How to Undercut a Door Jamb When Installing Laminate Floors

Every room has a door, so knowing how to install laminate flooring when encountering a door is pretty important. A few months ago we produced a highly popular video entitled “How to Install Laminate Flooring Under a Door Jamb.” Today, we’re premiering a video that might be technically called a “prequel” … “How to Undercut a Door Jamb” … because you have to undercut the door jamb before you can install laminate flooring under it!

In this 4 min. 47 sec. video, we used a practice door frame set up in the Swiss Krono Atlanta facility to demonstrate the tools and techniques he uses to successfully cut and remove the bottom portion of a door casing. Doing this properly will allow the laminate flooring to slide underneath the door jamb for a nice, finished fit and appearance.

Terms you’ll hear in the video “How to Undercut a Door Jamb”

Casing: That’s the molding that makes up the door jamb.

Door Jamb: The casing that frames the doorway and hinges the door.

Door Jamb Saw: Also known as an undercut saw. Blades will be 18″ to 12″ and can cut in either direction.

Oscillating Blade Tool: A power hand tool that can be corded or battery powered. The blade moves slightly side to side up to about 20,000 strokes per minute.

Sill Plate: Or “sole plate,” it’s the 2 x 4 that’s attached to the subfloor. The wall studs are attached to the sill plate.

Stop: The part of the casing that protrudes out and stops the door.

What tools do you need to undercut a door jamb?

(Note: Be sure to watch the video “The Basic Tools for Installing Laminate Flooring” for more details on the tools you’ll see in this video.)

Door Jamb (Undercut) Saw: Check out the Brutus Undercut Saw at Home Depot

Oscillating Blade Tool: Check out Dremel®, Bosch®, DeWalt® or Balck & Decker® at Lowes

Pencil: We prefer a carpenter’s pencil for big, bold easy-to-see lines.

Chisel: Helps clear debris if needed.

Hammer: Handy to have if ever needed.

Scrap piece of the same laminate flooring that you’re installing: Keeps cut straight.

Dust brush, vacuum: You’ll generate saw dust. You must keep area clean and debri-free for a good fit.

Knee pads: You’ll thank yourself later.

Dust Mask: N95

Goggles: Your sawing action may kick-up dust in your eye–you don’t want that to happen!

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Post time: 11-09-2018