What You'll Need
I've got a door frame that's seen better days. The bottom section is completely rotten — soft, crumbly wood that's been soaking up moisture for way too long. If you've got the same problem, here's how to fix it without replacing the whole frame.
- Circular saw (or oscillating multi-tool)
- Wood chisel
- Hammer
- Tape measure
- Pencil
- Level
- Wood glue
- Screws (deck screws work well)
- Replacement wood (same thickness as your existing frame)
- Wood filler
- Sandpaper
- Paint or primer
Step 1: Cut Out the Damaged Section
First, figure out how far up the rot goes. Press a screwdriver into the wood — if it sinks in easy, that wood is gone. Mark a clean cut line about an inch above the highest damaged spot.
Set your circular saw blade depth to match the thickness of the door frame. Cut straight across the frame. Then make two vertical cuts on each side of the jamb to free up the rotted section. If you're working tight to the door trim, an oscillating multi-tool is way easier to control.
Step 2: Remove the Old Wood
Once you've made your cuts, use a hammer and chisel to knock out the damaged piece. You'll probably need to clean up the edges — just chisel away any splintered or uneven bits until you've got a clean, square opening.
Step 3: Cut Your Replacement Piece
Measure the opening you just made. Cut a piece of new wood to the exact same size. Match the thickness to your existing frame — this is important. If you're off by even a little, the repair will look obvious.
Test fit the new piece. It should slide in snug but not tight enough to bow the frame. If it's too tight, sand the edges down a bit.
Step 4: Install the Replacement
Put a generous bead of wood glue on the contact surfaces — both on the old frame and the new piece. Slide the replacement into place and tap it flush with a hammer (use a scrap block so you don't dent the wood).
Run a couple screws through the side of the frame into the new piece. Pre-drill first so you don't split anything. Countersink the screws slightly below the surface.
Step 5: Fill and Finish
Let the glue dry completely — give it at least a few hours. Then fill any gaps or screw holes with wood filler. Let that dry, sand everything smooth, and you're ready to paint.
One coat of primer, two coats of paint. Match the existing color if you can. If the frame is stained instead of painted, you'll have a harder time matching — paint is usually the easier route here.
That's it. You just saved yourself from having to tear out and replace the whole door frame. Takes maybe an hour of actual work, plus drying time. Way better than the alternative.
