Stone is ideal Paving
They're everywhere across Australia! Pebble, bluestone, river stone driveways. If there's one surface that rivals cement as the most common form of driveway (in the 'less expensive' category) it's a loose stone or cement based aggregate.
As a hard surface, stone has some significant advantages
- Durable - Long term, stone handles the weight of vehicles well
- UV proof - natural stone does not loose its colour
- Natural look - riverstone and pebbles go great next to the garden
- Permeable - Unlike concrete hard surfaces
Loose Stones needed Binding!
One of the earliest forms of civil infrastructure was of course a highly compacted loose stone or as its now know a 'road base'. The method of compaction was pioneered in 1820 by John McAdam and the process was referred to as Macadamising roads or Macadam roads.
As technology evolved, the binding of loose stone roads became advantageous for longevity. Early gravel binding was done using asphalt or black coal tar. Unsurprisingly coal tar was the byproduct of burning town gas, which was the primary form of energy at the time. Indeed, linguistically the word 'tar-mac' is a portmandeau of 'Coal Tar' and 'Macadam' or compacted stone roads'
CEMENT based aggregate
Without doubt, cement is still the most common form of adhesive or binding agent used to secure stones in paving. Cost and durability are the main factors that make cement based stone paving the most common choice for exposed aggregate paving across Australia.
When relatively new, a freshly paved stone surface looks fantastic and can last for decades. However, when stone starts to come loose, it becomes an eye-saw, another cost and a constant reminder of something to add to the 'must do list'
Unsurprisingly smaller, rounded stones like pebbles suffer the worst of erosion. They are decorative and soft underfoot due to their small size and round shape. Whilst common on residential pathways, pebble paving is obviously ideal for use around pools.
However Pools are notorious places for puddles to form and friction (high foot traffic) to occur. The result, more and more loose pebble that collects in drains, scratches interior timber floors and eventually leads to cracking.
Pebbles - Used for pools as the are small and rounded to be soft on the feet
When Paving shows its age
Of course as time goes on, the forces of nature do their best to destroy these durable surfaces.
Not taking into account issues like ground movement, tree roots or cracks from falling hard objects, the three main forces that drive erosion on bound stone paving are Water, Friction and UV damage.
This gets progressively worse the more the stone comes loose and cement is exposed to more and more of the damaging UV rays of the Sun.
How long before I need to resurface
Whilst concrete based aggregate driveways will last over 10 years, a more pertinent point is how long before you see stone coming loose? How will it look in 5 years?
There are many factors - including the quality of the cement, how 'rounded' is the aggregate. However the main ones again are how common do puddles form, how much sun they are exposed to and what vehicular loads are they subject to?
Consider this - a cement based driveway (with quality aggregate) can often cost the same as using a resin bound aggregate (depending on driveway size & location)
Cement based $80-150/sqm
Resin BASED $120-180/SQM
At these comparable rates - the decision to go with a resin bound stone that will far outlast cement based options. Indeed because StoneSet has a porous structure, it avoids the vast majority of the erosion cycle. This one of the greatest features of a StoneSet driveway - it will hold that 'new look' much longer than other aggregate driveways. This is how StoneSet offers the 10 year 'no loose stone' guarantee.
Stoneset. do it once - do it right!
Unlike cement based aggregates, StoneSet is made of multiple layers of resin bound 6mm stone.
Water doesn't collect on the surface, draining freely - meaning no puddles to aid erosion or mould such as the common black spot algae.
Underneath the surface the stone is bound at multiple points by a very strong, waterproof polyurethane binder. Even for the 6mm stone on the very top layer (shown below) the resin binds at multiple points, effective 'locking' each stone in its place in a very strong matrix.
These are the two reasons why resin bound stone paving like StoneSet outlasts the common cement based aggregate surfaces, by avoiding the erosion cycle;
- Porous - No puddles can form, avoiding erosion via friction
- Resin Bound - No UV can penetrate the Polyurethane binding agent
Furthermore - Resurfacing once with a 16mm layer of StoneSet over 20 years is far more environmentally friendly than having to resurface twice in that period using cement, given the latter has significant carbon emissions;
Cement manufacturing is highly energy- and emissions-intensive because of the extreme heat required to produce it. Producing a ton of cement requires 4.7 million BTU of energy, equivalent to about 400 pounds of coal, and generates nearly a ton of CO2. Given its high emissions and critical importance to society, cement is an obvious place to look to reduce greenhouse gas emissions.
not simply porous Paving
For many Australians that enquire about the product here at StoneSet every day, resin bound stone paving is still remains somewhat of a premium, expensive and somewhat of a luxury.
Admittedly across Australia, the product is best known for having one of the highest porosity rates amongst other forms of permeable hard surfaces.
Indeed many residential customers are most familiar with the product as a result of council regulations for Tree Protection Zones and hard / soft landscaping ratios for development applications.
So its no surprise then StoneSet is still viewed as one of those niche Architects products; Primarily the domain of heritage listed locations or very high end residential properties.. typically "not relevant" for most residential homeowners.