How to Frame a New Doorway Between Existing Walls

Run a stud finder along the wall and mark the location of the studs onto the wall with a pencil. Measure and mark off the size of your opening, adding 1-1/2 inches to the height of the opening. Use a level to make sure your horizontal lines are level and the vertical lines are plumb. If you'll be putting a door into your opening, make sure that the area marked off is large enough to accommodate the door's roughed-in dimensions, which includes the frame and casing of the door. These dimensions will be listed on the door when you purchase it.

Tape plastic sheeting around the area to isolate the work area as much as possible from the rest of the house. Wall destruction can be dusty and dirty work. Place a drop cloth on the floor in the area where you'll be working.

Turn off the electricity to the area you'll be working on at the main circuit breaker panel, shutting down power to any outlets or lights on the wall.

Knock a hole in the top center of the marked area with a hammer. Cut outwards from the opening with a reciprocating saw. Work across and downwards with the saw, cutting through and removing the studs, until you reach the studs on either side of the planned width of the opening. When you reach the bottom, cut through the bottom plate of the stud wall until you reach the subfloor, peeling back or removing any flooring material on either side of the opening first.

Cut two two-by-fours to place on the sub floor. Each piece should extend from the nearest stud to the planned opening dimensions. Butt these bottom plates against the studs and nail to the sub floor with 10d nails.

Cut a top plate for the door frame opening from a two-by-four piece of lumber. The piece should be wide enough to fit at the top of the opening between the studs on either side. Position the top plate between the studs, with the bottom edge of the board even with planned height of the opening. Toe nail the board into the studs.

Cut two two-by-four boards to match the distance between the top and bottom plates. Position each board on the sides of the opening, even with the end of the bottom plate. Check the plumb of each board with a level and toe nail the boards into the top and bottom plates. The opening has now been framed.