gravel is not solid - the spaces between particles (voids) typically account for 30-40% of the total volume. This is why a cubic metre of solid rock weighs approximately 2,600 kg, but a cubic metre of crushed rock gravel weighs only 1,500-1,800 kg. The void ratio also explains why water drains freely through gravel, making it an excellent material for drainage layers and Sustainable Drainage Systems (SuDS).
UK-Specific Context
Gravel projects in the UK are subject to specific planning regulations, environmental considerations, and market conditions that differ from other countries.
Planning Permission for Gravel Driveways
Under UK planning law, you generally do not need planning permission to gravel an existing driveway, provided the surface is permeable (which gravel naturally is). However, since October 2008, any new impermeable hard surface over 5 square metres at the front of a property in England requires planning permission unless it drains to a lawn or border within the property. Gravel on a permeable membrane is classified as permeable paving and is exempt from this requirement, making it an attractive option for homeowners wishing to avoid planning applications.
The Aggregates Levy
The UK charges an Aggregates Levy of £2.08 per tonne (as of 2025/26) on virgin aggregate extracted from the ground. This tax was introduced in 2002 to encourage the use of recycled and alternative materials. It applies to sand, gravel, and crushed rock. The levy is included in the prices quoted by suppliers but explains why recycled aggregates (such as crushed concrete or reclaimed stone) can be 15-25% cheaper than virgin materials for sub-base applications.
Delivery Logistics in the UK
Most UK aggregate deliveries are made by 6-wheel or 8-wheel tipper lorries, which carry approximately 10-20 tonnes per load. For smaller quantities, bulk bags (typically 850 kg to 1 tonne) are delivered on flatbed lorries with hiab cranes and placed in your chosen location. Delivery costs vary significantly by region: urban areas with good road access may see delivery charges of £20-30 per bulk bag, while remote rural areas can pay £50-80. For large projects (over 5 tonnes), loose delivery by tipper is almost always more cost-effective per tonne than bulk bags.
UK Gravel Types and Sources
The UK's diverse geology produces a wide range of decorative aggregates. Popular regional choices include Cotswold chippings (warm golden limestone, sourced from the Cotswolds and widely available across central and southern England), Scottish granite (grey and pink varieties, extremely durable), Staffordshire pink gravel (distinctive reddish-pink colour), Derbyshire gold (warm amber limestone), and Welsh slate chippings (dark blue-grey, contemporary appearance). Locally sourced materials are generally cheaper due to lower transport costs and have a lower carbon footprint, making them the environmentally preferable choice where aesthetics allow.
SuDS and Building Regulations
Sustainable Drainage Systems (SuDS) are increasingly important in UK construction and landscaping. Gravel driveways and paths naturally qualify as permeable surfaces under SuDS principles, allowing rainwater to infiltrate the ground rather than running off into storm drains. Many local authorities now require SuDS compliance for new developments, and gravel is one of the simplest ways to achieve this. A properly constructed gravel driveway with a sub-base can handle rainfall intensities well above the typical UK maximum of 50 mm per hour.
Worked Examples
Example 1: Garden Path
Dimensions: 12m long x 1m wide x 40mm deep
Volume: 12 x 1 x 0.04 = 0.48 m3
Weight (pea gravel, density 1.5): 0.48 x 1.5 = 0.72 tonnes
Plus 10% extra: 0.72 x 1.1 = 0.79 tonnes
Bulk bags needed: 1 bag (850 kg) will be sufficient with a small amount left over
Estimated cost: 1 bulk bag of pea gravel (£55-75) + delivery (£25-40) = approximately £80-115 total
Example 2: Double Driveway (Full Build)
Dimensions: 8m x 5m = 40 m2
Sub-base (MOT Type 1, 150mm compacted):
Volume: 8 x 5 x 0.15 = 6.0 m3 (loose) + 25% compaction factor = 7.5 m3
Weight: 7.5 x 1.9 = 14.25 tonnes
Decorative top layer (golden gravel 20mm, 50mm deep):
Volume: 8 x 5 x 0.05 = 2.0 m3 + 10% = 2.2 m3
Weight: 2.2 x 1.5 = 3.3 tonnes
Total materials cost estimate:
MOT Type 1: 14.25 tonnes x £42/tonne (loose delivery) = £599
Golden gravel: 4 bulk bags x £65 = £260
Membrane (40 m2): £45
Timber edging (26 linear metres): £180
Total materials: approximately £1,084
Example 3: Circular Feature Around a Tree
Outer radius: 1.5m, Inner radius (trunk protection): 0.3m
Depth: 50mm of slate chippings
Area: pi x (1.5 squared - 0.3 squared) = 3.14159 x (2.25 - 0.09) = 6.79 m2
Volume: 6.79 x 0.05 = 0.34 m3
Weight (slate, density 1.4): 0.34 x 1.4 = 0.476 tonnes
One bulk bag of slate chippings (£75-110) will cover this area with material to spare.
Common Mistakes and Tips
Frequently Asked Questions
How long does a gravel driveway last in the UK?
A properly constructed gravel driveway with a compacted sub-base and membrane can last 15-25 years before needing significant refurbishment. The sub-base itself may last indefinitely. However, the decorative top layer will need periodic topping up - typically every 3-5 years - as material is displaced by traffic, washed by rain, or compacted into the sub-base. Budget approximately one bulk bag per 10-15 m2 every 3-4 years for maintenance top-ups.
Is gravel cheaper than block paving for a driveway?
Significantly so. A gravel driveway typically costs £40-60 per m2 installed (including sub-base, membrane, edging, and decorative gravel), compared to £70-120 per m2 for block paving. For a 30 m2 driveway, that represents a saving of approximately £900-1,800. However, block paving requires virtually no maintenance, while gravel needs periodic raking and top-ups. Over 20 years, the total cost of ownership is closer, but gravel still tends to be the more economical choice.
Can I lay gravel myself or do I need a professional?
Gravel is one of the most DIY-friendly landscaping materials. For paths and decorative areas, it is straightforward: prepare the ground, lay membrane, install edging, and spread gravel. Driveways are more demanding because the sub-base must be properly compacted (ideally with a vibrating plate compactor, available for hire from approximately £30-50 per day from UK hire companies like HSS or Jewson). The most physically demanding part is moving the material - one tonne of gravel is approximately 0.6 cubic metres, and shifting it by wheelbarrow from delivery point to final location requires significant effort.
What is the difference between gravel and shingle?
In UK terminology, gravel typically refers to angular crushed stone (e.g., limestone chippings, granite chippings), while shingle refers to naturally rounded stones, usually sourced from riverbeds or beaches. Shingle is more comfortable to walk on and has a more natural appearance, but it is less stable underfoot and under vehicle tyres because the rounded particles do not interlock. Angular gravel is generally preferred for driveways and functional paths, while shingle is often chosen for decorative garden features and Japanese-style gardens.
James Mitchell, ACCA
Chartered Accountant & Former HMRC Advisor
James is a Chartered Certified Accountant (ACCA) specialising in UK personal taxation and financial planning. With over 12 years in practice and a background as a former HMRC compliance officer, he brings authoritative insight to complex tax topics.