Twenty five years ago the vast majority of solid hardwood flooring sold in the Midwest was 2 ¼” wide. Over the years, consumers became more adventurous and began using 3 ¼” solid flooring. Today, 5” wide solid flooring is becoming increasing popular. Starting out as mostly dark stained, hand scraped offerings, wide plank flooring is now becoming trendier in smooth-faced flooring boards with lighter hues. This trend creates some challenges for flooring dealers, many of whom have not been properly introduced to wide plank solid flooring.
Solid wood flooring in the upper Midwest has always created some challenges due to its propensity to expand and contract with changes in moisture. Homes in the upper Midwest have the widest humidity swings of anywhere in the country. It is common for the relative humidity in homes here to range from an arid 15% in the winter (forced air heat with no humidifier) to a clammy 70% in the summer (when the windows are open on a stormy day). This change in humidity can result in an 8% change in the moisture content of the wood flooring. This, in turn, according to the United States Department of Agriculture, can result in a 1/16” change in the width of 2 ¼” oak flooring, which in turn leads to seasonal gapping of 1/16” between each board. This is noticeable.
Herein lays the challenge of wide width solid hardwood flooring. While a sixteenth of an inch on 2 ¼” oak flooring may get some folks excited, think about what this means when the customer has 5” oak installed in her house. The seasonal gaps in the above example now become 1/8”. This will get almost everyone excited. When a consumer is purchasing a hardwood floor or a retail sales person is selling a hardwood floor, they often do not think about this fact; the wider the flooring, the wider the seasonal gapping is going to be. This makes having humidification control in a home even more important as the width of the solid flooring chosen increases. The only way to avoid these large seasonal gaps is to keep the relative humidity in a tighter range.
Minor width variance from plank to plank is another characteristic of wide plank flooring that consumers are often not expecting. As discussed above, hardwood expands and contracts with changes in moisture content. This phenomenon is not unique to installed flooring, it happens to lumber at the plant as well. The hardwood lumber is dried down to a moisture range of 6% to 9%, with some percentage falling slightly outside this target range. This corresponds to a relative humidity level in the home where the flooring will be installed of 35% to 55%. The lumber will maintain this moisture range as it runs through the plant and is processed into flooring. Flooring is milled to a standard width, with every board being nearly that exact width. Then, as the flooring acclimates, the widths of the finished product will change.
Boards that were on the higher side of the moisture range when processed (9% for example) may be placed in a lower humidity environment and dry down to 6%. When this happens, the width on the finished plank will decrease by 1/32”. Thus, when it is laid next to a plank that was processed at 6%, it will be narrower. This easily can be mistaken by an uneducated consumer as a milling defect. However, this is not a defect; it is an inherent characteristic of wide plank flooring. It is true of all hardwood flooring, but it is much more noticeable on wider boards as the expansion and contraction is amplified. A 2 ¼” flooring board (with the same moisture change as the example above) would experience only a 1/64” width variance. This would be much less noticeable.
When selling wide plank solid flooring, it is important to properly set the consumers’ expectations. There will be more noticeable seasonal gapping than there will be with narrower floors. There will likely also be some subtle width variance from plank to plank right out of the carton, for the reason outlined above. Special care should also be taken when installing wide plank flooring. It is imperative to keep the rows straight during installation so that the end joints do not appear askew. The installation should be started off a chalk line and not off of a wall, as starting off a wall will almost always ensure a crooked start. Additional chalk lines should be laid every few feet to make sure the installation remains straight. Small variances over the span of a room can become big variances.
Wide plank flooring will continue to grow in popularity here in the Midwest, as it has on the west coast. It is very important to educate your customer about the characteristics of wide plank flooring and set proper expectations. If you encounter a homeowner who wants wide plank flooring but finds the modest gapping objectionable, she may be a better candidate for engineered wood flooring, LVT, or laminate. It is better to find this out before the flooring has been installed in her home than after!