Knowing the main technical properties of the materials you intend to use will help you make an educated decision. However, once you dive into technical properties and their rating systems, it can all become quite overwhelming.
Here is a quick overview of the top 5 characteristics to understand and determine what material to use, where and why.
Abrasion resistance refers to the ability of a material to resist surface wear. Within the industry, several different measures for abrasion resistance may be referenced. Mohs is perhaps the most common, but you may also see PEI ratings, ASTM or ISO ratings for porcelain or ceramic tile.
Typically, the Mohs scale is applied to minerals, as they are the only geologically pure materials found in nature and are very consistent in their results. Unlike pure minerals, natural stone consists of several different types of minerals and will react less predictably than a pure mineral. To accommodate for this range of ratings, it is common practice to adhere to a broader scale rating of a material’s performance as High (man-made quartz, quartzite and granite, scoring a 7 or higher on the Mohs scale), Medium (certain marble and limestone, scoring between 3.5 and 6.5) and Low Abrasion Resistance (e.g. marble and limestone, between 1 and 3 on the Mohs scale).
Absorption, as it relates to natural stone, refers to the relative porosity of the material. Materials with minimal and moderate absorbent rating are resistant to staining due to low porosity, but not impervious. Materials with highly absorbent rating are prone to staining. Always seal any natural stone material prior to grouting by applying sealant / impregnator until water beads up on the surface (this process will need to be repeated periodically to extend the longevity of the stone). To reduce the appearance of stains, always wipe up spills immediately.
By its very nature, porcelain, ceramic, glass tile and man-made quartz are not considered absorbent materials and are rated as minimally absorbent. While there are tests that measure both water absorption (ISO 10545-3) and stain resistance (ISO 10545-14) these tests are specific to the porcelain tile industry.
- Acid sensitivity
Materials that contain calcium or magnesium carbonate (marble, limestone, travertine and onyx) will react to acidic foods (i.e. lemons or tomatoes) and acidic liquids (i.e. some cleaners or acid rain).
This reaction will result in a dulling of surface sheen and a change in texture – otherwise referred to as “acid etching”. Generally, acid etching is less visible on lighter materials and honed surfaces. If acid etching is a concern, select a minimally sensitive material, such as granite and quartzite.
Freeze-thaw cycles occur in exterior applications when water seeps into the surface of a material and then freezes. The process of expansion causes the material to crack or spall; repeat freeze-thaw cycles will widen the void until the material breaks.
This characteristic – in combination with absorbent rating, abrasion resistance, color fastness and tensile strength – determines whether a material is suitable for all external applications (these materials will patina), suitable for vertical external applications only (although frost resistant, these materials will stain and therefore are not suitable for exterior paving applications) or not suitable for external use at all.
Traffic ratings refer to a material’s ability to withstand the anticipated volume of foot-traffic through a space. Typically, the industry adheres to a rating scale of:
- Heavy Commercial Traffic
- Medium Commercial Traffic (shopping malls, airports etc)
- Low Commercial Traffic (hotels, restaurants, bars)
- Residential Traffic
If you are have any question or require further assistance, speak to us. We are always happy to provide more in-depth information and assistance to make your next project successful.