Decision tool
Flooded Basement Cleanup: DIY or Call a Pro?
You can usually handle a flooded basement cleanup yourself if the water came from a clean source like a burst supply line, covers a small area less than about an inch deep, hasn't soaked drywall, carpet pad or insulation, and can be dried within 24–48 hours. Sewage, outside floodwater, water near electrical equipment, or large wet areas call for a water mitigation company.
Before you start
Stop first if any of these are true
- Water is touching outlets, cords, the panel or the furnace.
- You smell gas, or a wall is bulging or newly cracked.
- You'd have to stand in water to reach the power.
Shut power off only from a dry spot, or call an electrician. For a gas smell, leave and call the utility from outside.
Water still coming in? Make it safe and stop the source first: what to do in the first hour after a basement floods.
Decision tool
Can you clean this up yourself?
Eight questions. The verdict updates as you answer and lists the rules behind it.
Method
How the verdict is decided
The tool applies published rules in a fixed order and shows which ones fired. Nothing here depends on JavaScript.
| Rule | Source | Effect on the verdict |
|---|---|---|
| Water touching outlets, cords, the panel or furnace; gas smell; walls moving | CDC, Reentering Your Flooded Home | Stop: make it safe first, before any cleanup |
| Sewage, floor-drain backup, or outside floodwater (Category 3) | IICRC S500; EPA Mold Cleanup in Your Home | Call a pro |
| Washer, toilet (no feces), rain or groundwater seepage, sump overflow (Category 2) | IICRC S500 examples | Starts at DIY with caution |
| Clean water that has stood about 48 hours or more | IICRC S500 time and temperature rule (the 48 h figure is the 1999 edition's) | Treated as Category 2 |
| 1 inch or more standing, or more than ~100 sq ft wet | Common restoration threshold; drying-capacity arithmetic | Raise one step |
| Over 6 inches, or 1 inch or more over 500+ sq ft | Extraction arithmetic (vac 1–2 GPM) | Raise two steps |
| Wet drywall and insulation together (wet wall cavities) | EPA Table 1 | Call a pro |
| Wet drywall, insulation or ceiling tile | EPA Table 1 | At least DIY with caution |
| Wet more than 48 hours | EPA; CDC flood mold guidance | Assume mold; at least DIY with caution |
| Visible mold over about 10 sq ft | EPA, A Brief Guide to Mold | Call a pro |
| Asthma, immune compromise or an infant in the home, with Category 2/3 water or mold | CDC | Call a pro |
The starting point is the water category from the IICRC S500 standard, the restoration industry's reference for water damage. Category 1 starts at DIY, Category 2 at DIY with caution, Category 3 at call a pro. Size, wet materials, time and who lives in the house can only move the verdict up, never down. Safety checks sit outside the ladder: if anything electrical is wet, if you smell gas, or if a wall is moving, the tool says to make it safe before cleanup of any kind.
Materials follow EPA's Table 1 for water-damaged materials, which assumes drying starts within 24–48 hours. The mold thresholds are EPA's (about 10 sq ft) and CDC's (if it isn't dry in 24–48 hours, assume mold). Every ranking page for this question names these rules; none lets you apply them to your own basement, and almost all are written by companies that sell the “call a pro” answer. We don't do cleanup or take referral fees on this page.
Water damage categories
Category 1, 2 and 3 water, and why rain seepage isn't clean
| Category | Basement examples | What it changes |
|---|---|---|
| Category 1 (clean) | Burst supply line, water heater, clean-water pipe | Carpet can often be dried if you act within 24–48 h. Gloves and boots. |
| Category 2 (grey) | Washer or dishwasher discharge, toilet overflow without feces, sump overflow, groundwater or rain seepage | Pad, insulation and more drywall go. Add eye protection and an N95. |
| Category 3 (black) | Sewage, floor-drain backup, toilet with feces, outside floodwater | Porous materials are discarded. Professional cleanup with containment and PPE. |
Categories from the IICRC S500 Standard for Professional Water Damage Restoration. Water gets worse with time and warmth: clean water left standing about 48 hours is treated as Category 2.
If the water came up through a floor drain or toilet, it is sewage. What to throw out, how to disinfect and who cleans it are covered in sewage backup cleanup.
How to clean up a flooded basement
How to clean up a flooded basement, in six steps
- Make it safe. Power off from a dry spot, no gas smell, no generators indoors.
- Photograph everything before you move it, for the insurer.
- Remove the water: pump first if it's deep, then a wet/dry vac.
- Pull out what can't be saved: pad, wet insulation, ceiling tile, swollen drywall.
- Clean hard surfaces with water and detergent. Never mix bleach with ammonia.
- Dry it within 24–48 hours with a dehumidifier and fans, and check with a moisture meter.
The timed version, with what to do in each window, is our guide to what to do in the first hour after a basement floods.
