Type 1 Sub Base Explained: Why Your New Driveway or Patio Needs It (and How to Get It Delivered in Scotland)

A new driveway, patio or garden path needs more than an attractive surface. It needs a firm, prepared layer underneath to help support that surface and keep it stable.

Type 1 sub base is commonly used for this purpose. If you are planning groundwork, it helps to know what the material does, how much you may need and how it should be laid. You will also need to organise delivery to a practical spot on site.

What is a Type 1 sub base?

Type 1 is a graded crushed aggregate made up of different stone sizes, including smaller particles, or “fines”. When spread and compacted, the pieces lock together to form a dense, stable base.

It is used beneath surfaces such as block paving, slabs, tarmac and concrete. Type 1 is not the finished surface or the bedding layer; it sits below them and provides support.

It is also different from clean, open drainage stone. Type 1 contains fines and compacts tightly. If your design needs a free-draining layer, check the specification before ordering.

Why the sub-base matters

A surface laid over weak or poorly prepared ground can move, settle or become uneven. A correctly prepared sub-base helps spread the load and gives the finished surface a more consistent foundation.

That matters for different reasons across a project:

• Driveways: the base needs to support vehicles as well as the paving or surface above it.

• Patios and paths: a stable layer helps reduce movement under everyday foot traffic.

• Shed bases: a level, firm foundation helps support the structure.

• Extensions and other building work: the required construction may be set by drawings or a designer’s specification.

A sub-base cannot compensate for every ground problem. Soft, wet or unstable ground may need extra preparation or a different design.

How deep should Type 1 be?

The right depth depends on what you are building, the ground beneath it and the loads it will carry. Depths below are useful starting points for domestic planning, not a substitute for a project specification.

• Paths and patios: around 75–100 mm of compacted Type 1 is a common planning range.

• A typical car driveway: around 150 mm compacted on firm ground is a common starting point.

• Soft or wet ground, heavier vehicles or frequent manoeuvring: you may need a deeper sub-base or additional ground preparation.

These are compacted depths. Loose aggregate takes up more space before it is compacted, so do not base your order on the finished depth alone. For extensions or work with construction drawings, follow the specified design rather than a general domestic guide.

For further guidance, see NHBC standards for drives, paths and landscaping and Pavingexpert’s sub-base FAQ. Ground conditions and the requirements of your paving system still need to be considered.

Preparing and laying the base

The exact method depends on the project, but the basic sequence is straightforward:

1. Set the levels. Work out the finished height and allow for the surface, bedding and sub-base. Plan how rainwater will drain.

2. Excavate and prepare the ground. Remove topsoil, organic material and unsuitable soft spots. The exposed formation should be suitable for the work before Type 1 goes down.

3. Spread the aggregate in layers. Avoid tipping one deep layer and expecting a small compactor to consolidate it fully.

4. Compact each layer. Use suitable compaction equipment and follow the project specification. The finished sub-base should be firm and even before the bedding and surface are installed.

If you uncover very soft or waterlogged ground, pause and reassess before building over it. A contractor or designer can help confirm whether the depth or preparation needs to change.

Estimate how much you need

Start with the length and width of the area, then multiply the area by the planned compacted depth to estimate the volume. For example, a 20 m² area with a planned compacted depth of 0.15 m gives a volume of 3 m³ after compaction.

That is a volume estimate, not a final tonnage. The quantity you order can depend on the material and how it settles during placement and compaction. If you are unsure, tell us the area, the planned depth and what you are building. We can discuss the quantity before you arrange delivery.

Our aggregate delivery service has a minimum order of 5 tonnes. We can supply Type 1 and other listed aggregates, subject to availability and the agreed requirements.

Get Type 1 delivered where the work is happening

A bulk delivery can save you handling individual bags or arranging several smaller loads. We deliver quarry-sourced aggregate to sites across Glasgow, Ayrshire, Lanarkshire, Falkirk and West Lothian.

Tell us your postcode, the quantity you are considering and where on site you need the material. We will check the delivery arrangement, access and availability. The exact drop location depends on the vehicle’s position, safe working conditions and reach, so include any relevant details when you enquire.

Before booking, check that there is room for the vehicle and that the ground can take its weight. Our grab lorries are approximately 9.5 m long and 2.6 m wide. Height is approximately 3.7 m when empty and can reach around 4.9 m when fully loaded. Low branches, cables, narrow entrances, parked vehicles or weight restrictions may affect access.

A full grab-hire load can carry up to 16 tonnes. Actual usable capacity depends on the material and job requirements.

Have soil to remove as well?

If your project involves digging out old ground, you may need aggregate brought in and suitable excavated material taken away. We can discuss arranging Type 1 delivery and accepted soil collection on the same agreed visit.

This can avoid a separate aggregate transport charge where the delivery fits the agreed collection visit, subject to quantities, vehicle capacity and access. Material and collection charges still apply. Any extra journey needs a separate agreed price.

Tell us what you need delivered and what the excavated material contains. We will confirm whether the material can be accepted and whether one visit is practical.

Prices and getting an estimate

Grab-hire prices start at £220 + VAT for a typical load. This is a starting floor for grab hire, not an aggregate delivery price. Prices can only be higher, depending on factors such as location, access and disposal requirements.

You can get a free estimate in seconds through our online quote page. An estimate is not a confirmed booking. We check the job details and availability before an arrangement is agreed. Same-day or next-day service may be possible, subject to availability and access.

What to include in your enquiry

To help us assess your request, send:

• Your site postcode.

• The material and quantity you need delivered.

• The area and planned compacted depth, if known.

• Your preferred delivery day.

• Access details, including narrow entrances, overhead obstructions or restricted standing space.

• Details of any soil or other accepted material you want collected at the same visit.

If you are new to groundwork, you do not need to have every measurement ready. Share what you know and ask us about the next step. We will confirm the practical details before a booking is agreed.

Tell us what you’re building, where the site is and what you need delivered.Request a free estimate, or read more about combined aggregate delivery and soil collection.