Bonded or Bound (Scroll down for a gallery of some our contracts.) Our industry continues to confuse by using two very similar terms to describe two quite different types of installation. For clarity the two terms are defined here.
Bonded Aggregate Sample
Bonded Aggregate
Bonded Aggregate describes the technique of bonding aggregate to an existing surface.
Adhesive is spread on the surface. Whilst it is still liquid a layer of aggregate is spread over it. When the adhesive has set, any excess aggregate is swept off to leave a layer of aggregate BONDED to the surface. We sometimes describe the effect as producing a "stuck down gravel path."
This system is typically 4mm to 6mm thick and is textured. The technique is sometimes referred to as "Scatter Coating" or "Coat and Scatter".
Bonded Aggregate is a durable, low maintenance surface ideal for use in almost any type of landscaping project. Systems can also be produced complying with Dept of Transport clause 924 for high friction surface dressing.
Detail of a compass design on a highway roundabout
Bound Aggregate Sample
Bound Aggregate
Aggregate is pre mixed with a non yellowing clear resin before it is applied. The mixed material is then applied by trowel. The thickness can be adjusted to suit various site conditions and service requirements.
When installed on a robust sub base the system can be as little as 12mm thick.
We now have the ability to install on compacted fill at only 30mm to provide sufficient mechanical strength for use by vehicular traffic.
Because it is trowel applied, the system is relatively smooth. This technique is sometimes referred to as "Hand trowelled". Using natural aggregates bound with non yellowing aliphatic resin we can produce a durable, very high quality, low maintenance surface for use in almost any type of landscaping project. Bound Aggregate can be installed onto compacted sub base and the porous type makes an excellent surfacing for tree planters.
The system is ideal for pathways where a smooth, less textured surface is required. With a choice of aggregates from flint and granite to different shades of crushed glass the designs are limited only by your imagination.
BOUND AGGREGATE COMPLIES WITH SUDS In recognition of the need to more effectively manage surface water run-off, the Environment Agency introduced a Sustainable Urban Drainage approach (SUDS), to water management