Question

Is recycled rubber flooring a green and healthy choice? We're considering it for a basement living space.

Asked by Harvey Buford
Ashaway, RI

Hard to find a good answer. Recycled rubber seems very green. But are there harmful outgassing or just nuisance smells? Do these issues go away with time? Are some manufacturers' products safe and others not? Whose are safe? Who certifies this? Will an air cleaner get rid of the rubber smell? Maybe I am on the wrong track. What flooring materials do you recommend for a basement?

Answer

Cynthia Phakos

Answered by Cynthia Phakos

Los Angeles, CA

Koffka Phakos Design

February 23, 2012

This is a great question as it presents the challenges of evaluating products with recycled content.

To briefly address some of your questions:

  • Recycled rubber flooring is very green as it diverts used products from the landfill, and is a durable, renewable material. 
  • There can be off-gassing of VOCs which could be harmful if one has sensitivities. These odors will dissipate over time into the atmosphere.
  • Manufacturers’ products vary in their environmental and health impacts. 
  • FloorScore is a certification program that tests resilient flooring products, like rubber flooring, for Indoor Air Quality. FloorScore certified products work well for a basement with the proper installation

Rubber recycling

Over a billion tires a year are produced world wide annually, with the US scrapping 290 million tires annually (Wikipedia). As they don’t break down over time, recycling them is very worthwhile.

The primary uses for the recycled rubber are road/site work, burning for fuel, and paving/flooring products.

The EPA has looked closely into the use of recycled rubber from tires as an exterior paving material for exterior school recreation areas.

  • In 2010, their findings were that the material did not present any potential environmental or health concerns.
  • At that time, there were already 45,000 sites using the material according to AmericanRecycler.com (February 2010).
  • The EPA is now investigating its application in other areas, which makes your question very timely.

Rubber flooring content

Tires today are made up of polyester cords and steel wires encased in a flexible material made from synthetic and natural rubber along with a small percentage of chemical compounds.

  • In recycling, the tire is first shredded or chopped into small pieces.
  • The steel and polyester fibers are removed, leaving a crumbed, shredded rubber.

Depending on the manufacturer and desired aesthetics, a very high percentage of the flooring can be made up of this recycled black tire material.

  • Colored rubber granules is added for color, and so the blacker the end-product the higher the percentage of recycled content.
  • Greenpeace recommends (here) avoiding rubber flooring which contains chlorine-based ingredients and reports that EPDM is recommended by the Danish EPA.
  • A binder, typically a urethane, is added to the recycled and synthetic rubber to form the flooring or paving material. In some cases the binder can make up to 10% of the material content.

Indoor air quality

Off-gassing is an important consideration in the selection of flooring, especially in a place where there is little ventilation, as the basement. In evaluating the off-gassing of the finished material, all of the components above need to be considered.

FloorScore is a certification system which was developed by the Resilient Floor Covering Institute (RFCI) with Scientific Certification Systems (SCS), an organization which certifies building products for compliance with LEED and other environmental programs.

  • A FloorScore certified product has been tested for compliance with the volatile organic compound (VOC) emissions criteria of the California Section 01350 standard, the most stringent US standard.
  • The SCS site lists recycled rubber flooring products with FloorScore certification.
  • A product that I found is Dinoflex's Evolution, a commercial flooring that is either glue down or a click together tile (a thicker material). I have seen this product at tradeshows and was very impressed with its appearance as well.

Basement installation

Recycled rubber flooring is a good solution for a basement floor, as it

  • acts as an insulator for the cold concrete floor,
  • is a very good sound absorber, and
  • has a longer life (20 years) than vinyl or carpet products.

As there are sometimes water issues with a basement, recycled rubber is porous and so has the ability to dry out. With that said, I would still recommend using a low or 0 VOC concrete sealer before installing the rubber flooring.

As you are installing this in the basement you might consider letting the material air out beforehand, which will minimize any miscellaneous odors.

  • You could request that the installers do that in the warehouse for 48 to 72 hours prior to installation.
  • But it is more likely to be done if you do it.

Glue down vs click together tiles

Click together tiles (which look like puzzle pieces) can be installed without any adhesives which would make the tile at the end of life 100% recyclable by the manufacturer, closing the recycling loop, while also avoiding any off-gassing from the adhesive which could potentially be a bigger issue then the odors of the rubber flooring.

  • From my own experience, I have installed a thin sheet recycled rubber flooring, glue down on concrete slab and the end result had a harder surface than I had expected.
  • If it is a soft floor material you desire, for kids to play on, I would recommend selecting the click together tiles.
  • It will be more expensive but you could install it yourself without adhesives.

If you do choose a glue down product, a low to 0 VOC adhesive is highly recommended.

Tagged In: basement flooring, basement remodeling

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