Width Variations - Wide Plank Hardwoods

You’ve finally decided on the type of prefinished hardwood flooring you’d like installed in your home or other property. You researched what species would work best in your place, and spent hours deciding which company to purchase the hardwoods from and who’d install them. You may have even decided to do the install yourself. But once your hardwoods arrive, or maybe after you’ve laid down a few or more, you notice something odd: after placing two planks side by side, you find the widths of each aren’t quite the same -- maybe not even by a little bit.

What’s up with that?

Variations in the widths of prefinished hardwood flooring planks is one of the biggest complaints those on the hardwood flooring retail and distribution end of things hear from customers. But, there are several explanations for this what seems to be discrepancy -- explanations that go beyond the unfortunately all too familiar shoddy manufacturer or contractor stories.

Natural Wood

For one, hardwood flooring is made out of real wood, not a plastic mold. It’s a natural product, and as such, isn’t perfect. Wood contains natural imperfections and responds to changes in its environment, including fluctuations in moisture - which is part of what gives hardwood flooring its beauty and charm. Woods shrink or expand depending on the humidity levels of a space. So, although the widths may be a little off before or during installation, it’s not necessarily due to poor milling or a bad install. It could just be the moisture content in the woods at the time they were manufactured or laid out. This is mostly an issue for wide hardwood flooring planks, like the 5” products. Narrower boards generally are not as impacted.

Less Stable Species

Some species of hardwoods are more stable than others. You may be dealing with one of the lesser stable species. This means that some are more prone to greater amounts of shrinking and expanding as the seasons or the indoor temperatures shift. Let’s take Brazilian Teak and Brazilian Walnut for example. Although beautiful and the most dense of the hardwood flooring world, these two species are the top two when it comes to width variation issues.


Faulty Measuring

Though the widths of the two boards you placed side by side may seem way off, it’s possible your eyes are playing tricks on you.  Simply eyeballing the planks may not be enough to determine how off the widths may be. Once you actually take out the proper tools and make a measurement, you may find the widths aren’t as distant as you may think. While a tape measure could do the job, you may not get as accurate of a reading for the teeny tiny measurements. Instead, try to go with a caliper, which can take on smaller measurements like up to one, one-thousandths of an inch. Make sure as well to measure the moisture content when measuring the woods, as the two go hand in hand - the latter changing in response to the former.

What Kind of Gaps Are We Talking About Here?

While different hardwood flooring planks can shift as described above, and can be considered unsightly, annoying, and potentially disruptive to your floors, the spacing is not in inches, but instead fractions of an inch. They are not large enough that when walking over them you’ll fall through the floor. The gaps are small. The widest would be 1/16th of an inch. For comparison, the first mark on most tape measures is 1/8th of an inch. Most of the time, the gaps will be less than 1/32nd and 1/64th of an inch.

Top 3 Ways to Minimize the Potential for Gaps

With hardwoods shifting in response to temperature changes, gapping between the boards may result.  How do you minimize the chance of this happening? Whether you’re installing the hardwoods yourself, or having someone else do it, the following should occur:

1. Start the install with straight runs, not against a wall.
2. Properly acclimate the flooring. The longer you acclimate the better when it comes to wide width products.
3. When nailing the boards down, make the nail pattern tight. Keep the spacing close together.

The widths of prefinished hardwood flooring planks may not be completely equal due a variety of factors, including moisture content, faulty measuring, the particular type of wood species used and the structure of the space where they woods are to be installed.