Staining of Sheet Vinyl Flooring

Discoloration problems with resilient flooring are common and can develop from above the product surface, below the product surface or the product itself. Both bottom up and surface down problems are routine and most noticeable on lighter colored material. Due to construction characteristics a rotogravure product will stain easier from the back than an inlaid product that will almost always discolor face down. Few discoloration problems are due to a manufacturing defect. Most discoloration problems are either installation or consumer related and the wise installer will be aware of those that he can be held responsible for and take steps to prevent them.  Likewise the dealer needs to be aware of potential problems so that the installation is properly inspected and bid and the consumer is warned of potential problems.

Yellowing

• A high percentage of yellowing, possibly as much as 95% is external.

Manufacturing

• Retardant yellowing can occur in 2 -3 months in low areas.

Sun spot yellow (heat degradation)

• Looks like big freckles in a solid brown or purple.
• Found near heat registers and sliding glass doors.

Transfer From the Back

• Inks with dye will show through on face, pigments will not.
• Mildew and mould does not have to be in both the embossed and raised section.
• Has never seen a topical mildew problem on urethane.
• Asphalt tracking - It is the sealer or coating that causes the yellowing. An asphalt drive without sealer will not cause yellowing. It makes no difference what type of sealer is used. When a floor is washed it is spread and the whole floor can become yellow.
• Sealed driveways, decks, oil and grease, lawn care products, pattern, and color shape. Geometrical shape is external.
• Sun tan lotions such as Paba and Oxy with sun blocker will discolor
• Black Light
• Long wave is preferred to short wave but either will work.
• Tracking type asphalt tracking glows
• Retardant inks glow as blue white in lines
• Stains of petroleum base will glow
• Heat degradation will glow
• BHT

Adhesive - Non-recommended: A manufacturer recommends certain adhesives that have been formulated to be compatible with their floor. The recommended adhesive may cost a bit more in the beginning as often contains more expensive clays, processing oils and anti-oxidants. An improperly selected adhesive may be less expensive, but it may also contain oils that are dark in color, or have a syrup-like consistency.  The result of this adhesive is vapors from the anti-oxidant and processing oil migrating up into the material through the backing where they interact with the ultra-violet light and result in a yellow discoloration.

Adhesive - Old Latex Adhesive Residue: As with the improper adhesive, the processing oils and anti-oxidants in the old adhesive may not be compatible. If old adhesive residue is not completely removed from the old floor it may cause yellowing.  This will be more of a problem with flex floors and homogeneous vinyl’s than it will be with a felt backed product which acts as a barrier.  80 to 100 percent removal will be required depending upon the product.

Adhesive - Asphaltic Cutback Adhesive Residue.  If this adhesive residue is present after tile removal and not completely removed or covered with a suitable underlayment, it will often cause a yellow discoloration on the new floor. It is important to understand that this type of adhesive and tile may contain asbestos.

Asphalt Saturated Lining Felt: This felt will stain resilient flooring and is not recommended as an underlayment for resilient floor covering.  The lining felt must be removed or covered with a suitable underlayment.  Lining felt may contain asbestos.

Construction Adhesive: Using this adhesive to adhere underlayment to subfloor often results in a yellow discoloration.  These adhesives contain strong anti-oxidant.  It gets into the vinyl and reacts.  Typically it telegraphs at subfloor lines, nail holes or other areas where gas can penetrate.  This anti-oxidant discoloration is not correctable.

Gypsum-Based Patching Compounds and Underlayments. These products routinely contain carbon or starch. This food source for fungus spores once mixed with moisture will create an ideal environment for its growth.  Fungus / mildew growth leads to discoloration’s of many colors i.e. pastel blue, pink, yellow, orange.  The best prevention is moisture testing to assure that you are working in a dry area and the use of a Portland cement based patching compound when installing below grade or over concrete.  A gypsum-based patch for wood and dry suspended concrete is suitable, only if it is free of any food source for fungi.

Petroleum Based Products - Wood Stain, Paint, Paint Thinner, Kerosene, Heating Oil, and Oil-Based Stain: These products can often be hard to detect.  If spilled or dripped, they will penetrate a subfloor and if not completely removed before installation, they will often result in yellowing of a resilient floor.

Pink Synthetic Polyurethane Patching Material: This pink colored material, was most commonly used in the middle 80’s, it is used to fill knots and other voids in wood panel underlayment. While the material is pink, the discoloration to the floor will be yellow.  The discoloration will duplicate the shape of the patch in the underlayment.  Plywood underlayment that is recommended for use with resilient floor coverings and carry the APA (American Plywood Association mark use a safe patching material.  It should be noted that this problem was most common in mid-1980.

Reconstituted Wood: Oriental Strand Board (OSB) and Waferboard.  Some of these boards contain dark colored wood chips and strands that can discolor a vinyl floor covering.  As with other Underlayments, it is important that it be purchased from a reliable source that will guarantee the product and stand behind the problem should it occur.

Resin Coated Nails: These framing and sheathing sinkers are not designed for floor covering. While not all resin coated nails will create a problem, many will and unless you can be assured that those you are using will not, it is best to stay away from them.  Many manufacturers recommend that instead you use non-coated ring-shank or spiral-shank nails.  You can also use divergent chisel-point staples that are designed for fastening underlayment.

Tracking Stains: These are staining agents carried onto the floor by means of foot traffic.  The actual staining agent cannot always be detected but the discolorations have identifying characteristics.  Tracking stains will typically be in the traffic area or work area of a room while the non-traffic areas are not exhibiting the same discoloration.  The discoloration will usually be in the top area of the floor and not in the embossed areas (lower areas) such as grout lines.