Recycled Rubber and EPDM

There is no broader term in the flooring industry than rubber.  Recycled rubber or vulcanized rubber, rolls or tiles, square edge or interlocking, the list goes on and on without even touching on the different thicknesses and colors.  Perhaps one of the least known aspects of recycled rubber is the relationship between recycled content and EPDM added for coloring.  To gain a foothold into the world of rubber, understanding the breakdown of recycled rubber is key.

A standard rubber installation

Recycled rubber is the most commonplace rubber in the industry.  It is remnants of ground and chewed up car tires and previous rubber flooring.  Impurities such as dirt and oil are washed with sulfur and other chemicals.  Once the material has been cleaned these granules are then bonded together, usually with a polyurethane binder, to form into a cylinder, also called a bun.  The bun is then shaved into a single layer of recycled rubber flooring at the desired thickness.

This recycled rubber is both versatile and inexpensive, able to fulfill a multitude of purposes.  The least expensive is underlayments, providing a softer, more shock absorbent surface that other floors can be installed upon.  Rubber also has higher sound absorption rating than most other underlayments on the market. Underlayment is typically made up of entirely recycled rubber with no EPDM chips added.

The black portion is the standard recycled rubber and the blue is the added EPDM chips.

Moving up in quality, there is the traditional recycled rubber that is found in many weightlifting facilities, such as an 8mm rolled rubber.  This rubber often has EPDM chips, colored rubber that has been mixed into the recycled rubber during the production process.  These chips can be in a rainbow of colors and provide unique visuals.  EPDM is a virgin rubber and is added to the recycled content to provide untainted coloring in the final product.  Typically, the more EPDM in a product, the better the quality and the better the visual.

Example of a Dual Density System

Dual density systems are used to create a system where certain color and height requirements are wanted at the most efficient price point. The bottom first layer consists of only recycled rubber, either as an underlayment or a higher density rubber depending on the performance needs of the room.  The top layer of the system can be a different density and have added EPDM color chips to add to the design.  This 2 part system can be chemically bonded at the factory, or delivered to the job site in 2 different layers that are then installed in the field to create a dual durometer system with thicknesses up to 1”.