Getting It Naturally Right - Benefits of Natural Stone
By Phil Beer, Operations Director, Natural Paving USA
Because natural stone, such as the charcoal colored Classicstone used at this commercial site, is naturally sourced, two projects that use the same paver type and color will never look exactly the same. When ordering natural stone pavers for a project, plan ahead for future expansions and order a decent amount of overage: in a few years, the stone available for an expansion could look completely different than the original installation.
When tested for ASTM standards of compression strength, absorption rate, and slip resistance, the Classicstone range produced by Natural Paving USA (shown here in 'Harvest'), exceeds the industry standards. The pavers can withstand 15,260 psi, nearly double the industry standard of 8,000 psi for concrete pavers. The absorption rate measures in at 1.2 percent, compared to the industry standard of 5 percent or less. And the slip resistance is 1.46 in dry conditions and 0.94 in wet - the higher the number, the less likely it is for someone to slip. A measurement of 0.60 is considered standard.
There's nothing quite like natural stone. Each piece has a unique blend of color and tones with no added pigments, so no two flags are the same. Natural stone becomes an evolving element within a project, aging over time to become a living part of a property's aesthetic. With natural stone, landscape contractors can create a completely custom, high-end driveway or garden landscape for their clients that will be the envy of the neighbors. Mark Wall, Chief Executive Officer at Natural Paving Products USA, details the benefits of using natural stone and best practices for selecting and installing it.
As well as being aesthetically pleasing, natural stone has considerable benefits for the end user in terms of its durability and longevity. It retains its look over time, getting better with age, unlike products manufactured from composite aggregate mixes that may become exposed after a few years of trafficking. Natural stone paving is also frost-resistant. Ease of maintenance is another advantage of natural stone comparable to other hardscape alternatives.
Selecting Your Natural Stone
To ensure you get the most durable natural stone, it is important to choose a high quality natural stone manufacturer. Find one that offers products that have been ASTM tested in the USA.
The ASTM testing covers areas such as water absorbency, flexural strength and frost resistance. Select a manufacturer whose products have been tested to show the various properties of each stone and how the stone is likely to behave and react under different circumstances. Recent tests include PSI (Compressive Strength ASTM C140-15), Absorption rate (ASTM C140-15) and Coefficient of Friction rate (ASTM C140-15).
During a series of tests on the previously mentioned manufacturer's 1" Classicstone(TM) range, the average PSI, compression strength is 15,260. (The industry standard for concrete pavers is 8,000 PSI.) The absorption rate is very low for a paver at 1.2%, particularly apt for colder climates. (The standard for concrete pavers is 5% absorption or less.) The slip resistance, measured by the coefficient of friction, showed a scale of 1.46 in dry conditions and 0.94 in wet. (Anything above 0.60 is considered sufficient - the higher the number, the greater the force to move an object, and the less likely it is for someone to slip.)
An increasingly important consideration for end-users when choosing building materials is a product's sustainability. For many, natural stone is considered the most sustainable building material on the market. This is because there is a vast resource of natural stone on earth and although its regeneration is not as readily visible as the regeneration of trees, it is a continuous process with natural stone having an enduring life cycle. Being natural, the stone products are recyclable and can be used as reclaimed paving or for aggregates. Alongside sustainability, a crucial question for many modern end-users is whether their product has been sourced ethically. A lot of sandstone used in hardscapes is imported from Indian quarries, some of which have been linked to corruption and child labor. As a member of the Ethical Trading Initiative (ETI), this company is demonstrating to the industry how natural stone mining can be conducted successfully and ethically. It has invested a significant amount of time, money and resources, working hard to ensure that all workers at home and abroad enjoy the best possible living and working conditions.
Installing natural stone is as easy as installing concrete pavers, and can be done using sand-set, mortar-set, or concrete overlay methods. Some manufacturers will provide natural stone in pre-cut squares with patterns, eliminating the need to solve the puzzle of how to put the pavers together.
Beyond paving for patios, natural stone is available in bullnose finish as well as chiseled, so it can be used for steps, retaining wall caps, or pool coping. Additionally, the pavers can be recycled and used as reclaimed paving or aggregates.
Installing Natural Stone
Many contractors are already aware of the benefits of natural stone, but may be reluctant to use the product on grounds of the perceived difficulty in installing it. This misconception that natural stone is somehow trickier to install than other hardscape products could not be further from the truth - the installation of natural stone is similar to laying concrete products and does not require any new skills.
Contractors will find that installing natural stone products is easier than they think and does not require a stonemason, or any specialist training. Many suppliers will also include easy-to-follow patterns and laying guides as standard. The installation technique chosen for a project should be determined based on each individual job site and region. The three most popular installation methods are sand set, mortar set and concrete overlay.
For added convenience look out for calibrated stone that comes in pre-cut project packs in squares and rectangles with consistent thickness. This will keep cutting to a minimum and save time, as unlike irregular shaped native stone they do not have to be cut into shape on site.
Given such high performance in terms of quality and durability, natural stone is a safe investment that could increase property value and decrease maintenance costs. Offering beauty, longevity, sustainability and high performance credentials, it is a natural choice that can really add wow factor to a property's aesthetics.
As seen in LC/DBM magazine, January 2018.Click here to go back to the latest news.