Terrazzo, from the Italian word for terraces, is one of the earliest recycled products. Created centuries ago, the flooring surface is made by adding waste chips derived from slab marble processing to a matrix of cement.
The Venetians were the first to use terrazzo on a large scale as a decorative and functional flooring system. Venice was susceptible to flooding, so terrazzo — thanks to its durability and imperviousness — offered a creative and functional solution.
In its early years, terrazzo contained only marble stone chips. Now it also contains plastic, glass, metal, mirror and epoxy chips.
In the contemporary context, new terrazzo flooring is being installed in large commercial and institutional projects including airports, hospitals, court houses, shopping malls, and office buildings. For these types of facilities, ease of maintenance, longevity, durability, and limitless colours make terrazzo the first choice flooring solution for many architects and owners.
Although the endless variety of colours and chips inspire architects and designers, it challenges terrazzo mechanics and facility managers. The density and strength of the chip challenge the mechanic during the pouring and grinding process, since most tools and techniques were designed around stone chips. Facility managers are challenged by the difference in absorption rates and strength between various types of chips and matrix when developing specific maintenance programs for their flooring.
Since terrazzo is seamless and more than 70 per cent of its surface is stone, annual maintenance costs are generally lower than for softer surface materials. The high durability of terrazzo allows building owners to amortize the initial installation cost over decades, making it an economical long-term flooring choice. When properly installed and maintained, terrazzo can last a lifetime.
The enemies of terrazzo flooring are ammonia- and acid-based detergents, alkaline strippers and aggressive scrubbing pads. These products will not only attack the terrazzo matrix but will also deteriorate the stone chips. Before starting any maintenance program, consult the Terrazzo Tile & Marble Association of Canada (TTMAC) Hard Surface Maintenance Guide.
Wax is commonly used on terrazzo and ensures the floor remains high-lustre with the required slip coefficient (resistance). However, its removal and reapplication can reduce the life of a terrazzo floor. Wax strippers tend to have either a high alkaline or acid base. These strippers are left on the floor until they loosen and deteriorate the topical wax coating, which puts them in contact with the terrazzo. These products then need to be neutralized before they can be removed along with the old wax. If the stripper is not neutralized and removed, it will continue to deteriorate the terrazzo surface.
There is now a range of alternative, more environmentally friendly maintenance methods available. For example, when silicone and silicate-based sealers are applied to a clean terrazzo surface, they penetrate the floor and form a molecular bond with the chips and matrix. This method prevents contaminants from penetrating the surface as the sealer impregnates the terrazzo floor without compromising its natural slip coefficient (resistance).
Over time, traffic patterns will appear on both waxed and non-waxed terrazzo floors. Use diamond pads to easily remove traffic patterns and restore the floors to their original lustre. If this is done on a regular basis (about once a month), a terrazzo floor should never require full restoration.
In most cases where it’s required, restoration is possible. Many terrazzo floors have been ignored through the years because of a perceived difficulty in doing this. They may also have been damaged by multiple applications of corrosive detergents or strippers. But when considering sustainability and total long-term cost, it can be much more effective to restore an existing floor than to replace or recover it with another flooring material.
That said, the best way to ensure terrazzo lives up to its potential is through proper installation and maintenance. Consult industry guidelines before implementing a maintenance program and avoid using products known to cause terrazzo to prematurely deteriorate. With regular maintenance, full restoration should never be required.
Glen Pestrin is the CEO of York Marble, Tile and Terrazzo.