Beam and Girder Repair
At Foundation Repair by Alex, most of the calls we get start with something small: a door that sticks in the summer, a floor that feels a little bouncy near the kitchen. Sometimes it’s a beam or girder underneath the house that’s already failing. These are the horizontal wood members that carry your floor joists.
When one sags, cracks, or rots through, everything sitting on top of it moves with it. The girder is usually the main beam running down the center of the crawl space, picking up the load from the joists on either side. Smaller beams may run perpendicular to it or support specific spans.
Signs your beam or girder needs a look
- Floors that feel springy or bounce when you walk across them
- A gap opening between the baseboard and the floor
- Interior doors that stick in humid months and free up in dry ones
- Visible sag along the beam from the crawl space access
- Cracks in drywall or tile above the affected span
- Soft, spongy spots underfoot in one area of a room
None of these alone means a structural problem. A sticking door can just be a humid August. But two or three together, especially if new, are worth a crawl space inspection.
What actually causes beam failure
In our part of North Carolina, the most common culprit is moisture. Crawl spaces without a proper vapor barrier stay damp most of the year, and that humidity gets into untreated wood. Add a slow plumbing leak or poor grading outside, and you get conditions that support wood rot and eventually termites.
We also see beams that were undersized for the span they carry, common in older houses built before code required larger lumber. Less often, a support post settles into soft soil, and the beam above it sags.
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How we fix it
| Repair method | Best for | What it involves |
|---|---|---|
| Sistering | Cracked or partially weakened beam, still sound overall | Bolting a new beam alongside the damaged one to share the load |
| Full beam replacement | Wood rotted or termite damaged beyond repair | Supporting the floor, removing the old beam, installing treated lumber or steel |
| Adjustable steel columns | Sagging caused by a settled or missing support post | Setting columns on concrete footings to lift and support the beam |
| Helical or push piers | Support posts settling in poor soil | Driving piers to stable soil or bedrock, then transferring the load onto them |
For column work, we typically install systems from Foundation Supportworks, including their SmartJack and PowerBrace lines, or comparable columns from Earth Contact Products. For pier driven support in unstable soil, we've also worked with Ram Jack systems.
Which one we recommend depends on the load the beam carries, the crawl space height, and what the soil is actually doing, not just what's cheapest.
What the process looks like
We start with an inspection and measure the sag with a laser level, not a guess. From there we identify whether the problem is the beam itself, the support underneath it, or both.
If replacement is needed, we jack the floor back to level gradually, over days rather than all at once, since moving it too fast can crack drywall and tile that would otherwise survive the repair. Once the new beam or columns are in place, we check the level and document the work.
If you're feeling a bounce in your floor or a door won't close right anymore, have someone look underneath before you replace flooring or repaint over a crack. We'd rather tell you it's nothing than let a small beam problem turn into a floor replacement.
