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We’ve reviewed these procedures for general consistency with federal standards for rehabilitating historic buildings and provide them only as a reference. Specifications should only be applied under the guidance of a qualified preservation professional who can assess the applicability of a procedure to a particular building, project or location. References to products and suppliers serve as general guidelines and do not constitute a federal endorsement nor a determination that a product or method is the best alternative or compliant with current environmental regulations and safety standards.
This standard includes general information on the characteristics and common uses of terrazzo and identifies typical problems associated with the material.
Introduction
Terrazzo was created in Europe several hundred years ago by the Venetians who experimented with reusing marble chips by setting them in concrete. Further experiments with polishing resulted in a smooth surface for walking. After marble was brought to the U.S., marble dust was added to make different colors. Wood strips were used to separate sections when casting. The wood strips were then replace with another material.
Characteristics of Terrazzo:
- Terrazzo has been described as a decorative form of concrete. Random sized marble chips are mixed in a binder, troweled, ground and polished.
- Good terrazzo has a smooth surface that is a mixture of 70% or more coarse marble aggregate and 30% or less Portland cement matrix.
- Terrazzo combines the durability of marble with the strength and economy of concrete.
- Ease of maintenance - is one of the principal reasons why terrazzo is found in so many buildings where traffic is heavy.
Types of Terrazzo:
The biggest difference between types of terrazzo is the type of binder that is used. The binder, which is either a Portland cement or resinous base, serves to hold the aggregate in place. Different binders require different sealing procedures.
- Terrazzo with a Portland cement binder
- Terrazzo with a polyacrylic-modified Portland cement and acrylic additive binder
- Terrazzo with a epoxy or polyester resin binder (a.k.a. resinous thin-set system)
Typical Uses
Typical historical and 20th century uses for terrazzo:
- As a flooring material in public buildings.
Typical uses for terrazzo in the 20th century:
- As a flooring material in places like airports, convention centers and shopping malls.
Problems and Deterioration
- Has a reputation for being maintenance-free
- Sensitive to harsh cleaners
- Sensitive to all-purpose cleaners and soaps containing water- solubles
- Avoid sweeping compounds containing oil as they may permanently discolor the floor
- Portland cement systems must be sealed with a penetrating solvent-type sealer after final polishing to protect the porous cement binder
- Resinous systems can be sealed with a non-penetrating or surface type sealer since the matrix in this system creates a non-porous surface
For additional information on terrazzo, see the following procedures:
- Routine Preventive Maintenance Guidelines for Terrazzo
- Removing Ink Stains from Terrazzo
- Stripping and Cleaning Dirty or Discolored Terrazzo Floors
- Patching Minor Chips and Cracks in Terrazzo With Cement Grout
- Installing a New Bonded Terrazzo Floor to Match Historic Terrazzo
- Epoxy Patching Cracks in Terrazzo Floors
- Removing Lubricating Oil Stains from Terrazzo Floors
- Removing Tobacco Stains from Terrazzo Floors
- Removing Coffee Stains from Terrazzo Floor
- Removing Iodine Stains from Terrazzo Floors