White Line Syndrome - Hardwood Conspiracy or Common Finish Problem?

HardwoodFloorsMag.com, the official magazine of the National Wood Flooring Association, put up a really interesting article recently titled "What is Really Causing White Line Syndrome?"

Now, unless you're a hardwood flooring contractor, you probably aren't familiar with the term. White line syndrome, or WLS, is the term used to describe white lines that show up between boards in a wood floor. As the article explains, many contractors are seeing more instances of WLS and are placing the blame on finish manufacturers:

"[White line syndrome] seems to be so much more prevalent in recent years, particularly about the last five years. Some contractors who have never had issues with white lines before report suddenly having to redo floors, even though they’re doing everything the exact same way—with the same products they always have used.
This has all led to suspicions directed at the finish manufacturers: They’re changing product, using cheaper ingredients, messing up the finishes to comply with VOC laws, etc., etc. Contractors feel they are being thrown under the proverbial bus."

White line syndrome can occur when finish starts to peel away from the board edge.

As the article points out, however, the answer may not be as easy as blaming the finish manufacturers. Trends in consumer preferences and installation techniques also play a role:

"Trends in recent years toward exotic floors, dark floors and plank floors all make WLS more visible. A white line between boards may not even be noticeable on a maple floor, but it will be front and center on a walnut, padauk or dark-stained floor. Plank flooring expands and contracts more than strip, stretching the finish more, and many exotic species are also known for their volatile expansion and contraction on the job site.
Today’s more urgent job sites also may play into WLS. In the olden days, wood floors were installed and sat on a job site for a while before they were sanded and finished. Today, jobs tend to be more rushed than ever, and the wood may still be settling in—in particular, shrinking—while the finish is still flexible and drying.
Finally, customers’ expectations are ever-increasing. As they become more demanding, fewer imperfections are seen as normal, making life more difficult for everyone."

Like most hardwood flooring problems, the chances of experiencing white line syndrome drop dramatically when the floors are properly installed and maintained. Visit the Maintenance Links and Resources page on the Fantastic Floor site for more information.