Which Direction Should You Run Your Hardwood Floors?
While personal preference is a factor, the direction in which you run hardwood flooring boards will often be determined by structural and visual limitations. Visual congruity requires the boards to run away from the main entrance of a room, but structural integrity mandates that they run perpendicular to the floor joists. Therefore, you won’t necessarily always have a choice. When installing a floor in an entire house, the structural requirement may constrain you to maintain a certain direction throughout unless you fortify the subfloor.
Running the flooring boards from the main entrance of a room toward the opposite wall simplifies the sightline and makes the room appear less busy, which is why this is usually the most popular choice. When you are installing a floor in an entire house, the main entrance is usually the sightline reference, and the boards run away from it. If you maintain the same direction throughout the house, the boards may run across the entrances of some rooms. Although you can always change the flooring direction in doorways to prevent this, you must also take joist direction into account.
Flooring experts recommend installing flooring boards perpendicular to the floor joists in a house with a plywood subfloor. Installing them parallel creates the possibility that the floor will sag between the joists and open gaps between the boards or worse. If you prefer a layout that requires the boards to run parallel to the joists, you need to shore up the subfloor by adding a layer of 3/8″ of plywood. Older houses with 1-inch planks running diagonally to the joists can support flooring planks running parallel to the joists. If the subfloor is a concrete pad, these structural considerations don’t apply.
Diagonal Floor Installation
A diagonal installation is as stable as one that runs perpendicular to the joists, and it creates an interesting visual effect that works especially well in large rooms. While a 45 degree diagonal is the most common, it isn’t the only possibility. A floor that is slightly skewed with respect to a wall by about 10 degrees may help tie that wall visually to one in another room and create a unifying principle. Diagonal installations are more work and require more wood, because you produce more unusable offcuts when making angled cuts.
Other Things to Consider
When laying out the first row of flooring, it’s important to take into account the possibility that the walls aren’t straight. If you use a doorway or single wall as your sole reference, you may find yourself compensating for a large angle at the end of the installation. This not only makes more work for you, but also affects the appearance of the floor. The ideal direction for the flooring may therefore be at a slight angle with respect to a doorway rather than perpendicular to it. To find the angle, you’ll need careful measurements of the walls in all the rooms in which you run flooring.