7 Reasons Why Water Is Rising Through Your Floor—And How to Fix Them

If you notice a growing wet spot on your floor or water coming up through the basement floor, it could be a huge cause for concern. If you don’t find and fix the problem quickly, this moisture could lead to mold and pests. Here are some common causes of water coming up through the floor and how to solve them.

What to Check When Water Is Coming Up Through the Floor

When you first notice rising water, there are a few main reasons this could be happening. You might have a plumbing leak, or it could actually be coming through the ceiling. If not, the issue could be anything from a leaky in-floor heating system to groundwater seeping through the foundation of your home.

1. Check the Ceiling for Leaks

If you see a puddle on the floor, you might think it’s rising up through your home. This can sometimes be the case, but more commonly, you have a ceiling leak. This may happen after a period of heavy rain.

Start by looking or listening for a leak. If one isn’t immediately noticeable, search the ceiling above the wet spot on the floor for any stains or signs of moisture, such as a damp or soggy ceiling.

If you do find a leak, use a wet vacuum or a mop to soak up the water, then place a bucket and/or tarp down to catch additional water. You’ll need to hire a local plumber to fix the leak. It can be dangerous to get on the roof to find the area, and this issue can quickly cause mold or rot to places like your ceiling, floors, and drywall.

2. Monitor the Water Meter

A leaky ceiling isn’t always the culprit, though. You might also have a plumbing leak that is seeping through your floors.

If you don’t immediately notice a leak, you can check your water meter to determine whether or not a plumbing leak is the issue. To do this, turn off all your water sources, then check the water meter. Wait three hours, then check the meter again. If it moved, you have a leak, and you’ll need to call a contractor to track down the source.

If the meter hasn’t moved, the water leak is coming from an outside source (like groundwater) that's causing the water to come up through the floor.

3. Leaking Underfloor Heating

If you have an in-floor heating system, the water that keeps these floors warm can leak out.

Your water meter will indicate a leaking in-floor heating system, but you can’t always see this leak. In-floor heating systems involve pipes that run through concrete slabs or just below your floors. Still, the leak can seep through floors, causing mold or even pest infestations.

A flooring contractor or in-floor heating system specialist will use infrared thermal cameras on the floors to find the source of the leak and repair it, plus treat the area for mold. You can also try to track down the leak by purchasing your own infrared thermal imaging device, which will cost anywhere from $50 to $500.

4. Excess Groundwater or Rising Water Table

You head down to the basement to run a load of laundry, only to find water coming up through the basement floor. This could be a sign of excess groundwater or a rising water table.

When the soil has too much moisture, or the water table starts rising to the level of your basement or home foundation, hydrostatic pressure causes the water to move into cracks in your home, unless the basement is properly waterproofed. This can also be caused by a neighbor’s home, if it is located on a hill, draining downward towards your property. 

Start by checking the sump pump, which is designed to move water away from the house. Too much hydrostatic pressure can cause the sump pump to burn out over time. You might need to simply clean the sump pit of debris. But if your sump pump is seven to 10 years old, it’s probably time to replace it.

Another way to help alleviate the excess groundwater on your property is to install a drainage system, like weeping tiles that drain into a sump pit or an interior drainage system. The weeping tile may have a funny-sounding name, but it helps collect groundwater and push it to a different area. An interior drainage system sits where the wall and floor meet, and it is also designed to drain excess water into a pipe and away from the home.

Either way, calling a pro to fix a slab leak is the best method to prevent extensive water and foundation damage. You’ll also want to consider hiring a local contractor to waterproof your basement and prevent future leaks.

5. Excess Water Coming in From Doors and Windows

If it’s not the pipes and it’s not the foundation, the water might be coming in through the windows and doors of your home. Improperly sealed windows can leak on a rainy day, and the water can drain down the wall and into the floors and subfloors.

If this happens, you need to start by sealing the windows with caulk. You might need to replace older windows or doors that leak with newer models if the problem persists.

You’ll also need to start drying out the room quickly with dehumidifiers and fans to avoid mold, especially if the water has seeped into the subfloor. Call a window pro to take a look. If the windows are old and beyond repair, you may need to hire a local window company to install new ones, which will cost between $200–$450 per window.

6. Clogged or Broken Drains

Clogged or broken drains could be causing water to seep through your floor. These drain lines carry water from your home's water fixtures to a central drain pipe, which then carries it away from your home and into a septic tank or city wastewater system. If the drain lines become clogged or broken, the water will flow back into your home and cause flooding. Any cracks in the drain line will also cause water to leak through the floor. 

You can typically identify a drain line problem by looking out for unpleasant odors creeping from your water fixtures. A slowly draining sink is also a telltale sign. A problem with your drain line will require professional help, so it's best to call a local plumber if you suspect this issue. 

7. Clogged Gutters or Poor Drainage

Clogged gutters or poor drainage are some more causes of water creeping into your home. Your gutters are designed to collect water and guide it away from your home’s foundation. If your gutters become clogged with debris, like sticks and leaves, water will overflow from the gutters and cause water to pool below. Combine that with poor drainage around your house, and you’ve got a recipe for unwanted water entering your home.

You can DIY gutter cleaning twice a year, or after major storms, to make sure they’re flowing well. It’s also a task you can outsource to a gutter cleaning service. You can improve the drainage around your home by installing drains in areas that tend to collect rainwater. French drains, trench or channel drains, underground downspouts, and catch basins are popular drainage options. Call a local drain pipe installer to handle this type of project, to ensure water is properly directed away from your home. 

Fixing Damage After Leaks or Flooding

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Once the floors, ceilings, or walls are wet, water damage can happen quickly; mold and mildew can start growing and spreading in just 24 to 36 hours. The first step is to call a nearby water damage restoration pro. Don’t waste time if you don’t immediately know the cause of the leak, because it needs to be tracked down and fixed as soon as possible.

While you wait for the contractor to arrive, you can start drying out your home using the following steps.

• Open the windows, so long as it isn’t rainy or humid outside.

• Turn on ceiling fans and box fans.

• Move wet or water-damaged furniture out of the room, ideally outside in the sunlight to dry.

• Pull up the wet part of the floor to dry and treat for mold.

• Bring in a dehumidifier to help pull moisture from the air.

• Use a wet vacuum to suck up any pooling water on the floor. Don't use a regular vacuum, as this poses an electrocution risk.

• Use a mop to soak up smaller amounts of water.

• Replace the carpet padding (and possibly the carpet) if it became wet to prevent mold.

The cost of water damage restoration can run between $1,300 to $6,000, depending on the severity of the situation, but this work is necessary to ensure you prevent mold and mildew growth.