Adding Support for a Load-Bearing Wall

Doors and Windows

• 1

  Add support in a load-bearing wall for a door or window. Use headers, horizontal boards fastened between two vertical studs and additional studs for support underneath the opening. Make headers for most door and window openings with 2-by-6-inch boards sandwiched around a 1/2-inch strip of plywood or oriented strand board.

• 2

  Nail the header with 16d framing nails and a hammer horizontally at the top of the opening. Level it with a level. Support it with studs cut with a circular saw to fit between the bottom of the header and the top of the wall bottom plate. Brace it with additional studs between the top of the header and the bottom of the top wall plate.

• 3

  Support a window opening with a header, but add a sill plate horizontally between studs at the bottom of the opening. Make the sill out of 2-by-4-inch boards nailed together through the 4-inch sides and nailed to studs on either side. Add short studs on both sides between the bottom of the header and top of the sill, and between the bottom of the sill and top of the wall bottom plate.

Open Spaces

• 4

  Support a load-bearing wall across wide open spaces with a header or beam. Make a header from 2-by-8 or 2-by-10-inch boards, depending on the width of the opening, or use a prefabricated truss or beam.

  Install a pre-built beam for long openings; beams typically have top and bottom plates of 2-by-6 to 2-by-8-inch boards sandwiched around oriented strand board or solid lumber set on the narrow edge.

• 5

  Install beams on 2-by-4 or 2-by-6-inch studs on both sides of the opening. Use doubled studs, two boards nailed together through the wide faces. Position the beam at the top of the opening, just below the top plate of the wall, and fasten it with nails through the sides.

• 6

  Brace a beam with doubled studs, two boards nailed together, installed vertically on each side of the beam between its bottom and the floor plate. Use 4-by-4-inch posts instead of 2-by-4s in a basement or on a porch or deck covering.

Adding to a Wall

• 7

  Add extra support to an existing wall with additional vertical bracing where the configuration is not changed by a new opening. Install extra studs between existing studs on 16-inch centers, for example, to brace the top plate of a wall to support added weight, such as a new attic air conditioner. Toenail these with framing nails diagonally through the studs into the wall plates.

• 8

  Increase bracing on a basement or outdoor load-bearing wall with diagonal supports. Reinforce the support for walls under a porch roof with braces of the same size lumber as the basic wall.

  Cut 45-degree angles on each brace and nail them diagonally between the post and the top frame of the roof or other structure. Use a similar technique on house walls where the braces will be covered.

• 9

  Boost support of an existing wall by "sistering," or basically building another wall and installing it parallel to and fastening it to the original wall. Add to the top plate as an alternative. Brace the joists or perpendicular beams resting on the top plate temporarily with 4-by-4-inch posts. Cut the tops of each stud with a reciprocal saw to allow a second 2-by-4 to be slipped in under the top plate. Nail the addition to the top plate and studs. Remove the temporary braces.