Water damage restoration in Houston
FEMA rates Harris County Very High for hurricane risk on top of its flooding ratings. Whatever brought the water, the drying window EPA publishes is 24 to 48 hours.
What usually causes it in Houston
- Barely freezes: 9.7 nights a year. If a pipe let go, cold was almost certainly not why.
- Water from outside is a real route here — FEMA rates Harris County for hurricane and coastal flooding, so CDC's floodwater rules apply if that is what came in.
The figures behind this, with sources
- Inland flood risk
- Very High
- Coastal flood risk
- Relatively High
- Hurricane risk
- Very High
- Flood events a year, county-wide
- 5.1
- Expected flood damage to buildings, county-wide, a year
- $1.09B
- Nights below freezing, a year
- 9.7
- Yearly rainfall
- 49.77"
- Homes built before 1980
- 29.3%
- Rented homes
- 58%
FEMA National Risk Index, county level · NOAA NCEI, 1991–2020 U.S. Climate Normals · U.S. Census Bureau, ACS 5-year 2019–2023, tables B25034 and B25003. County-level ratings describe the county, not your address.
What the record says about Houston
Houston is one of the few places where all three routes are live at once: a pipe inside, a storm outside, and a hurricane season that brings both. FEMA rates Harris County Very High for hurricane risk and Relatively High for coastal flooding on top of its inland rating.
That matters for one practical reason. If the water came from outside, CDC's position is to stay out of it — it can carry sewage and hazardous waste, and the cleanup is a different job from drying. Establishing which kind of water it was is the first thing anyone should ask you.
Freezing is rare, about 9.7 nights a year, but Texas winter storms have shown what happens when plumbing built for this climate meets one that is not. If a line let go in February, cold is a plausible cause here even though the annual average says otherwise.
Figures from FEMA National Risk Index and NOAA NCEI 1991–2020 Climate Normals, checked 2026-10-16. County-level ratings describe the county, not your address.
The first 48 hours in Houston
The hours come from EPA and CDC, and they do not change with the weather.
- 0–2 h
Safety first, then the source
- If there is standing water and the main power switch is reachable from a dry spot, CDC says to turn the power off. If you would have to step into the water to reach it, call an electrician instead.
- 2–24 h
Water out, air moving
- CDC: clean up and dry out the building fully and quickly, within 24 to 48 hours of the flood.
- 24–48 h
The window is still open
- EPA: if wet or damp materials or areas are dried 24 to 48 hours after a leak or spill happens, in most cases mold will not grow.
- 48+ h
A different job now
- Past this point the question changes from drying to what has already grown.
- EPA puts the line at about 10 square feet: under roughly a 3 ft by 3 ft patch, in most cases a homeowner can handle the job; above it, the guidance is different.
Houston questions
Is flood water here treated differently from a burst pipe?
Yes, and the difference is about contamination rather than volume. CDC says nobody knows exactly what is in floodwater at any given point in time, that it can carry human and livestock waste, hazardous waste and coal ash containing arsenic, chromium and mercury, and that its guidance is to stay out of the water. A clean supply line is a drying job; water that came in from outside is a cleanup job as well.
My house has flooded before. Does that change the work?
It changes what gets checked. Material that has been wet before and dried slowly is where problems tend to recur, and anyone quoting the work should be looking behind and under it rather than only at what is visible now.
How fast does it have to happen in this climate?
The published window does not change with the weather: EPA says material dried within 24 to 48 hours of a leak will, in most cases, not grow mold. Humidity makes hitting that window harder, not later.
Does homeowner's insurance cover this?
Flooding from outside and a burst pipe inside are usually handled by different policies, and the answer depends on yours rather than on the damage. The general position is set out on our insurance page, which links to the Insurance Information Institute rather than promising you anything.
Where this comes from
- EPA — A Brief Guide to Mold, Moisture and Your Home — Where the 24 to 48 hour drying window and the 10-square-foot rule of thumb come from.
- CDC — About Mold — Federal guidance to clean up and dry out fully within 24 to 48 hours of a flood.
- CDC — Safety Guidelines: Floodwater — What floodwater can carry, and why the advice is to stay out of it.
- CDC — Safety Guidelines: Reentering Your Flooded Home — Power, gas and when not to go back inside.
- FEMA — National Risk Index — County-level flood, hurricane and riverine risk used on the city pages.