Attention Property Managers. ask about our new client portal

Summer Flooding and Mold Risks for NY and NJ Homes

Summer Flooding and Mold Risks for NY and NJ Homes

As all Native New Yorkers know, when storm clouds arrive over their neighborhood, they hit fast. The weather is hot and humid, and suddenly, heavy rain is falling and streets are filling with water.

Residents of  New York and New Jersey saw this firsthand during the recent flash floods. On Monday, July 6, 2026. Flash flooding was reported in Coney Island and North Babylon, with flooding also affecting Long Island communities. Nassau County, Suffolk County, the Town of Southampton and in the Town of Hempstead they  declared states of emergency.  Roads flooded, water entered basements  and drainage systems couldn’t  keep up with the amount of rain.

The thing is that when floodwater enters a home, you might think it ends when the water goes down. That’s it, nothing to worry about. In fact, nothing is further from the truth.

What really happens when floodwater gets under floors is it soaks into insulation, and it creates a lot of moisture in basement walls and flooring. Then when the sun shines again and the heat returns, the trapped moisture beneath the surface causes mold to grow.

Why Does Summer Flooding Happen in New York and New Jersey?

Summer flooding is a real problem throughout New York and New Jersey. It’s always a sight to see those sheets of rain against the window, but heavy thunderstorms bring down a lot of water—too much for drains to handle—and they eventually overflow, the result being that the water has nowhere to go.

Summer Flooding Leads to Mold Growth

Summer creates serious mold problems after a flood because the weather is already humid.

Mold needs moisture to grow. After flood damage there is no shortage of moisture.

You might think that you can just  mop the floor and remove visible water, but that does not mean the home is dry.

The water will travel under flooring, and it soaks into the bottom of drywall. It enters wall cavities, and then the wood framing holds moisture; material such as wood stays wet even after the surface dries.

Summer Flooding Leads to Mold Growth
Summer Flooding and Mold Risks for NY and NJ Homes 4

Our experts at Exit Mold tell us that hidden moisture is one of the biggest problems after summer flooding. You may think that the water is gone, so that’s that. This false sense of security doesn’t last long before the musty smell starts.

Mold begins growing in hidden areas and quickly spreads before it can be seen.

The summer heat actually speeds  up the problem. Your closed walls and wet building materials will hold the moisture, and the  high outdoor humidity we get in New York and New Jersey during the summer makes drying harder.

This is why flood damage needs to be addressed immediately.

How Quickly Does Mold Grow After a Flood?

Mold begins growing within 24 to 48 hours after water damage.

All materials, such as drywall or insulation, carpeting, and wood, absorb water quickly. If these materials stay wet, mold will grow. It’s just a matter of time.

Waiting several days to see what happens gives moisture more time to spread through the home. Therefore, it is very important to hire a flood cleanup service to properly deal with the issue.

What Are Common Signs of Mold After Summer Flooding

If your home recently experienced flash flooding, even though the water has gone, if you notice the following signs, it shows that you have a mold issue:

  • Musty odors
  • Water stains on walls
  • Bubbling and peeling paint
  • Warped hardwood floors
  • Wet drywall
  • Damp basement air
  • Condensation
  • Visible mold growth
  • Dark spots on wood or insulation
  • Indoor allergy symptoms

A musty smell after flooding is an obvious sign that mold has already started growing.

High Risk Areas After a Summer Flood

A common misconception is that floodwater stays in one place. In reality, it moves through building materials and reaches places that are hard to inspect.

These are some of the first areas that our experts at Exit Mold  will  check after flood damage for mold.

Basements

Basements have the highest chance of getting flooded first by summer floods. I personally saw, this July, many flooded basements in NJ because of the floods.

Groundwater and failed sump pumps during heavy storm runoff all bring water inside. And what happens is that the basement walls and floors hold the moisture even after the standing water is removed.

Crawlspaces

Crawlspaces already have limited airflow. Floodwater makes the problem worse.

Wet wood and insulation become  a constant source of moisture under the house. Mold grows throughout the crawlspace and affects the air inside the house.

Drywall and Wall Cavities

Drywall absorbs water from the bottom up. Moisture remains inside the wall cavity. Mold then grows far behind the drywall where the homeowner will not see it.

Flooring

There are many types of flooring, but they are all susceptible to mold, just in different ways.

The water will sit underneath the flooring for days. Hardwood warps and mold grows on the subfloor. Carpet and padding will become smelly and develop mold patches in green and black.

What to Do After a Flash Flood
Summer Flooding and Mold Risks for NY and NJ Homes 5

What to Do After a Flash Flood

Always remember safety; do not enter standing water if you think there is a risk of electrical contact. Please stay away from contaminated floodwater and make sure you follow local emergency instructions.

Once it is safe to enter the property, remove standing water. Start with removing wet belongings out of the affected area. Then start ventilation and drying.

The next most important thing to do is call a flood damage and mold professional, because they will have the skills and the right tools to help you keep the mold out.

Above all, do not assume the home is dry because the floor looks clean.

Professional moisture testing will find water behind walls, and  deep inside your flooring materials.Above all, do not assume the home is dry because the floor looks clean.

Why Professional Flood Cleanup Matters

We see the same problem after major summer storms.

A homeowner cleans up the visible water. Fans run for a few days. The basement looks better. These steps are the first actions to take after a flood, in order to minimize the damage.

But a few weeks on and gradually your home starts to smell musty. Mold has already started growing behind walls and in the basement.

Professional flood damage cleanup focuses on the moisture you cannot see.

At Exit Mold , we inspect the affected areas and identify where water has traveled. We use moisture testing to find hidden wet areas and determine which materials have been affected.

Proper flood cleanup and mold remediation  includes:

  • Moisture testing
  • Water damage inspection
  • Removal of damaged materials
  • Drying and dehumidification
  • Mold inspection
  • Mold remediation
  • Treatment of affected areas
  • Steps to prevent recurring mold growth
  • The goal is not to make the floor look dry.

Don’t Wait For The Mold

The biggest mistake you as a homeowner can make after a flood is to wait for visible mold.

As we have pointed out again and again in this blog, mold starts in invisible places and by the time you see it, the problem is out of control.

The main point which I can’t stress enough is. If your basement was  flooded during a New York/ New Jersey storm, just make sure to get your property professionally restored straight away and don’t wait till the damage grows bigger!  

The faster the moisture is removed, the more damage you are preventing.

How To Protect My Home After Summer Flooding?

As we have mentioned, summer flash floods are a serious problem in areas such as  New York and New Jersey. The recent storms this July 2026 have shown us how quickly heavy rain will  flood basements and homes.

If your property was flooded, do not stop after removing the standing water.

Hidden moisture will lead to long-term damage if it is not treated.

Exit Mold handles flood damage and mold remediation. But it is best to prevent the mold before it damages, so that’s why we find the water that homeowners cannot see and fix the affected areas before the damage spreads.

If your home or business was affected by recent flooding in New York or New Jersey, call Exit Mold today. Call Exit Mold today! 

Do not wait for the musty smell.

Do not wait for mold to appear.

Get the water damage inspected and protect your property now.

Free For All Business Clients • Free Violation Alerts

For Access To Our Portal Reach Out

EXIT MOLD

Get an Estimate by Filling out the Form