DIY Network

How to Repair a Load-Bearing Beam

Follow these instructions to properly repair a damaged load-bearing ceiling beam.

More in Windows Walls and Doors

repairing a load bearing beam
  • Time

    Under Half Day

  • Price Range

    $50 - $100

  • Difficulty



Step 1: Take Safety Precautions

  • Consult a licensed contractor or architect before removing any part of your home.

  • Turn off any electrical wiring in the area, and check for plumbing and wiring.

  • Have a licensed electrician move or remove any wiring which may be problem.

  • Always add bracing to support any structural area of a home before altering it.

  • This project is a 2-person job -- don't attempt it alone.

take safety precautions when altering wall

Step 2: Remove Drywall and Insulation

Once the bracing is replaced and any problematic wiring has been removed, take out the drywall and insulation around the area to be replaced. Use a chalk line and reciprocating saw to keep your drywall cuts as straight as possible (Image 1). Tear drywall from ceiling (Image 2) and replace insulation that has fallen as needed.

Step 3: Build the Support Beam

You should build your support beam in advance of removing any support to eliminate the down time between the removal and replacement of support. Measure the length of the space to be spanned and allow at least 8" extra for setting on top of supports on each end.

In this demonstration, we used used 2" x 8" lumber with a piece of 1/2" plywood sandwiched in between to create the support beam. Cut the 2" x 8" lumber to proper lengths. Then, with a table saw, cut the 1/2" plywood into pieces 7 1/8" wide -- slightly less than the width of the 2" x 8"s. Cut enough plywood to extend the whole length of the 2" x 8"s. Lay the pieces of plywood between the two 2" x 8"s, making sure the plywood does not extend outside the edges. First, apply a generous amount of wood glue for extra reinforcement; then nail both sides of the new beam with 1-3/4" nails, using 3 or 4 nails per foot for strength.

build support beam in advance

Step 4: Clear the Area for the Beam

Use a circular saw to take out the area under the joists where the new beam will fit. If necessary, cut through the joists to allow enough space for the beam to fit.

clear area for beam

Step 5: Install the New Beam

Angle the crown (the natural curvature of the boards) upward to keep the ceiling from bowing. Then attach the beam to the joists with nails. For added support, nail a joist hanger under each joist into the beam, making sure the hangers do not extend below the new beam.

Once the beam has been secured, remove the bracing and replace the drywall.

install new beam