How to Rough in an Opening for a Door

To rough in an opening for a door you will need careful planning and decisive execution. "Measure twice, cut once" as the saying goes. Assuming you have already built a wall, all you need to do is measure the door and modify the framing accordingly. You will remove intervening studs, install jack studs and a header, and top it all off with cripples for load support above. What you will end up with is a standard door opening with a sound design.

Instructions

1. Measure the height of the door to be installed and add 2 inches for the doorjambs, shim and the floor. Then measure the door width and add 2 1/2 inches for doorjambs and shims. Check your work: All standard doors are 80 inches tall and 24, 26, 28, 30, 32 or 36 inches wide.

2. Measure and cut three 2-by-4s to the height of the door plus 2 inches as measured in Step 1. These will become your jack studs.

3. Remove one or two adjacent studs from the existing wall where you want your door to go. If the existing studs are 16 inches apart, remove two. If the studs are 24 inches apart, remove one. Measure the width between the two existing king studs surrounding your door opening.

4. Measure and cut two 2-by-6s to the width of the opening you made in Step 3. Measure and cut a 1/2-inch piece of plywood about a half-inch shorter and about a half-inch narrower than the 2-by-6s. Make a board sandwich with the plywood in the middle and nail the sandwich together securely. This will become your header. It will rest on the jack studs.

5. Nail a jack stud to the left king stud.

6. Nail the other two jack studs together. This will be the right side of your door opening. Toe-nail this double jack stud to the bottom plate of the wall frame. The distance between the left jack stud and the double jack stud should be the the width of the door plus 2 1/2 inches, as measured in Step 1.

7. Place the header on top of the jack studs. Nail the header into place through the king studs. Toe-nail the header to the jack studs.

8. Measure the distance between the header and the top plate of the wall frame. Cut one or two 2-by-4s to this size. Cut two if you removed two studs in Step 3 and one if you removed one. These pieces are called cripples. Slide them between the header and top plate to create mini-studs that continue the pattern of the existing wall. Toe-nail them in place.

9. Cut the floor plate of the wall frame away from the door opening with a handsaw and you're finished.

Tips & Warnings

• Toe-nailing is easy if you hold the nail perpendicular to the surface, tap it a few times with the hammer until the point bites into the wood, and then shift the nail to 45 degrees for the final descent.

• If you'd like, you can attach the header to the jack studs and erect them all as a unit before securing it in place and adding cripples.

• Your measurements must be exact. Do not leave out any pieces. Not only is this for safety and structural soundness, but drywall sheets come in standard sizes and require predictable contact points to the framing.