DIY workload
What you're signing up for if you DIY
| Water | Gallons | Wet/dry vac | Tank dumps | Spare sump pump |
|---|---|---|---|---|
| 1 in over 100 sq ft | 62 gal | 30 min–1 h | 11 | 1 min–1 min |
| 1 in over 300 sq ft | 187 gal | 1.6 h–3.1 h | 32 | 6 min–6 min |
| 1 in over 600 sq ft | 374 gal | 3.1 h–6.2 h | 63 | 12 min–12 min |
| 1 in over 1,000 sq ft | 623 gal | 5.2 h–10.4 h | 104 | 18 min–24 min |
| 3 in over 600 sq ft | 1,121 gal | 9.3 h–18.7 h | 187 | 30 min–42 min |
1 inch over 1 sq ft is 0.623 gallons. Wet/dry vac at a realistic 1–2 GPM including carrying and dumping; dumps assume a 12-gallon tank emptied at half full (about 50 lb). Spare 1/3 HP sump pump at about 25–35 GPM. Extraction only: drying comes after.
- Equipment: a submersible pump for anything over about an inch, a wet/dry vac for the last of it, a dehumidifier (see how big a dehumidifier the space needs), two or three fans, and a pin moisture meter. All on GFCI outlets reached from dry floor.
- Protection: rubber boots and gloves for any category; add goggles and an N95 for Category 2 or any mold.
- The 48-hour check: if drywall, framing or carpet still reads wet two days in, treat it as moldy and remove it, or hand the job off.
Calling a pro
What a water mitigation company does that you can't
A mitigation crew maps moisture with meters and thermal cameras to find water inside walls and under flooring, then dries with low-grain refrigerant (LGR) dehumidifiers and high-velocity air movers that pull far more water than household units. They apply antimicrobials, contain Category 3 work, and document readings each day, which is the record an adjuster wants. Ask them about whether insurance covers the cleanup before work starts, and compare their estimate with our flood cleanup cost planning ranges.
Limits
What this tool does not tell you
It is a decision aid, not an inspection. It can't test the water for contamination, see moisture or mold inside walls, judge whether a wall has been damaged, or read your insurance policy. If you're unsure where the water came from, find where the water got in before you rebuild anything.
Written by the Wet Basement Fixes editorial team, reviewed against the IICRC, EPA and CDC sources below under our editorial policy. Last reviewed: October 18, 2026.
Related pages
Where to go next
Basement flooded? What to do in the first hour
Safety, the shot list for insurance, and the 48-hour drying clock.
Read nextDoes homeowners insurance cover a flooded basement?
Coverage by cause, and what flood insurance pays in a basement.
Read nextBasement flooding
Why basements flood and how to stop a repeat.
Read nextDehumidifier size calculator
Pints per day for drying out the space.
Read nextWet basement repair cost calculator
Planning ranges for cleanup and the fix that follows.
Read nextFAQs
Flooded basement cleanup: common questions
Can I clean up a flooded basement myself?
Often, yes, when the water is clean (a burst supply line or water heater), less than about an inch deep, covers less than about 100 sq ft, hasn't soaked drywall or insulation, and can be dried within 24–48 hours. Sewage, outside floodwater, wet wall cavities, or water near anything electrical change that answer.
When should I call a water mitigation company?
Call one for sewage or a floor-drain backup, outside floodwater, more than about 100 sq ft wet or an inch or more across the floor, wet insulation behind drywall, visible mold over about 10 sq ft, or if someone in the home has asthma, a weakened immune system, or is an infant.
Is rainwater in the basement Category 1 water?
Usually not. Rain or groundwater that has seeped through soil and concrete is generally treated as Category 2 under the IICRC S500 standard's examples, and any water that stands for about 48 hours gets worse. Treat it as grey water: gloves, boots, eye protection, and discard the carpet pad.
How long does it take mold to grow after a basement flood?
EPA advises drying water-damaged materials within 24–48 hours to prevent mold growth, and CDC says to assume mold if things can't be dried in that window. Visible growth can take days to a couple of weeks to show, so a basement that looks fine on day three may not be.
What do I do with wet carpet in the basement?
If the water was clean and you can start within 24–48 hours, extract it with a wet vacuum, pull up and discard the pad, and dry the carpet and the slab with a dehumidifier and fans. After grey water, sewage or a longer soak, carpet and pad are usually discarded. Photograph them first.
Will insurance still pay if I do the cleanup myself?
Often, for a covered cause. Most policies expect you to prevent further damage, so drying it yourself is usually fine. Photograph everything first, keep a cut sample of the carpet and pad, keep receipts, and ask the insurer before throwing large items away. This is general information, not coverage advice.
Sources
Sources
- IICRC — S500 Standard for Professional Water Damage Restoration (water categories)
- Cleanfax — Practical application: S500-2015 key terms (category examples; time and temperature)
- EPA — A Brief Guide to Mold, Moisture and Your Home (24–48 hours; about 10 sq ft)
- EPA — Mold Remediation in Schools and Commercial Buildings, Chapter 4, Table 1 (water-damaged materials)
- EPA — Mold Cleanup in Your Home (sewage and contaminated water)
- CDC — Reentering Your Flooded Home (power, gas, generators)
- CDC — Tips on cleaning mold after a flood (24–48 hours; who should stay out)
- Ready.gov (FEMA) — Floods: after a flood
Thresholds are drawn from the sources below and applied as general rules. They are not a substitute for an on-site assessment.