How to Tell if Water Damage Is Old or New

First question: Is it still wet?

Before you worry about how old a stain is, find out if water is still getting in. That’s what decides how fast you need to act.

1. 1

   Do a quick touch test

   First, make sure the stain isn’t near a light fixture, outlet, or wiring, and the ceiling isn’t sagging. If it is, skip this and see “Stay safe” below. Otherwise, gently press the edge of the stain with a dry hand. Damp or soft drywall means it’s wet now. A spot that feels noticeably cooler than the drywall around it may be wet too. Dry and firm usually means no water is coming in right now. But a leak that only happens during rain or a shower can still be dry between times.

2. 2

   Run the water above it

   If the stain is dry and there’s a bathroom, kitchen, or laundry room above it, use it: run the shower, fill and drain the tub, flush the toilet. Then check the stain again over the next day. If the stain is already wet, skip this step. You already know water is getting in. Home inspector Reuben Saltzman of Structure Tech says that when a stain under a plumbing fixture is dry, the fixture above should be tested and then the stain checked again.

3. 3

   Check after the next rain

   If the stain is on a top-floor ceiling or near an outside wall, look at it again during or after the next storm. A stain that darkens or spreads after rain points to the roof, flashing, or windows.

Clues that point to old or new water damage

These signs can help you make a good guess. None of them is proof on its own, so look at them together.

Why mold matters: the EPA says to dry water-damaged areas and items within 24 to 48 hours to prevent mold growth. If you see mold, the area has likely stayed damp longer than that. The EPA also says you may suspect hidden mold if a room smells moldy but you can’t see the source.

How to track a stain over the next few days

If you’re not sure whether the leak is still going, watch the stain for a few days. It’s free and takes a minute a day.

• Trace the edge of the stain lightly with a pencil and write the date and time next to it.
• Take a photo from the same spot each day, with a phone that saves the date.
• Note what happened before each check: rain, showers, laundry, the dishwasher.
• If the stain grows past your pencil line, the leak is active. Don’t wait to call someone.
• If it stays dry and inside the line for a week or more, including after rain and normal water use, the leak has likely stopped. If it hasn’t rained yet, keep checking after the next storm. Still find out what caused it.

A pro can tell you more. InterNACHI, a home inspector association, says a moisture meter is especially useful for telling whether the source of a wall or ceiling stain is active or has been repaired. Keep in mind that a meter shows whether something is wet right now. It can’t tell you exactly when the water got there.

Why the age matters for insurance

This is often the real worry. Most homeowners policies are written for sudden accidents, not slow leaks. Washington State’s insurance commissioner, the regulator in our neighboring state, says most homeowners policies don’t cover gradual leaks, and that insurers generally treat them as maintenance problems. Its list of gradual leaks that insurers usually don’t cover includes “damage that develops over more than a couple of days.” The same page says sudden leaks are usually covered if you report them to your insurer quickly.

The NAIC explains that homeowners policies generally cover damage from a sudden and accidental discharge of water from a plumbing system. Your own policy has the final word.

Good records help. In one case reviewed by the UK Financial Ombudsman Service, an insurer turned down a ceiling stain claim as gradual damage. The homeowner had taken photos the day she made the claim, showing a stain that hadn’t spread far and had no mold. The ombudsman said her photos proved the stain was new. It also found she couldn’t have known about the hidden leak until the stain appeared, and that she reported it quickly. It told the insurer to accept her claim. That case is from the UK, and US policies and rules differ, but the lesson still applies: photograph it the day you find it, and report it promptly.

The Idaho Department of Insurance has tips for filing a home claim. Our guide to water damage insurance claims in Idaho walks through the steps, and our guide to a denied water damage claim covers what to do if they say no.

Found an old stain in a home you’re buying or renting?

A stain in a house you’re about to buy raises different questions: what caused it, and was it fixed?

• Ask the seller. Idaho’s seller disclosure form asks about problems with basement water, roof condition and age, plumbing, and drainage, based on what the seller knows.
• Ask your home inspector to check the stain with a moisture meter and to look at the plumbing, roof, or attic above it.
• Ask for repair records, like a plumber’s or roofer’s invoice that shows what was fixed and when.
• If you rent, tell your landlord or property manager in writing, with photos and the date you noticed it.

Who to call

A plumber or roofer fixes what leaked. A restoration crew handles the damage to your home: finding hidden water, drying it out, and removing materials that can’t be saved. You can ask to see their moisture readings.

Frequently asked questions