A wall frame is made up of horizontal and vertical boards. Understanding how to frame a wall starts with knowing its parts. (Follow your local building codes for specific measurements.)

• Top plate: A horizontal support that anchors a wall to the ceiling.
• Bottom plate: A horizontal support that anchors a wall to the floor.
• Vertical stud: Connects the top and bottom plates to form the frame. Vertical studs are 16 to 24 inches apart. 16 inches is the most common because insulation and other materials are also 16 inches wide.
• Blocking or fire blocks: Perpendicular supports between the vertical studs. Blocking is usually 48 inches from floor.

The basic tools and materials for framing an interior wall are:

• Circular or miter saw
• Framing hammer or power nailer
• Tape measure
• 16d framing nails or screws (nails are recommended because screws can break under pressure)
• Shims
• Stud finder
• Carpenter square
• Plumb bob
• Chalk line
• 2-inch x 4-inch or 4-inch x 4-inch structural lumber boards

Tip: If you have 3 or 4-inch diameter pipes running through the wall, make the wall from 2-inch x 6-inch dimensional boards. If not, make it from 2-inch x 4-inch boards.

Framing a wall correctly requires good planning and accurate measurements. Here’s how to properly measure where your wall will go:

• Use a chalk line to mark where you want to place the new wall along the floor.
• Run a stud finder along the ceiling to locate the joists.
• If the joists are parallel to the new wall, adjust the layout so that the wall is directly under a joist.
• If the joists run perpendicular to the wall, an adjustment should not be necessary.

Next, measure where the wall plates will go. Use a tape measure to mark the locations of each plate.

• Measure from a corner of the room and mark where the new wall will meet the existing wall.
• Measure from the opposite corner and lay out the other end of the new wall.

If the ceiling joists are perpendicular to the wall, mark each one where the top plate will intersect with them. This will make sure that your nails go into the joists, not just the ceiling covering.

To lay out the sole or floor plates of the new wall, drive a nail into the ceiling close to one end of the chalk line.

• Hang a plumb bob from the nail and mark the floor where it points. Repeat at the other end of the ceiling chalk line.
• Snap a chalk line between the marks to lay out one edge of the sole plate.
• Mark an "X" to the side of the line where the plate will be positioned.

Tip: If you're nailing into concrete, fasten the wall with construction adhesive and concrete nails.

The vertical wall studs will support the frame of the new wall. Here’s how to measure for them:

• Set the top and sole plates side by side on the floor.
• Starting at one end, measure and mark the plates every 16 inches.
• With a combination square and a pencil, extend the lines across the plates.
• Draw an "X" at the end of each plate and to the right side of the line on each plate to mark the stud locations.

Calculate the length of the vertical wall studs.

• Determine the stud length by measuring the distance between the ceiling and the floor at several places.
• Take the shortest distance and subtract 3 3/4 inches to allow for the combined thicknesses of the top and sole plates. This also allows for the clearance you'll need to tilt the wall into place.

Now that you have all your measurements, it's time to cut and assemble the studs. Most wood studs will have at least a slight bend or bow in one direction. This is called "crowning." If the first stud (or any other stud) is warped, make sure the crown faces up. Following this step when you frame a wall will make it easier to build. The stud won’t rock when you’re nailing it. You’ll also have a smoother wall surface because alternating crowns and cups (the opposite edge from a crown). Otherwise, there’ll be a wavy surface in your wall coverings.

• Look down the length of each stud. Determine which is the crown side.
• Lay out your wall with all of the crowns pointed up.
• Cut the studs to length with a circular saw or hand saw.
• Lay the bottom plate and the first stud on edge and nail them together with 16d nails.
• Complete the new interior wall frame by nailing the wood studs to the sole plate.

Safety Tip: Wear safety goggles whenever using a circular saw or other power tools.

• Nail the studs to the sole plate one at a time. Once all the studs are attached to the bottom plate, set the top plate on edge and nail it to the studs at the marks.
• Place blocking between the vertical studs. Cut them to fit, position them to make nailing easy, then nail them in place.

Blocking acts as a firestop in case of a fire inside the wall. A good practice is to add additional blocking inside the wall in places where you know things will be hung. For example, if the wall is to be part of a home theater, add reinforcement where the TV will be mounted. If it's a utility room, add extra supports for hanging shelves or cabinets. Supports of this type don't have to be limited to additional 2x4's, 3/4-inch plywood can cover a large area and provide a great deal of flexibility for future projects.

Now that you’ve completed the first part of building an interior wall, it’s time to lift the wall into place. Make sure you have someone to help you, especially if it is a large wall.

• Align the bottom plate with the floor chalk line.
• Carefully tilt the wall into place and align the top plate with the ceiling chalk line.
• Fasten the wall into place. Starting at one end of the new wall, shim between the top plate and ceiling, and check the wall for plumb with a level.
• As you shim and plumb each section of wall, drive 16d nails through the top plate into the framing with a hammer or nail gun.
• Fasten the bottom plate by driving 16d nails through it into the floor.
• Nail the end studs to framing in the existing wall.
• Score the shims with a utility knife and snap them off flush with the plate.
• Once you have finished wall framing, you can move onto installing insulation and drywall.

Tip: Wing walls that are only a few feet high and a few feet long can present challenges. You can strengthen one by running the end stud through the floor and bolting it to a joist.