The essentials in 30 seconds
Make the home safe first: power off from a dry spot, gas off if you smell it, and an inspection before you enter a structurally damaged house. Then decide what kind of water you have. Clean water from a supply pipe or rain can often be dried in place; gray water from a washing machine or dishwasher means the carpet pad goes; black water, meaning sewage or floodwater from rivers or the sea, means porous materials such as carpet, pad and soaked drywall are thrown away. Start drying within 24 hours: EPA warns that mold can grow on materials left wet for more than a day, and its cleanup tables are built around a 24 to 48 hour window. Photograph everything, including the water line on the walls, before you throw anything out.
- Children and pregnant people should stay out of flood cleanup work.
- Wear an N-95 respirator, goggles, rubber gloves and boots around floodwater.
Water damage: what to do in the first 24 hours
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01
Stop the water
For a burst pipe or appliance hose, close the fixture valve or the main water shut-off. For a leak from above, see our guide to a ceiling leak.
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02
Make the electrics safe
Follow the safety box above. Unplug appliances only once you are standing somewhere dry.
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03
Air the house
After several days closed up, open doors and windows and let the house air for at least 30 minutes before staying inside; CDC advises assuming mold is present.
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04
Photograph before you touch
Take photos and video of every room from several angles, the water line inside and outside, and damaged belongings, before cleanup starts.
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05
Call your insurer
Report the loss as soon as you can; the documentation section below lists what to keep.
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06
Remove standing water
Use a wet-dry vacuum, a transfer pump or a sump pump once an electrician has confirmed the power is safe.
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07
Pull out what is soaked
Rugs, cushions, boxes and anything that holds water. Move salvageable items to a dry room.
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08
Start drying
Open windows when the outside air is drier, and run fans and a dehumidifier. CDC suggests setting fans at a window or door so they blow air outwards.
Clean, gray and black water: why the source changes everything
What you can keep depends on how dirty the water was. Restoration professionals sort water into three categories, and North Carolina State Extension uses the same split for carpets.
| Category | Typical sources | What it means |
|---|---|---|
| Clean water | Burst supply pipe, tub or sink overflow with clean water, rainwater | Most materials can be dried if you act within 24 to 48 hours |
| Gray water | Washing machine or dishwasher discharge, broken aquarium, punctured waterbed | Unsanitary: carpet pad is thrown away, carpet needs professional cleaning with a biocide |
| Black water | Sewage backup, floodwater from rivers, streams or the sea | Grossly contaminated: soaked carpet, pad, drywall and other porous items are discarded |
Two details matter. Gray water left untreated for more than 48 hours can turn into black water. And EPA's drying guidance covers clean water only: with sewage or floodwater, it advises keeping fans off until the water is confirmed clean, and calling an experienced professional.
Floodwater can carry human and livestock waste, household chemicals and sharp debris. If you have to work in it:
- Wear rubber boots, rubber gloves and goggles, and wash your hands with soap and clean water afterwards.
- Cover any cut with a waterproof dressing. See a doctor if a wound becomes red, swollen or oozing; after a puncture or a dirty wound, a health professional can tell you whether you need a tetanus booster.
- Keep children away from the water and from toys it has touched.
- Wash clothes worn during cleanup in hot water with detergent.
What to tear out and what to save
Drywall and the flood cut
Drywall (plasterboard) soaks water up like a sponge. For clean water, EPA says it can be dried in place if there is no obvious swelling and the seams are intact; otherwise it comes out. After a flood, the FEMA and Red Cross manual is direct: if water soaked the wallboard four feet or more above the floor, replace all of it; if the water was lower, remove the bottom four feet, which lets you refit standard 4 × 8 foot sheets laid sideways. This horizontal cut is what restorers call a flood cut.
To check for water trapped in a wall, remove the baseboard and push an awl in about 2 inches above the floor; if water drips out, open a drainage hole with a hand tool or cordless drill, clear of the wiring at outlet height.
Insulation
- Fiberglass batts: throw away if muddy. If soaked by clean water they can be dried, but slowly, so most people replace them.
- Cellulose (blown-in paper): replace; it holds water and can lose its fire-retardant treatment.
- Rigid plastic foam board: often survives and may only need hosing off.
Floors, wood and furniture
| Item | Clean water, dried within 24–48 hours | Flood or sewage water |
|---|---|---|
| Wall-to-wall carpet | Can often be dried in place | Discard; cut into strips to carry out |
| Carpet pad | Can be restored if wet less than 48 hours | Discard |
| Vinyl or linoleum | Clean and dry; lift if loose, warped or foam-backed | Lift and dry the subfloor |
| Wood studs and joists | Dry with fans and dehumidifiers | Clean and dry; they can usually stay |
| Upholstered furniture | Extract water and dry; hard to finish in 48 hours | Usually discard |
| Mattresses, pillows, foam | Often discarded | Discard |
| Food, cosmetics, medicines, stuffed toys | Discard if touched by the water | Always discard |
Flooded wood can reach about 30 % moisture content and swell, but studs and sills usually return to shape if they dry naturally. Keep a sample of every carpet or floor covering you throw away for the adjuster.
Drying out: how long it takes and how to know it is done
Plan for several days to several weeks, and keep air moving after surfaces look dry: wall cavities and subfloors dry last.
- Fans and dehumidifiers do most of the work; close the room you are drying.
- Mold first, then fans. If you can already see mold, clean it gently with detergent and water before you run fans, so they do not spread spores.
- The HVAC system: if any part was under water, keep it off and have it cleaned by a professional experienced in mold before you use it. Running a contaminated system spreads mold through the house.
