How to Replace a Girder

Replacing a girder is strategic work and requires contruction skills.

Rotting girders can be very problematic within your home and can even cause your floor to sag. Replacing a rotted girder as quickly as the problem is discovered is important for preventing further damage to your home. Though multiple methods can be used based on the cause of your girder rotting, these are the basic steps to be taken when fixing a girder. Replacing your rotted girder may require a trip to the hardware store and lumber yard in your area.

Things You'll Need

• Jacking timbers
• Reciprocating saw
• Copper naphthenate preservative
• 4 pressure-treated 2 by 8 girders
• Nails
• Hammer
• Steel joist hangers

Instructions

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.

Tips & Warnings

• Before replacing your girder, consider having it looked at by a professional in order to determine the cause of rotting. Termites, among a few other unknown issues, will require variations in the girder replacement process.

• Any existing rot-producing fungi is dangerous to work with without proper ventilation. Open any operable windows should be opened. Using a fan or ventilation mask will also reduce risk of inhaling dangerous bacteria.

References

• YouTube: Replacing Rotten Floor Joists
• Home Repair Forum: Proper Way to Replace Rotten Floor