Pier and Beam Repair for San Antonio's Raised Floors
A pier-and-beam house sits a foot or two off the ground on a grid of supports. When one of them sinks, rots or loses its shims, the floor above dips, bounces or tilts. Pier and beam foundation repair is about getting every support carrying its share of the floor again.
Fixr's 2026 guide puts pier and beam foundation repair at $2,000–$15,000. Within that, leveling a sagging floor over a crawl space runs $1,000–$5,000, replacing a support beam $1,500–$5,000 each, and replacing a floor joist $100–$300 each (Fixr, 2025). A reshim with no wood replacement sits at the low end.
What holds up the floor
From the ground up: a concrete pad or footing, a pier on top of it (concrete block, poured concrete, or in some very old houses a wood post), then a beam running across a row of piers. Floor joists rest on the beams, the subfloor rests on the joists, and the outside walls sit on a perimeter beam or a sill. Between pier top and beam, thin wood wedges take up the slack. Every one of those layers can shift, shrink or rot.
Why raised floors drift out of level here
- Pier pads move with the clay. A pad sitting in shallow clay rises in a wet spell and drops in a drought. San Antonio's hot, dry Julys and Augusts, followed by wetter Septembers and Octobers (NOAA 1991–2020 normals), work the ground around them every year.
- Shims shrink and crush. Wood shims dry out, compress under load and slip, leaving a beam resting on nothing.
- Beams sag over long spans. Older framing often has fewer supports than a newer house would.
- Moisture and leaks. Poor crawl space drainage, blocked vents or a plumbing leak under the floor soften wood and the soil under the pads.
What pier and beam foundation repair involves
Reshimming jacks the beam up and replaces loose or rotted shims with new hardwood or steel ones. Added supports go under beams or joists that span too far. Replacing failed piers means setting new ones on a better footing or driving them deeper. Sistering bolts a new joist alongside a cracked or sagging one, and badly rotted beams are replaced outright. A good job also fixes what caused the damage: water pooling under the house, missing vents, or a leaking line.
Getting the crawl space ready for a look
Make sure the access opening is clear and note where the floor feels soft, slopes or squeaks most. Mention any musty smell or past plumbing leaks. With about 43% of San Antonio's homes built before 1980 (U.S. Census ACS 2020–2024), many crawl spaces carry decades of patches, so ask the specialist to explain which supports are original. Typical prices for each repair are in the foundation cost guide for San Antonio.
Questions homeowners ask
Do raised floors need reshimming again later?
There is no fixed schedule. It depends on how much the soil under the pads moves and what the shims are made of. Houses on active clay may need an adjustment after a big swing between drought and heavy rain. Ask what material the new shims will be and how they are held in place.
Have someone look at the house
Tell us what you have noticed and where: the crack, the door, the floor. One independent foundation specialist who works in San Antonio will phone you to talk it over and set a time to see it.