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Gainesville Foundation

Serving Gainesville and nearby areas

Crawl Space Moisture in Gainesville, FL

Crawl space moisture in older Gainesville homes slowly rots the wood that holds up your floor, and a free inspection shows how wet it is and what it takes to dry it out.

Call now: (352) 724-7728 or book your free inspection online

Book a free foundation inspection

Tell us what you are seeing. A local specialist calls you back the same business day.

Why houses move in Gainesville

Much of Gainesville sits on about five feet of sand over clay-rich soil, with limestone below that water slowly dissolves. Heavy summer storms soak the sand and wash it down into gaps in the rock. That is why the county sees sinkholes and settling under both old homes near downtown and newer slab homes on the west side.

  • Half the year is muggy

    Gainesville stays muggy from about May 4 to October 31, according to WeatherSpark, and August averages more than 30 muggy days. That damp air settles into the cool space under a raised floor.

  • Water a few feet down

    USDA surveys of common Alachua County soils show the water table rising to about 4 or 5 feet below the surface for months at a time, and closer in some years. Damp ground under a crawl space gives off moisture all season.

  • Old raised homes

    Gainesville's historic districts, including Pleasant Street and the Duckpond area, hold wood frame homes from the late 1800s and early 1900s. Many of these sit on piers over a crawl space.

What it costs

Typical published ranges for Gainesville. The contractor's written estimate is the price, and the inspection is free.

WorkTypical range
Crawl space inspection and written estimate Free
Crawl space encapsulationThis Old House, average about $5,500 $1,500 to $15,000
Dehumidifier with wiringThis Old House $800 to $2,000
Drainage for the crawl spaceThis Old House $600 to $1,800
Mold removalThis Old House $500 to $4,000
Sistering a rotted joistFixr $150 to $325per joist

See typical foundation repair prices in Gainesville

What you will notice

Crawl space trouble starts out of sight. You notice it from the rooms above, or the first time you open the access door.

A musty smell

In the house, worse on humid days or when the AC first runs.

Soft or bouncy floors

Most of all near bathrooms, the kitchen or outside walls.

Floors that slope

Or dip in the middle of a room.

Cupped wood floors

Where the boards curl up at the edges.

Damp or dark soil

Under the house, or standing water after a storm.

White or black spots

On joists, beams or the underside of the floor.

Sweating pipes

Or ducts dripping onto the ground.

Fallen insulation

Hanging down from between the joists.

Bugs

Like termites, roaches or silverfish showing up more often.

Why crawl spaces get wet here

Older homes in Gainesville were often built up off the ground on piers. You see them near downtown and the University, in places like Pleasant Street and the Duckpond area. A raised floor kept a house cooler before air conditioning. It still works. But the space under it fights the local weather every summer.

Three things keep it damp.

The air. Gainesville stays muggy for about six months, from early May to the end of October. August averages more than 30 muggy days. When that warm, wet air drifts into the shade under the house, it hits cool pipes, ducts and wood. Water forms on them, like on a cold glass.

The ground. USDA soil surveys show the water table in common local soils rises to about 4 or 5 feet down for months at a time. Bare dirt over damp ground gives off water vapor all season long.

The rain. Gainesville gets about 48 inches of rain in a normal year. Gutters that overflow and yards that slope toward the house send that water under the floor.

What the damp does over time

Moisture is slow. It takes years. But it works on every piece of wood under your floor.

Shims crush

The thin wood wedges on top of the piers rot and squash. The floor drops a little at each one.

Joists rot

Rotted joists sag and feel bouncy.

Sills rot

The board where the house sits on its piers softens at the ends.

Mold grows

The EPA says mold needs moisture, and keeping humidity below 60 percent helps stop it.

Pests move in

Damp wood draws termites and other bugs.

That is why moisture under the house usually turns into a floor problem in the end. See pier and beam repair.

Cosmetic or urgent?

Keep an eye on it

  • A faint musty smell only on the most humid days.
  • Damp soil but dry wood and no mold.

Get it checked soon

  • Standing water under the house after rain.
  • Wood that is dark, soft or crumbles when poked with a screwdriver.
  • Mold you can see on joists or the floor above.
  • A floor that feels soft or has started to sag.
  • A musty smell that is in the house all the time.

What the fix usually is

Most fixes start with keeping water out, then drying the air, then fixing any wood that already rotted.

Outside water

Gutters, downspout pipes and grading that sends rain away from the house. See drainage correction.

A ground cover

A plastic liner over the dirt to stop vapor from the soil.

Encapsulation

A heavier liner up the walls, sealed vents and a dehumidifier. This Old House puts the average at about $5,500, with most jobs between $1,500 and $15,000.

Dehumidifier

About $800 to $2,000 installed with wiring, per This Old House.

Wood repair

New shims, new posts and sistered joists. Fixr puts sistering at about $150 to $325 per joist.

Ask what humidity level the system is meant to hold, and how you can check it later.

What to do before the inspection

  1. Put a cheap humidity meter in the crawl space for a few days and write down the readings.
  2. Take photos through the access door with a flashlight.
  3. Note which rooms feel soft or smell musty.
  4. Clean out gutters and point downspouts away from the house.
  5. Do not crawl under the house if there is standing water, wiring on the ground or heavy mold.

Free crawl space check

Call (352) 724-7728 or send the short form. A local crew will go under the house, check the moisture and the wood, and give you a written plan and price.

Frequently asked questions

Is some moisture in a crawl space normal in Gainesville?

Some damp is hard to avoid in a city that stays muggy half the year. Standing water, wet wood, mold on joists or a musty smell inside the house are not normal and are worth a look.

Should I close my crawl space vents?

Not on your own. Vents let damp air out, but in muggy months they can also let wet air in. Sealing a crawl space works only with a liner and a way to dry the air, like a dehumidifier. Ask the inspector what fits your house.

What humidity should a crawl space have?

The EPA says to keep indoor humidity below 60 percent, and ideally 30 to 50 percent, to keep mold from growing. A cheap humidity meter left in the crawl space for a few days will tell you where you stand.

Can crawl space moisture make my floors soft?

Yes. Damp wood rots over time. Rotted shims crush and rotted joists sag. The floor above starts to feel bouncy or slope.

How much does crawl space encapsulation cost?

This Old House puts the average at about $5,500, with most jobs between $1,500 and $15,000. Size, how wet it is and whether wood needs repair all change the price.

Other services

Common foundation repair problems in Gainesville

Areas we serve around Gainesville

(352) 724-7728 Free inspection