Sagging or uneven floors over a crawl space in the Birmingham area usually mean the framing underneath has lost support, and crawl space repair typically costs $2,500 to $8,000, according to HomeGuide's February 2026 crawl space repair guide. Sistering a weakened joist runs $150 to $325 per joist and replacing one runs $350 to $1,000, per HomeGuide's February 2026 sagging floor guide, while replacing a crawl space support beam runs $1,500 to $4,000. BDry Alabama measures how far the floor has deflected, sets adjustable steel support posts on stable footings under the sagging beams, and adjusts them gradually, and its floor support systems carry a two year warranty. A free inspection under the house sets the exact price.
We repair crawl spaces and sagging floors for homeowners in Birmingham, Hoover, and the surrounding towns. Reach out for local pricing and a free estimate.
Birmingham's housing is old by Alabama standards: Census ACS 2023 estimates put the median home at 1965, with about 42 percent of the city's 108,903 housing units built before 1960. The typical Birmingham home dates to around 1965 per Census data, roughly 61 years of Alabama weather and daily use. Call (205) 942-1976 or book a free estimate for Birmingham pricing. More on Birmingham
Hoover is a newer suburb: Census ACS 2023 estimates put its median home at 1994 across 39,090 housing units, with about 71 percent owner occupied. The typical Hoover home dates to around 1994 per Census data, roughly 32 years of Alabama weather and daily use. Call (205) 942-1976 or book a free estimate for Hoover pricing. More on Hoover
BDry Alabama handles crawl space repair in all 28 of these cities and the towns around them. Linked cities have their own local page. See every service area.
These are typical installed ranges from HomeGuide's February 2026 crawl space repair and sagging floor guides, not quotes. How many joists or beams are involved, what weakened them, and how much room there is to work under the house set your price, which comes from a free inspection.
| Crawl space repair | Typical installed range |
|---|---|
| Sistering a weakened joist, per joist | $150 to $325 |
| Replacing a damaged joist, per joist | $350 to $1,000 |
| Replacing a crawl space support beam | $1,500 to $4,000 |
| Structural engineer's plan, when required | $250 to $1,000 |
| Wet crawl space cleanup and repair | $1,500 to $5,000 |
| Subfloor replacement, whole floor | $2,000 to $7,000 |
| Major structural reinforcement | $4,500 to $20,000 or more |
Figures are typical ranges and vary by project. Your free estimate is exact.
BDry Alabama measures your project and gives you a clear written estimate at no cost.
We are a local foundation repair and waterproofing contractor and we stand behind every job. You are not handed off to a subcontractor. Every job follows the same disciplined process:
Floors sag from below, and the damage under most houses here is done in summer. NOAA's 1991 to 2020 climate normals for the Birmingham airport station put the July average low at 72.1 degrees, with about 65 days a year at or above 90. Air that warm and wet moves into a vented crawl space day and night and condenses on joists and girders cooled by the air conditioning above. Wood that stays damp season after season softens, and a beam that once carried the floor starts to deflect. The EPA's mold guide sets the target at below 60 percent relative humidity, ideally 30 to 50, and a crawl space that sits above that all summer is where bouncy and sloping floors start. Supports correct the sag; drying the space protects the repair.
In a house built over a crawl space, a sagging or uneven floor almost always starts underneath. The usual causes are joists and beams softened by years of damp air or wood rot, interior posts or piers that have settled into clay soil, or framing that was spaced too far apart when the house was built. Alabama's climate works on all three: NOAA's 1991 to 2020 normals give the Birmingham airport station a July average low of 72.1 degrees and 56.62 inches of rain a year, so crawl spaces here stay humid and the soil under the piers swells and shrinks. HomeGuide's February 2026 sagging floor guide lists other signs that travel with a sag, including gaps between baseboards and the floor, sticking doors, and cracks in drywall near corners. A look under the house tells you which cause you have, and BDry Alabama measures the floor so you see how far it has moved.
Crawl space repair typically costs $2,500 to $8,000, with a national average near $5,500, according to HomeGuide's February 2026 crawl space repair guide. Individual repairs vary widely: replacing a crawl space support beam runs $1,500 to $4,000, cleaning up and repairing a wet crawl space $1,500 to $5,000, and a structural engineer's plan, when a beam has to be replaced, $250 to $1,000. For sagging floors, HomeGuide's February 2026 sagging floor guide puts sistering a weakened joist at $150 to $325 per joist and replacing one at $350 to $1,000. Major structural reinforcement across a whole floor runs $4,500 to $20,000 or more. What moves a house up that range is how much framing is involved, what damaged it, and how much clearance there is to work. BDry Alabama gives you one written price after a free inspection.
Some unevenness is normal in an older house, but a sag you can measure deserves a look. HomeGuide's April 2026 floor joist repair guide gives a simple test: set a level on the floor in the low area, and a deviation of more than half an inch over four feet suggests a structural issue worth a professional inspection. A floor that bounces near the middle of a room, doors that no longer latch, cracks above door frames and gaps opening under the baseboards all point the same way. Left alone, a sag usually gets worse, because a joist or beam that has started to deflect carries load less well each year and can pass stress up into walls and trim. The fix is often modest: added support under a beam, or a few joists reinforced. BDry Alabama measures floor deflection so you know what you are dealing with.
