Almost every foundation conversation in south Louisiana starts with the same question: what is the house sitting on? The answer decides where the problem usually comes from, what it looks like inside, where the repair happens, and what a fair quote should list. This guide compares the two construction types side by side so you can read your own house — and the quotes you get for it — with more confidence.
Most Baton Rouge-area housing is slab-on-grade. Pre-1960s housing stock is often pier-and-beam. That rule of thumb holds across the Baton Rouge metro, but it is only a rule of thumb. Plenty of neighborhoods mix the two, and some individual houses are both.
The two types at a glance
The comparison below covers the points that matter most when something starts to move. Price rows are published ranges from Louisiana foundation companies, not quotes and not prices set by this site.
| Pier-and-beam (raised) | Slab-on-grade | |
|---|---|---|
| How it is built | Piers on footings support beams; sills and joists carry the floor above a crawlspace. | A concrete pad poured on the ground, usually with a thickened edge, carries the house directly. |
| How it moves | Footings settle, piers lean or crack, shims crush or slip, and wood softens where it stays damp. | Soil under part of the slab shrinks, swells, or settles, so one section drops or rises relative to the rest. |
| What you notice first | Bouncy or soft spots, a dip in a hallway, a slope toward the middle or one wall. | Diagonal drywall cracks at door corners, cracked tile in a line, stair-step brick cracks. |
| Where the repair happens | Underneath, from the crawlspace. | Below the slab, by excavating at pier locations — inside the footprint if needed. |
| Typical repair items | Re-shimming, resetting or adding piers, sill and beam replacement, crawlspace moisture work. | Exterior and sometimes interior piers, a controlled lift, drainage correction, crack and finish repair. |
| Moisture concern | Water standing in the crawlspace and damp air rotting wood and softening soil under footings. | Uneven wetting and drying of the soil under and beside the slab, plus any leak beneath it. |
| Published range | $3,000–$15,000 (house leveling) | $3,500–$12,000 (slab repair) |
How to tell which one you have
You can usually tell from the yard in a minute or two. Walk around the base of the house and look for:
- Vents or an access door set into the foundation wall or skirting — a crawlspace is behind them.
- Steps up to the front or back door, with the floor clearly above the ground.
- Piers or skirting visible around the perimeter on older houses, sometimes with lattice between them.
- A concrete edge showing at ground level, with the floor only a few inches above the yard — that is a slab.
Inside, a raised floor often sounds hollow and may flex slightly when you walk across it; a slab feels solid underfoot, and in a garage you can see the concrete directly. If you still are not sure, say so when you call. Confirming the construction type is part of any good evaluation.
Two repair paths, not one
Because the two types are built so differently, they are repaired in different places and with different tools. The short version:
Movement is corrected from below the slab — typically piers driven or set under the perimeter or interior and the slab lifted back toward level.
The house sits on piers above a crawlspace, so leveling is usually done from underneath — resetting or adding piers, shimming, and replacing rotted sills or beams.
On a raised house, the work is mostly carpentry and support adjustment, done a section at a time from below the floor. On a slab, the work is mostly excavation and piering, done around the perimeter and, where the low area is in the middle of the house, from inside. The pier-and-beam repair page and the slab foundation repair page each go deeper on their own path.
Moisture: crawlspace vs. under the slab
Water is the common thread for both types, but it shows up differently. Under a raised house, the risk is water that collects in the crawlspace and air that stays damp. Over time that can soften the soil under footings, so piers settle, and it can rot the sills and beams that sit closest to the ground. The fix often combines getting water out from under the house, improving ventilation or vapor control, and replacing the wood that has already failed.
Under a slab, nobody can see the soil, so the clues are outside and in the finishes. Downspouts that empty at one corner, flower beds built up over the edge of the slab, a patio that tilts toward the house, or a leak in a line under the concrete can all keep one part of the soil wetter than another. When soil under one part of a slab changes volume and the rest does not, the slab moves unevenly. The drainage and moisture correction page covers the usual fixes for both.
Mixed houses: a raised original with a slab addition
A lot of older houses in Louisiana have been added onto. A common pattern is a raised original house with a den, kitchen, or bedroom added later on a slab, or a slab house with a raised porch or sunroom. Each part follows its own rules, and the two can move independently.
That joint deserves special attention, because it is where trouble tends to collect:
- A step or slope in the floor where the old section meets the new one.
- A crack in the wall or ceiling that runs along the line of the addition.
- A door in or near the joint that drags or will not latch.
- Water that collects where two rooflines meet above it.
If your house has an addition, point it out. A good evaluation should check both foundations, the connection between them, and the drainage at the joint — and the quote should say which part of the work applies to which section.
What changes on the quote
Whatever the construction type, a quote you can compare should break the work into the same four separate lines:
- 1Evaluation findingsWhat was measured and found — elevation readings, crack locations, construction type, likely cause.
- 2Drainage / moisture correctionGutters, grading, downspouts, or crawlspace moisture work that addresses why the soil is moving.
- 3Structural repairPiers, shims, or sill and beam replacement — with counts, locations, and depths stated.
- 4Finish / cosmeticDrywall, brick, trim, and door adjustments after the house moves — priced on its own line.
What fills those lines is where the two types differ:
- Raised house: the structural line should say how many piers are reset or added, where shims go, and how many linear feet of sill or beam are replaced — and how hidden rot will be priced if it turns up once boards are exposed. The drainage line should cover crawlspace water and ventilation.
- Slab house: the structural line should give the pier count, split into exterior and interior, the pier type, the locations, and the lift target. The finish line should say whether flooring removed for interior piers is replaced.
- Mixed house: each section’s work should be identified separately, so you can see what is being done to the raised part and what to the slab.
The foundation repair cost guide has the published ranges by job type, including per-pier figures, and explains why two honest bids can differ.
If you are buying or selling
Construction type is one of the first things worth knowing about any house you are considering. For a raised house, ask whether anyone has been in the crawlspace recently, and what they found: standing water, soft wood, stacked or slipped shims. For a slab house, ask about any history of cracks, sticking doors, or plumbing leaks under the slab. For either, a written evaluation that states what was measured and the likely cause gives buyer and seller the same set of facts to work from.
The short version
A pier-and-beam house is lifted and supported from the crawlspace, and its weak points are moisture, wood, and settling piers. A slab house is supported from below the concrete on piers, and its weak point is uneven soil moisture under the pad. Both benefit from good drainage, both should get an itemized quote, and in both cases the cause should be named before anyone talks price. For how the two words for this work overlap, see house leveling vs. foundation repair, or call (225) 535-8057 and describe what you are seeing.
Pier-and-beam vs. slab: questions
Is a pier-and-beam or slab foundation better in Louisiana?
Neither is better in every case. A pier-and-beam house keeps the floor off the ground and is releveled from the crawlspace, but its wood and piers need ongoing attention, especially where moisture collects. A slab is simpler and has no crawlspace to manage, but when it moves, the repair means piers beneath the concrete and sometimes opening floors inside. Condition and drainage matter more than type.
How can I tell if my house is pier-and-beam or slab?
Look at the base of the house. Foundation vents, skirting, or a crawlspace access door, plus steps up to a floor that sits above the ground, mean pier-and-beam. A concrete edge at ground level with the floor sitting just above it means slab-on-grade. Some houses are both, usually where an addition was built later.
Which costs more to repair, pier-and-beam or slab?
It depends on the house, not the type. Published ranges from Louisiana foundation companies put house leveling at roughly $3,000 to $15,000 and slab repair at roughly $3,500 to $12,000. On a raised house, the amount of rotted sill and beam drives the price; on a slab, the number of piers and whether any are interior.