How to Replace a Girder
- 1). Support your floor joists or concentrated loads as carried by the girder by jacking timbers set under joists on either side of your girder. Raise the jacking timbers just enough to relieve the load carried by your girder.
- 2). Cut joists or floorboards that have previously been nailed into the beam with a reciprocating saw before attempting to remove the beam.
- 3). Soak exposed faces of old joists with a preservative to prevent further rotting. Secure the new beam into place by nailing together four pressure-treated 2 by 8 girders.
- 4). Raise the center of each plank up slightly to tension the center of your beam before face-nailing it to the others. This step will keep your new beam from sagging.
- 5). Saw through and reattach any floor joists that are mortised into the girder by using steel joist hangers. Old joists may require a trip to your local welders for custom-made joist hangers.
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