Installing vinyl plank flooring creates a seamless, water-resistant surface that looks remarkably like hardwood but demands far less maintenance. The most critical detail for a truly professional finish lies in how you handle the transition beneath door jambs. Leaving a gap or a buckled edge not only ruins the visual flow but can also cause the planks to catch and wear prematurely under foot traffic and repeated opening of the door.
To achieve a look that mimics the solid, uninterrupted sweep of hardwood, you must pull the vinyl planks underneath the door frame. This method, often referred to as "floating through," ensures the floor flows visually from room to room and eliminates the lip that collects dirt and shreds vacuum heads. The key to success lies not in forcing the plank under the jamb, but in creating a temporary workspace that allows you to trim the piece to perfection before the final installation.
Understanding the Undercut and Transition
The goal is to create a reveal that is invisible to the naked eye. This requires you to undercut the bottom of the door jamb to the thickness of the vinyl plank plus the underlayment. By doing this, the plank can slide neatly underneath, hiding the edge and maintaining the height difference between rooms. Skipping this step usually results in an awkward overlap that feels uneven and looks unprofessional, no matter how well the rest of the floor was laid.
Tools Required for Precision
You will not succeed with a standard handsaw and a guess. The right tools transform a tedious chore into a precise maneuver. A dedicated undercut saw, which features a long, slim body and a flat soleplate that rides along the floor, is the industry standard. If you do not have one, a oscillating multi-tool with a wood cutting blade is an excellent alternative, as it vibrates side to side and minimizes the risk of gouging the hardwood jamb.
- Undercut saw or oscillating tool
- Shims or playing cards
- Tape measure and pencil
- Utility knife or pull saw
- Rubber mallet
- Safety glasses and dust mask
Step-by-Step Installation Process
Begin by measuring the total thickness of your flooring system, which includes the vinyl plank itself and any underlayment attached to it. Transfer this measurement to the door jamb, marking a clear line that represents how much material you need to remove. Place shims between the door and the jamb to hold the door slightly open, providing you with the necessary space to work comfortably and see your mark clearly without the door swinging shut.
With your cutting tool following the marked line, execute the cut slowly and steadily. It is better to cut too shallow than too deep; if you cut into the subfloor, you will have a much bigger problem than a tight jam. Once the cut is complete, test the fit by sliding a vinyl plank into the gap. You want the plank to disappear from view, sitting flush with the jambs on both sides of the doorway. Use a utility knife or a small pull saw to remove any splintery wood or stubborn fibers that prevent the plank from seating properly.
Trimming the Plank for a Clean Finish
Before you attempt to slide the plank under, you must cut it to length. Do not try to force a full, uncut plank under the jamb, as the compression will buckle the floor and lock the door in place. Measure the distance from the existing flooring wall to the undercut area, and mark the back of the vinyl plank. Score the surface deeply with a utility knife and snap the plank cleanly. This ensures a sharp, square edge that slides in smoothly without catching on the jamb.
As you insert the plank, use a rubber mallet to gently persuade it into place, ensuring it remains level with the rest of the room. If the door now scrapes on the threshold, you may need to trim a sliver of material off the bottom of the door or the edge of the plank. Once the fit is perfect and the vinyl sits flush, you can transition to the adjacent room, secure the last row of planks against the wall, and complete the installation with a finishing pass of transition trim or a smooth reducer strip to cover the seam.