They shorten the distance the framing has to span and carry the load down to stable footings. An adjustable steel post is set on a footing under the sagging beam, then tightened in small steps over time so the framing is corrected gradually instead of being jacked up all at once, which would put sudden stress on the structure. Once set, the posts give the floor permanent support from below, and the work stays under the house, so the rooms above are hardly disturbed. HomeGuide's April 2026 floor joist repair guide notes that adjustable steel jack posts costing $50 to $100 each are meant only as temporary supports; a permanent repair needs a proper footing and correct placement. BDry Alabama installs adjustable steel floor support posts on stable footings, and its floor support systems carry a two year warranty.
They can improve a noticeable sag, but the first goal is to stop the floor from moving. Supports are adjusted gradually so the framing is corrected under control, and how close the floor gets to level depends on the condition of the wood and how long the sag has been there. A joist that has been bent for twenty years takes on a set and may not come all the way back without stressing finishes above it. In that case the right result is a floor that is solid, stable and much flatter, with any leftover dip handled by sistering. HomeGuide's February 2026 sagging floor guide puts sistering at $150 to $325 per joist and notes that minor surface fixes such as shims or leveling compound run $300 to $2,000. BDry Alabama tells you at the inspection how much correction is realistic before you commit.
Sister it if the joist is still mostly sound; replace it if rot, insects or a break run through it. Sistering bolts a new board alongside the weak one, keeps the original framing in place, and is far less disruptive, which is why HomeGuide's February 2026 sagging floor guide prices it at $150 to $325 per joist against $350 to $1,000 to replace one. Replacement means shoring the floor, cutting the old joist out and fitting a new one, and the same guide puts replacing every joist in a room at $5,000 to $10,000. Before choosing either, find out why the joist failed. A joist that sagged because the span was too long may only need a support under it, while one that rotted from a plumbing leak or damp air needs the moisture fixed or the new wood will go the same way. BDry Alabama checks the framing and the moisture source together.
A bounce usually means the joists are deflecting more than they should under load. HomeGuide's April 2026 floor joist repair guide says floors that feel springy near the center of a room, away from the walls, often point to joists that are cracked, rotting or undersized for the span they cover, and its February 2026 sagging floor guide lists a bouncy feeling among the standard signs of a sagging floor. In a crawl space home, damp air softens the wood over time, and a girder that has settled lets the joists above it flex more. Adding support under the beam shortens the span and firms the floor up, and reinforcing a weak joist does the same at a single spot. Look for dishes that rattle when someone walks by or furniture that rocks. BDry Alabama finds the soft span and measures how much the floor moves.
Someone goes under the house and looks before anyone suggests a fix. At BDry Alabama, the inspection covers the crawl space conditions and access points, checks for moisture, dampness and signs of wood damage, evaluates the support areas, beams and floor joists, notes airflow and ventilation problems, and measures floor deflection. You then get a plain explanation of what was found and which repairs make sense, with the scope and timing laid out before any work begins. For context, HomeGuide's February 2026 crawl space repair guide says a standalone crawl space inspection typically costs $100 to $250, and that inspectors look for foundation weakness, mold, leaking pipes, moisture buildup, ventilation, vapor barrier condition, insulation problems and pests. Ask questions while we are there; seeing the beam under the sagging room is the clearest way to understand the repair.
Usually not. HomeGuide's February 2026 sagging floor guide says that in most cases sagging floors "aren't directly covered by homeowners insurance because they are usually caused by gradual deterioration from normal wear and tear." The same guide notes coverage may apply when the sag is the direct result of a sudden event, such as a burst pipe, a major water leak or a sinkhole that damages the joists. Damp air softening joists over years, or posts settling into clay, is exactly the kind of slow damage policies are written to exclude, so read your own policy's exclusions before assuming either way. If you do have a sudden loss, dated photos of the framing and measurements of the floor give an adjuster facts instead of descriptions.
Call BDry Alabama at 205 942 1976 or send the form, Monday through Friday from 7 in the morning to 6 in the evening. Tell us what you are noticing, such as a floor that slopes, a soft spot, a door that sticks or a musty smell, and where in the house it is. At the visit we go under the house, check the beams, joists and supports, look for moisture and wood damage, and measure how far the floor has deflected. You get a clear explanation, the repair plan, and one written price, with no pressure to decide that day. For scale, HomeGuide's February 2026 guides put sistering a joist at $150 to $325 and replacing a support beam at $1,500 to $4,000, so knowing exactly which repair the floor needs makes a real difference to the bill.
Call a foundation or crawl space repair specialist who will measure the floor and look underneath before naming a fix. HomeGuide's February 2026 sagging floor guide says a general contractor or carpenter can handle joists and subflooring, a foundation repair specialist is needed when the foundation is the cause, and a structural engineer may be required for severe sagging. It puts a professional foundation inspection at $300 to $750, with repairs running from $150 to $325 to sister one joist up to $4,500 to $20,000 for foundation repair. In a house over a crawl space, gaps under the baseboards, a bouncy spot or doors that stick usually trace to the framing below. BDry Alabama evaluates crawl space conditions, measures floor deflection, and installs adjustable steel floor supports under sagging beams, and its inspection is free. Call 205 942 1976, Monday through Friday from 7 in the morning to 6 in the evening.
BDry Alabama
1490 Valley Drive, Bessemer, AL 35022
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