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Edging & Kerb Calculator

Estimate stones, ballast, and cement for perfect boundaries.

Material Takeoff

Haunching Tip: Always 'haunch' the back of the kerb at a 45-degree angle. This concrete 'buttress' prevents the kerb from tilting backwards when soil or paving is pushed against it.

Kerb Appeal: Defining Your Landscape

Boundaries with Purpose

In UK landscaping, edging kerbs serve two roles: they provide a clean visual finish and, more importantly, they act as a structural restraint. Without solid edging, driveway blocks or paving slabs will eventually drift outwards.

Our **edging kerb calculator** helps you calculate the precise number of stones and the exact amount of ballast and cement needed to secure them for decades.

Kerb Profiles

Flat Top (Garden)50mm x 150mm
Bullnose (Driveway)50mm x 200mm
Path Edging (Round Top)38mm x 150mm

The Secret to Straight Lines

The key to professional-looking kerbs is a **string line**. Drive two pins into the ground and stretch a line tightly between them at the exact finished height of your kerb.

Always set the concrete bed first, lay the kerb, tap it down to the string line with a rubber mallet, and *then* add the haunching behind it. If you try to add the haunching later, it won't bond effectively to the bed.

Earth-Moist Mix

Professional groundworkers use a 'dry' mix for kerbs. This means adding just enough water so the concrete holds its shape when squeezed. This allows the kerb to sit on top of the concrete without sinking.

Expansion Gaps

For very long runs (over 20m), it is wise to leave a small 2-3mm gap between every 5th or 6th kerb stone to allow for thermal expansion during hot UK summers.

Pro Tip: Front Haunching

If the front of the kerb will be hidden by soil or turf, add a small haunch to the front as well. This creates a 'u-shaped' concrete channel that makes the kerb virtually impossible to dislodge.

Edging & Kerb FAQ

Technical Disclaimer

Concrete requirements are based on standard haunching profiles. Uneven ground or deep trenching will increase the amount of ballast and cement needed. Always order 10% extra for waste.