Why is there no single answer to how thick block paving should be?
Because the thickness of the pavers is only one part of a layered system, and each layer is chosen for the job it has to do. A paver that performs well on a quiet drive used by two cars can rock and break under a reversing delivery lorry if the material beneath it is too thin or too wet. Asking how thick block paving should be is really asking what will travel over it and what the ground can carry.
On the Costa del Sol we see three broad situations: private villa driveways and garage entrances used by cars, shared access roads and car parks in urbanizaciones where vans, refuse trucks and removal lorries turn, and industrial yards with forklifts and articulated vehicles. The same paving pattern can look identical in all three, yet the structure hidden underneath should be quite different in each case.
What are the layers under a block-paved driveway?
A block-paved driveway is built from the bottom up in distinct layers, each compacted or levelled before the next goes on. Understanding what each layer does makes it much easier to compare quotes and to see where corners are sometimes cut on cheaper jobs.
- Formation: the natural ground once topsoil, roots and soft material are dug out; it must be firm and shaped to the final falls.
- Sub-base (zahorra): a graded crushed aggregate spread in layers and compacted with a plate or roller; it spreads wheel loads and lets the ground breathe.
- Bound layer (suelo-cemento or concrete slab): added where traffic is heavy, the ground is poor or a stiffer platform is needed under turning wheels.
- Laying course: a bed of fine grit screeded to level, on which the pavers sit; it is not meant to correct a badly shaped base.
- Pavers and joints: concrete blocks laid in an interlocking pattern, compacted into the bed and filled with jointing material.
- Edge restraint: kerbs or a haunched edge that stop the whole surface from creeping outwards.
Our own block-paving work for private drives follows this order on every job, and the detail of each layer is explained on the pillar site in the guide to paving layers and base build-up. Where a solid concrete platform is the right answer, see concrete bases under paving.
How does the type of traffic change the sub-base?
Heavier and more frequent traffic needs a deeper, better compacted sub-base and, beyond a certain point, a bound layer. The deciding factor is not only weight but also how wheels behave: turning, braking and reversing twist the surface far more than a car rolling straight in and out.
| Use | What usually matters most | Typical build-up approach |
|---|---|---|
| Villa or townhouse drive, cars only | Firm formation, good compaction, clean edges | Granular sub-base, grit bed, standard driveway pavers |
| Garage entrance with tight turning | Twisting at the threshold, water at the door | Well-compacted sub-base, robust edge detail, a pattern that locks well |
| Community access road or car park | Service vehicles, refuse trucks, many movements | Deeper sub-base; bound layer considered on weak ground |
| Industrial yard, forklifts and lorries | Point loads, constant turning, pallets dragged | Engineer-specified layers, often bound, thicker interlocking pavers |
For private drives we set out the build-up ourselves after a site visit. For community car parks and industrial yards the client or their technical adviser often has a specification; when there is one, we build to it, and when there is none for a heavy-traffic area we recommend getting one. That is the approach on our industrial yard paving and on community car parks.
When is a concrete base better than a granular sub-base?
A concrete or cement-bound base is worth considering when the ground is weak or variable, when heavy vehicles turn on the surface, or when the drive is steep enough that a loose sub-base could migrate. It is not automatically better: it adds cost, it must be laid with falls and drainage in mind, and water must still have a way out from the grit bed above it.
A well-compacted granular sub-base remains the normal choice for most car-only villa drives. It tolerates small ground movements, it can be opened and re-closed when a service trench is needed and it drains through. A rigid slab under pavers that holds water in the bedding layer can cause more trouble than it solves, so the decision is made on site, not from a brochure.
On sloping drives the question comes up often, and the specific points are covered on our sloping driveways page, where gradient, edge detail and water speed all influence whether a bound layer is used.
How thick should the pavers themselves be?
Paver thickness should match the traffic class and the pattern: car-only drives can use standard driveway blocks, while areas with lorries or forklifts call for thicker interlocking units chosen by the specifier. We do not publish a single figure here because the right choice depends on the product range, the pattern and the base beneath it.
Concrete paving blocks sold in Spain are made and tested to UNE-EN 1338 together with the Spanish complement UNE 127338, and concrete kerbs to UNE-EN 1340 with UNE 127340. These standards define how the blocks are classified and tested; the supplier's declared values for a given product tell you whether it suits vehicle use. We ask for that information when a client supplies their own material.
The laying pattern matters as much as thickness. Herringbone and double-T interlocking shapes resist the sideways push of turning wheels better than blocks laid in straight stretcher rows, which is why yards and car parks are usually laid that way. The patterns themselves are described in the pillar guide to laying patterns.
