Why does block paving need edge restraint?
Block paving works because the units press against each other through their joints. That only happens if something solid stops the outermost blocks from moving, so kerbs and edgings are a structural part of the paving, not just a decorative border.
Every time a wheel rolls over a paved surface, it pushes the blocks slightly sideways. In the middle of the area those forces are absorbed by neighbouring blocks; at the edges, they push the last row outwards. If the edge is weak, the outer blocks drift, the joints behind them open, the jointing sand drains away and the surface gradually loosens from the outside in. Loose and rocking blocks near the borders are one of the most common faults we see on older drives.
Edge restraint is therefore installed before the blocks are laid, and it is set on concrete so that it cannot rotate or slide. The quality of the edging is one of the clearest signs of how carefully a paved area has been built.
Which types of kerb and edging are available?
The main options are raised kerbs, flush kerbs or edgings, natural stone kerbs and concealed edges formed in concrete. The choice depends on whether the edge must contain vehicles, separate levels, guide water or simply finish the paving neatly. Several types are often combined on the same job.
- Raised kerbs: stand above the paved surface to separate a drive from a lawn, a bed or a road, and to guide water along the edge
- Flush kerbs and edging units: sit level with the paving so wheels and feet can cross the boundary without a step
- Curved kerbs: special units or short sections that follow the radius of a bend or turning area
- Natural stone kerbs: granite or other stone, often chosen to match stone setts or historic surroundings
- Soldier courses: a row of pavers set on end or crosswise along the border, bedded in concrete
- Concealed concrete haunch: a hidden concrete edge behind the last row of blocks where a visible kerb is not wanted
Concrete kerbs are covered by UNE-EN 1340 with the Spanish complement UNE 127340, and natural stone kerbs by UNE-EN 1343. When kerbs are supplied for a job, these standards give a common reference for dimensions and performance. The product chosen is named in the quote, together with how it will be bedded.
How are kerbs set correctly?
Kerbs are set on a concrete bed, lined and levelled to string lines, then backed with a concrete haunch that locks them in position. The top of each kerb is checked against the finished paving level and the planned falls.
- Set out the line and level of the kerbs using pegs and string, taking account of the falls of the paving.
- Excavate a trench for the kerb and its bed, deeper than the paving build-up.
- Lay a concrete bed and bed each kerb on it, tapping it down to line and level.
- Check alignment and height with a spirit level and straightedge along the run.
- Form a concrete haunch behind the kerb, and in front of it where the paving side needs support.
- Allow the concrete to harden before compacting the sub-base or laying pavers against the kerb.
On curved sections the kerbs are cut or special radius units are used so that the curve flows without sharp steps. Joints between kerbs are kept consistent, and where kerbs meet steps, gates or drains, the details are worked out on site so water is not trapped. Our guide to layers and base shows where the kerb sits in the overall build-up.
How do kerbs help control water?
Kerbs can act as a channel edge, guiding surface water along a line to a drain, or as a barrier that stops water from flowing off the paving onto a lawn or a neighbour's land. Their height and position are decided together with the falls of the paved area.
On a drive that falls towards the road, a raised kerb along the sides keeps water within the paving and leads it to a channel or gully. In a garden, a flush edge lets water soak into adjacent planting. Where paving meets the house, the falls are set away from the wall and a kerb or channel may be needed to catch water before it reaches the door. The guide to compaction and falls explains how these decisions are made.
What if the kerb is on the public pavement?
Kerbs on the public pavement belong to the town hall. Lowering a kerb for a vehicle crossing, or altering the pavement in front of a property, needs specific municipal authorisation, under that town hall's ordinance, before any work starts.
We carry out the works on private land and, where the owner has obtained the necessary authorisation, can execute the agreed works on the boundary. We do not apply for licences on the owner's behalf. The guide to permits and rules summarises the general framework, including the responsible declaration under Law 7/2021 (LISTA) for minor works. For drives that need a new vehicle entrance, the sister site's page on garage entrances and access goes into more detail.
Can loose edges be fixed without relaying the whole area?
Often, yes. If only the border rows have drifted because the edging was missing or weak, the outer blocks can be lifted, a proper kerb or haunch installed and the blocks relaid and rejointed, leaving the sound central area untouched.
The first step is to confirm the cause. If the base is also failing, the movement will continue even with a new edge, and a wider repair is required. The sister site's page on loose and moving pavers explains how loose blocks are assessed and repaired. When the whole surface is past saving, our page on replacing old paving describes the full process, and concrete block paving covers the choice of new blocks.
For cost, kerb length, kerb type and the number of curves and details are the main factors. See factors that move the price for an overview. Kerbs set on the public side of the boundary also depend on the authorisation obtained. Send us a photo and the approximate m² – free, no-obligation quote.
Frequently asked questions
Are kerbs really necessary on a small patio?
Some form of edge restraint is always necessary for block paving, even on a small patio. It does not have to be a raised kerb: a flush edging, a soldier course bedded in concrete or a concealed concrete haunch can do the job where a visible kerb is not wanted.
What is a concrete haunch?
A haunch is a wedge of concrete placed behind, and sometimes in front of, a kerb or edging unit. It locks the kerb onto its concrete bed and stops it from tipping or sliding when the paving pushes outwards under traffic.
Which standard covers concrete kerbs?
Concrete kerbs are covered by UNE-EN 1340, with the Spanish national complement UNE 127340. Natural stone kerbs are covered by UNE-EN 1343. These standards set requirements and test methods for kerb units used in paving.
Can a wall or the house act as edge restraint?
A sound wall or foundation can restrain the paving along that side, provided it is stable and the falls lead water away from it. Where paving meets the house, a channel or gap detail is often added so water does not run against the wall.
Why are the blocks near my kerb loose?
Loose blocks along a kerb usually mean the kerb has moved, was not set on concrete, or the joints have lost their sand. Water running along the edge can also wash out the bed. The kerb and base are checked before the blocks are relaid.
Can kerbs follow a curved drive?
Yes. Curves are formed with special radius units or with standard kerbs cut into shorter sections. The aim is a smooth, continuous line without visible steps, set on the same concrete bed and haunch as straight runs.
Do I need permission to lower the kerb in front of my house?
Yes. The kerb on the public pavement belongs to the town hall, and dropping it for a vehicle crossing requires specific municipal authorisation. The procedure varies by municipality and should be confirmed with your town hall before booking the work.
What is a soldier course?
A soldier course is a row of paving blocks laid side by side along the border, usually at right angles to the edge, and bedded in concrete. It gives a neat finish and can act as edge restraint where a separate kerb is not wanted.
Should kerbs be raised or flush?
Raised kerbs separate levels, contain vehicles and guide water; flush edges allow wheels and feet to cross without a step and let water drain into adjacent planting. Many paved areas combine both, depending on what lies along each side.
Can stone kerbs be used with concrete paving?
Yes. Granite or other stone kerbs can frame concrete paving to give a more traditional look, or tie a new drive to existing stone walls. The kerbs are set the same way, on a concrete bed with a haunch, whatever the paving material.