Photo 1: Natural linoleum continues to maintain its popularity as a “green” flooring option, and more installers are seeking out the training to learn to properly install it.


Photo 2: Crumb rubber flooring contains recycled rubber and is manufactured when a 3,000 lb. cylindrical mold of rubber is sheared into a thin layer to become sheet rubber flooring. (Photo courtesy of Ultimate Systems LTD)

One of the more overused words in our lexicon these days is “green,” and I don’t mean the color.  With the growth of environmental awareness in general, the construction industry is bustling with projects that are using products and practices that are environmentally responsible.  The terms “sustainable, eco friendly, Floor Score certified,  LEED,” and a host of other terms are being applied to all kinds of building projects including floor coverings. There also are a growing number of construction and installation practices that are required as part of these projects. I covered this subject almost two years ago in my column “Green” Flooring - What Does It Mean To Me? (FCI May 2008), so here is some new information that may be helpful.

Mention “green” resilient flooring and the products I think of right away are cork, natural linoleum and recycled rubber.  However, the category has grown to include vinyl products with recycled content, “PVC free and “non –vinyl” products made from new types of polymers like olefin and “bio based” products made from vegetable-based polymers.  Here are a few points regarding installation of some of these products.

Cork is a 100-year-old commercial and residential flooring product that I have covered here in FCI several times. It starts as the bark of a type of oak tree that is stripped and grows back every nine years or so.  For this reason it is considered a “rapidly renewable resource.”  It is also considered “recycled” because the waste from the primary use of cork (wine bottle stoppers) is turned into a variety of products including floor tile.   As far as installation, the cork floor tile industry has moved away from the trowel applied adhesive method that saw some use several years ago.  There were just too many problems making that method work, so the industry is once again using water-based contact adhesive, a method experienced cork installers here and in Europe unanimously prefer because it firmly holds the tile in place with no curled edges, allows the installer to work on top of the newly installed floor and allows foot traffic on the floor almost immediately.   The tile can be coated a day ahead of time and large areas of the substrate can be coated at one time.

I covered natural linoleum installation in a recent column, so I won’t repeat myself here.  It’s a beautiful and durable material that is different to install than a lot of other resilient flooring materials.  But when it’s done right, there are a lot of beautiful possibilities.

Recycled rubber floors, officially known as “Bonded Rubber Crumb Floor Coverings,” start as the remains of old tires mixed with other rubber, some recycled and some new, and even cork in some cases.  Although it is known as a floor that is used in gyms and other sports applications, it has really taken off for use in all kinds of other areas, mostly in commercial space. There are “interlocking” tiles that are loose laid but most of the product, either roll goods or tile, is glued down. When installing crumb rubber, pay attention to adhesive recommendations – sometimes it a one-part urethane product and sometimes a two-part epoxy, depending on the use. Either way, it’s a wet set adhesive so floor prep and staging are important to be sure the material is set into the adhesive before too much time goes by.

Rolling the floor after installing is also a key to make sure there is full contact with the adhesive.  Just like cork, rubber must be acclimated on the job site for at least two days before installing. Tiles need to be laid flat and rolls should be unrolled and allowed to relax for 24 hours before installing.  Most manufacturers say it’s not necessary to trim the edges of recycled rubber roll goods because it’s done at the factory. However, have a look to be sure the edges are clean and straight and trim if necessary to get it that way.  Recycled rubber continues to grow in popularity, and rightfully so.  I have worked with this material more and more in the past few years and it has become one of my favorite floors because of its use of recycled material, its softness under foot, ease of maintenance and durability, not to mention some beautiful colors that make it a great looking floor covering.

Some of the other so-called “green” resilient flooring products are installed in a way that is very similar to other products but then again some are quite different.  A lot of them are “wet set” adhesives, so be sure to figure the right amount of time to install these materials. 

Finishing and maintenance of these products have evolved in recent years, and more and more installers are expected to do initial maintenance.  Cork, recycled rubber, linoleum and even conventional vinyl and VCT products are increasingly being coated with a new generation of flexible water-based urethane coatings.  These long-lasting finishes eliminate the need for floor finishes, waxes, and/or buffing so they are being specified as a way of reducing maintenance costs and chemical use.  Because these coatings are usually applied to new floors soon after they are installed, the installer is sometimes asked to do this work.  This is another new area for installers to learn.  Having the skills to do initial maintenance, especially applying urethane coatings, will generate new work and income.   Getting trained on these products is a great idea.  Many of them are quite easy to work with, so it is not too hard for an installer to learn the craft.

One of the aspects of green buildings today that is changing rapidly has more to do with work practices than it does with the actual green products themselves. Some of the new requirements present challenges for installers.



Photo 3: A properly prepared moisture test site. The ASTM F 1869 calcium chloride test is in the center and the F 2170 relative humidity test is to the left of the calcium chloride kit.

“Indoor Air Quality” is being monitored more closely than ever, so care needs to be taken with floor preparation and patching or leveling compounds that generate dust.  Dust control is being mandated on many projects.  For this reason and other reasons, the building Heating/Ventilation/Air Conditioning (HVAC) systems are often not activated until construction has been completed so duct work is not contaminated by dust and other airborne contaminants.  This presents challenges for floor coverings and concrete moisture testing, not to mention a lot of other building materials that require temperatures to be in the 50o – 80o temperature range.  As a result of these requirements, temporary climate control systems are being used and some of them are very good.  However, they need to be left on around the clock so that materials stay dimensionally stable and adhesives and coatings, cure correctly.  I’ve seen several failures of flooring materials that were installed at extremes of temperature.  Be sure the construction team knows the temperature requirements early on so they can have the job site ready for you. Stick to your guns and demand that the site be ready.  The products and adhesive don’t act the same way when used in very warm or very cold conditions so there is an increased chance of flooring failure if temperature guidelines are not followed.

The other aspect of indoor air quality has to do with “low emitting” or “low VOC” products. VOC means Volatile Organic Compounds and this requirement mostly has to do with adhesives, seam sealers and finishes.  Be prepared to be asked about VOC information and MSDS (Material Safety Data Sheet) details.  The manufacturer will have this information available and in many cases it is on the container. Take care to ventilate the area so that odors are kept to a minimum.  It is also important that certain types of adhesives be handled properly because they can be a hazard.  Solvent-based contact adhesives and many types of resilient seam sealers have a strong odor, are flammable and the fumes are hazardous to breathe.  If you have to use these products, ventilation is very important and it is also critical to keep the containers open only as long as necessary so the fumes are kept to the absolute minimum.

Finally, concrete moisture issues are increasingly being looked at with regard to how “green” a building is.  We have talked at length about how excessive moisture vapor emissions affect adhesives but the issue of mold growth as a result of moisture is a concern because of indoor air quality.  In addition, the extra humidity in the air that comes from vapor emissions can add to energy use because of the added dehumidification load on the HVAC system.  As such, moisture testing is more important than ever so that any potential moisture problems can be addressed before the floor is installed.  If a moisture mitigation system is required, a low emitting product will need to be specified.  Not all products will meet these requirements so it may take a little research to get the right moisture mitigation system to meet the needs of a “green” project.

As “sustainable” design continues to grow, floor covering manufacturers are meeting the needs of the design community with new products.  Installers and floor covering dealers/contractors need to be aware of what’s out there so they can properly install and in many cases maintain the increasing number of products being used on these projects while also being aware of indoor air quality issues and work practices.  It is a bit of an adjustment from “the way it’s always been done,” but you will be an important resource to the design and construction community and will have a lot of work if you can “go green.”