How to Repair a Rotted Door Jamb

Sooner or later wood will rot in the most inconvenient places on the home. Most often you will find wood rot at the bottom of door jambs. Doors do not have to be replaced due to a water-logged door jamb. Once you know how to repair a rotted door jamb, you can have your door looking like new. Standard salt-treated lumber will replace rotted portions of the door jamb and save you money.

Things You'll Need

• Phillips-head screwdriver
• Small flat pry bar
• Pencil
• Carpenter's square
• Reciprocating saw
• Tape measure
• 1x6x8 salt-treated wood
• Circular saw
• Drill
• 3-inch long decking screws
• 1x2x8 salt-treated wood
• Hammer

Instructions

1. Use a Phillips-head screwdriver to remove the screws that secure the threshold at the bottom of the door opening. Pry the threshold up using a small flat pry bar. Use a utility knife to cut the paint seal between the inside door trim and the inside wall. Insert a small flathead screwdriver between the trim and the inside wall, and carefully pry the inside trim off the wall.

2. Insert the flat pry bar between the outside trim and the wall to pry the outside trim away from the wall. You do not have to remove the outside trim completely. Pull it away from the wall to allow room for the reciprocating saw to cut the rotted door jamb.

3. Make a mark with a pencil 3 inches above the last area of rot on the door jamb. Use a carpenter's square to draw a straight line at your mark. Use a reciprocating saw to cut the rotted jamb at the line you marked. Cut the jamb up to the original door framing. Pry out the rotted wood with the pry bar.

4. Measure the height from the floor to the bottom of the cut with a tape measure. Cut a piece of 1x6 salt-treated lumber to the measurement with a circular saw. Dry fit the 1x6 into the cut out area, and notch the bottom out as necessary for the sill.

5. Drill pilot holes into the 1x6 with a drill and bit slightly smaller than the diameter of the decking screws you are using to attach the board. Secure the 1x6 to the door framing using the decking screws and a screwdriver.

6. Cut the piece of 1x2x8 salt-treated wood to the same measurement you cut the 1x6 piece. Close the door, and mark a line with the pencil from the remaining door jamb stop to the floor. Open the door, and line up the edge of the 1x2 with the line. Drill pilot holes through the 1x2 and the 1x6, and secure the 1x2 using the decking screws and a screwdriver.

7. Reattach the bottom threshold back into the floor. Reattach the inside and outside trim pieces by tapping them back into the wall with a hammer.

Tips & Warnings

• Paint the replacement jamb as soon as possible with matching paint.

References

• Hammer Zone: Reparing Door Jambs