- Measure, do not guess. EPA suggests a moisture meter: wood and other materials should read 15 % or less before you refinish.
- Check a concrete slab by taping clear plastic sheeting to it for about 16 hours. Moisture under the plastic means it is too wet for new flooring.
- Close up last. Leave wall cavities open and skip paint and sealers until the materials are dry inside.
How fast mold grows after water damage
| Time wet | What to expect | Action |
|---|---|---|
| First 24 hours | Mold can begin on wet wood, drywall, carpet and furniture | Remove water and start drying at once |
| 24 to 48 hours | EPA's window to dry materials before mold sets in | Discard what cannot be dried in time |
| After 48 hours | Treat soaked porous materials as moldy | Follow mold cleanup guidance; ask a professional for large areas |
| Weeks later | Musty smell or spots behind baseboards or under flooring | Open up and inspect; the moisture is still there |
People with asthma, other lung conditions or a weakened immune system should stay out of moldy areas. Wear an N-95 respirator, goggles without vent holes, gloves, long sleeves and boots, and in older homes check for asbestos and lead before you cut into walls or floors.
For cleaning, CDC advises washing hard surfaces with soap and water, then disinfecting with a mixture of 1 cup of household bleach to 1 gallon of water. Never mix bleach with ammonia or any other cleaner. Moldy areas larger than about 10 square feet call for a professional; our guide to mold remediation covers the details.
Documenting water damage for your insurance claim
Homeowners policies usually cover sudden damage such as a burst pipe; surface flooding needs a separate flood policy, and some policies add cover for sewer backup or sump pump failure. FEMA's checklist for flood claims is a good model for any claim:
- Report quickly. Your insurer should assign an adjuster to contact you within 48 hours of your report.
- Photograph and film the outside and inside from several angles, including the water line inside and outside.
- Record make, model and serial number of appliances and electronics.
- List every damaged item with its description, age, quantity and replacement value.
- Hold on to evidence. Keep everything until the adjuster has seen it, except health hazards; keep samples of carpet, flooring and blinds you must throw away.
- Keep receipts for fans, dehumidifier rental, materials and emergency repairs.
- Watch the deadline. NFIP policyholders must send their documentation within 60 days of the flood unless the insurer sets another timeframe.
When to call a water damage restoration company
Call a professional when the water was gray or black, when walls are soaked inside, when mold covers more than about 10 square feet, when the HVAC system was flooded, or when drying cannot start within a day. Restoration firms bring large fans and dehumidifiers that can dry a house in a few days.
Questions to ask before you sign:
- What category of water do you think this is, and what will you remove because of it?
- How will you measure moisture, and what readings will you reach before closing up walls?
- Do you follow a recognized standard, such as EPA mold guidance or the IICRC standards, and will you show me your references?
- Can you show proof of insurance, including workers' compensation, so you are not liable for accidents on site?
- Can I have a written estimate and a complete contract, with any guarantee in writing?
After a disaster, be wary of firms that inflate prices or of out-of-town crews that ask for payment in advance. Try licensed local companies first, check their reputation and talk to more than one before you sign.
Water damage: frequently asked questions
What should I do first after water damage?
Make the home safe: power off from a dry spot, gas off if you smell it, and stop the water at the valve. Then photograph everything and start removing water and drying.
How long do I have before mold grows after water damage?
Mold can begin on wet materials within 24 hours. Aim to dry everything within 24 to 48 hours.
Can I dry wet drywall or does it need replacing?
After a clean-water leak, drywall can stay if it has kept its shape and the seams are intact. After a flood, remove it to at least four feet up, or all of it if the water rose higher.
What is the difference between gray water and black water?
Gray water is unsanitary waste water from appliances such as washing machines. Black water contains sewage or floodwater from rivers or the sea, and soaked porous materials must be thrown away.
Can wet carpet be saved?
Carpet soaked by clean water and dried within 24 to 48 hours can often be saved. After gray water the pad goes; after black water both carpet and pad go.
How long does it take to dry out a house after water damage?
Usually several days to several weeks. Use a moisture meter and wait for readings of 15 % or less before you refinish.
Does homeowners insurance cover water damage?
It usually covers sudden events such as a burst pipe. Damage from outside flooding generally needs a separate flood policy.
Sources
Official guidance, checked on 27 October 2026.
- US EPA · Flood cleanup to protect indoor air and your health ↗Mold after 24 hours, protective equipment, who should avoid cleanup, generators at 20 feet, drying time, 15 % moisture reading, slab plastic test, HVAC.
- US EPA · Mold remediation guide, Table 1: water damage cleanup ↗What to do with drywall, insulation, carpet, wood and furniture within 24 to 48 hours; clean water only; fans and contaminated water.
- CDC · Reentering your flooded home ↗Building inspection, gas, electricity, airing for 30 minutes, removing water, fans facing out, HVAC.
- CDC · Floodwater after a disaster or emergency ↗What floodwater carries, protective gear, wounds and tetanus, discarding items, bleach solution.
- FEMA and American Red Cross · Repairing your flooded home ↗Pumping a basement in stages, four-foot flood cut, insulation types, wood moisture, carpet, items to discard, insurance types, choosing a contractor.
- NC State Extension · Water-damaged carpets and rugs ↗Clean, gray and black water, carpet and pad by category, gray water turning black after 48 hours.
- FEMA FloodSmart · NFIP claims checklist for policyholders ↗Reporting, adjuster within 48 hours, photos, water lines, serial numbers, samples, 60-day deadline.
Water on the floor right now?
Make the power safe, stop the water, and take photos of every room before you start moving things.