What goes wrong when the base is too thin or poorly compacted?
A defective sub-base shows itself as ruts along the wheel lines, dips at the garage door, rocking blocks and widening joints, usually within the first seasons of use. Pavers are rarely the cause on their own; the problem almost always starts with soft formation, a sub-base laid in one thick lift instead of compacted layers, or water that softens the ground.
- Ruts in the tracks where cars always drive, while the rest stays level.
- A hollow just inside the gate or in front of the garage where vehicles brake and turn.
- Grit washing out of joints after storms, followed by loose blocks.
- Kerbs leaning outwards because the base under them was never consolidated.
- Settlement along a pipe or cable trench that was backfilled without compaction.
If your existing drive already shows these signs, the right first step is a diagnosis rather than a new surface. Our sister site explains base faults that cause sinking and handles the lift-and-relay repairs.
Who decides the specification, and what do we take responsibility for?
We are a paving contractor: we excavate, build the base, lay, cut and compact. We do not draft engineering projects or carry out geotechnical studies. For a private car-only driveway, our proposal sets out the build-up we intend to use and why, based on what we see on site and what you tell us about the vehicles.
For industrial yards, large community car parks or any area where an engineer has been appointed, we build to the layers and materials in their documents. Health and safety on any construction site in Spain follows Royal Decree 1627/1997, which applies to works with or without a project, so the site organisation is planned whatever the size of the job.
To start, send us a photo and the approximate m² – free, no-obligation quote. Tell us which vehicles use the drive, whether lorries ever deliver and whether you have noticed standing water. For a view of how build-up affects budget, the cost factors are explained on what moves the price, and you can ask about a full new drive on our driveway block paving page.
Frequently asked questions
Does a car-only villa driveway need a concrete base?
Usually not. A properly dug formation with a granular sub-base compacted in layers is the normal build for cars. A bound or concrete layer is considered when the ground is soft or variable, the drive is steep or occasional heavy vehicles are expected. We decide after seeing the ground, not by default.
Can you tell me the exact depth of sub-base from a photo?
A photo lets us understand the access, the slope and the current surface, which is enough for an initial proposal. The final depth depends on what we find once the old surface and topsoil are removed, so the build-up is confirmed on site. If the ground turns out softer than expected, we explain it before continuing.
Why do pavers in a car park need a different pattern from a garden path?
Vehicles turning and braking push the blocks sideways. Interlocking shapes such as double-T and patterns such as herringbone lock together and spread that push across many units. Straight stretcher rows look tidy on a footpath but can creep under vehicle traffic, especially at the entrance and in turning areas.
Which standard covers concrete paving blocks in Spain?
Concrete paving blocks are covered by UNE-EN 1338 and its Spanish complement UNE 127338, which define requirements and test methods. Concrete kerbs are covered by UNE-EN 1340 with UNE 127340. The supplier's declared values for a specific block show whether it is intended for vehicle use.
Can I supply my own pavers for a heavy-traffic area?
Yes, as long as the product is suitable for the traffic. We ask for the technical sheet or declared performance from the supplier and check that the thickness and shape suit the use. If the material is clearly meant for pedestrian areas, we say so before any work starts rather than laying it under lorries.
Do you carry out a geotechnical study before building the base?
No. We are the paving contractor and do not carry out geotechnical studies or draft engineering projects. On private drives we assess the ground visually and during excavation. For industrial or large community areas we recommend that the owner commissions a technician, and we build to their specification.
Is the grit bed there to level out an uneven base?
No. The laying course of fine grit is meant to be a consistent, fairly thin bed that lets each paver settle evenly. Using it to fill hollows in a badly shaped sub-base leads to uneven settlement later. The falls and levels should already be built into the sub-base before screeding.
Why does my existing drive have ruts only in the wheel tracks?
Ruts that follow the wheel lines usually point to a sub-base that was too thin, not compacted in layers or softened by water. The pavers simply follow the movement below them. Fixing it means lifting the affected area and correcting the base, which our sister site for sunken paving handles.
Does a thicker paver compensate for a weak sub-base?
Only partly, and not for long. A thicker block spreads load a little better, but if the sub-base deforms the blocks will still follow it down. Money is usually better spent on excavation, compaction and drainage than on upgrading the paver alone. Both should match the traffic.
Will you build to my engineer's specification for an industrial yard?
Yes. When an engineer or architect has specified layers, materials and levels, we build to those documents and raise any site issue with them. If no specification exists for a heavily trafficked yard, we recommend obtaining one before work starts, because we do not design pavement structures ourselves.