Choosing Terrazzo Flooring for Your Project
Up until the mid 1980's, Terrazzo flooring was one of the most common flooring types used because of it's strength and durability. Presently, it is still one of the most preferred flooring types for commercial buildings, healthcare facilities, and educational institutes. In this guide we explore the components of Terrazzo flooring such as how it originated, what it can be made out of, aggregate sizes, and more.
Terrazzo flooring originated in Italy and was invented by marble-workers that mixed scrap marble that they took home from their work with cement. The combination of marble and cement resulted in faux-stone floors that they then laid on their terraces.
Today, Terrazzo has a reputation for being the material for the well known Hollywood Walk of Fame, and the wall at the Gamla Stan Metro Station in Stockholm.
While Terrazzo decreased in popularity after it's craze from the 1400s-1970's, it has recently made a comeback with uses beyond flooring. Some use it as tiles, countertops, sinks, wall tiles, and more.
Composition of Terrazzo
Classic terrazzo consists of two parts.
The first part is the aggregate which is a crushed material consisting of either marble, glass, granite, or quartz. While commonly the aggregate is made up of a single material, another option is mixing two aggregates together - for example glass and marble. Depending on the manufacturer chosen, some terrazzo aggregates are made up of recycled products. Heritage Glass for example, uses 98-100% recycled glass aggregate.
The second part of terrazzo flooring is called the matrix and is the binding agent made of cementitious or polymeric binding, or a combination of the two.
As mentioned prior, the materials for terrazzo flooring are vast. While some choose to use recycled glass, marble, or other popular materials such as granite or quartz, others may be inclined to use more unusual materials such as shells or even metal shavings.
Below, we've listed a variety of the materials that can be used for Terrazzo flooring:
- Recycled Glass
- Recycled Porcelain
- Plastic Chips
- Recycled Concrete
- North American Marble
- Italian Marble
While the choice of material is usually based on aesthetic preference, some may choose recycled glass, porcelain, or concrete since they can all contribute to LEED Points.
Cement or Epoxy Terrazzo?
When specifying terrazzo flooring, the first decision you're faced with is whether to use cement or epoxy.
Cement Terrazzo encompasses sand cushion, bonded, monolithic, rustic, and polyacrylate systems. The terrazzo top is formed by the aggregate combined with a cement-based mix.
Epoxy Terrrazzo binds the aggregates with an epoxy matrix and is known for being a thinner-set system.
While both are great choices and offer high durability and low maintenance costs, they do present their own uniqueness. Below we've compared the two and offered some of the popular advantages and disadvantages of the two.
- Offers bright and complete colour customization.
- Is a thinner-set floor than cement.
- Resistance to: abrasion, stains, chemicals, high impact, and thermal-shock.
- Accommodates larger aggregate chip sizes.
- Lengthy curing time.
- Has the ability to flow nicely with any space and can be matched to a previous space.
- If moisture vapor transmission is of concern, then cement terrazzo is the better option.
- Excels with outdoor installations.
-Offers less of a colour pallette than an epoxy system, however it excels at earthy tones.
-Thicker and heavier system.
Selecting Aggregate Sizes
After selecting the colours you want for your flooring, the next step is deciding the aggregate size. Typically, aggregate sizes are between 0 to 2, however, the scale offers a range of sizes from 00 which is the smallest to 6 being the largest. As expected, the aggregate on the smaller spectrum yield cheaper costs than the aggregate that is larger. This is because the larger aggregate requires a thicker slab which increases the costs.
When it comes to terrazzo flooring, dividers are used for two purposes: form and function. Dividers are predominately used to prevent the floor from cracking, separate the different colours of terrazzo used, or to create an accent to the flooring. Ultimately they help to not only enhance the design of the flooring but also to make it structurally functional.
Precast or Poured in Place?
When considering terrazzo flooring, you have the option for installing it by a precast system or a poured in place system. Typically the installation process is selected based on funding, the time allotted for the project, and ease of installation.
Considering those standards, the precast system is typically the preferable installation method. This is because with a precast system, the tiles can be installed in a similar fashion as ceramic tiles, which makes it less time consuming to install. It is also the cheaper installation option, and offers the ability for more adaptive designs since the design can be mapped out from panel to panel.
Comparatively, the poured in place systems takes more time to install, has higher costs because of slower installation times, and cannot be as easily manipulated to make a design due to the lack of control over the aggregate.
Ultimately, when it comes to choosing terrazzo flooring, the two biggest decisions to make is the aggregate style and whether you prefer cement or epoxy. Both of these decisions will affect the final outcome of your design. So in order to ensure the best possible outcome, it's important to connect with manufacturers and use CADdetails to research and choose the products that will best fit your particular project.