A flooded basement can be a real disaster for a homeowner, but water in the basement is a surprisingly common problem. With water in your basement, precious belongings can be seriously damaged if not destroyed. Walls and floors can be permanently stained. Even worse, a wet or moist basement that is left untreated can develop mold growth that can spread to the rest of your home. So what can you do if your basement has water in it?

What to Do When Your Basement Floods [infographic]

What Causes Water in the Basement?

One way to get water in your basement is when something breaks. Your house is full of pipes and plumbing. If something breaks, water can often end up in the basement. Many homes keep their washing machines in the basement, so a burst pipe or cracked hose can easily send water all over the basement. Another common basement appliance is the house’s water heater. If a water heater bursts, gallons of water can pour out into your basement.

Another issue that can allow water into your basement is a failed sump pump. A sump pump exists for one reason only: to keep water from outside of your basement for getting in. But if a sump pump fails, it can’t do its job and water can work its way into the basement. Common reasons a sump pump can fail include power outages, parts failure, or improper installation. One way to avoid these problems is to install an alarm so you know if the pump stops working, as well as a backup system to take over if something goes wrong.

Those sources of water come from something that is broken. But what if you have water in your basement and there are no broken pipes or pumps? The problem may be in your basement’s waterproofing.

The Clay Bowl Effect

When a home with a basement is being built, the builders have to start be excavating a hole slightly larger than the size of the home that will be built. Into that hole, they can pour a concrete slab for a foundation, and then add cinder block or concrete walls to close off a basement. Once the basement has been built, the builders can put the excavated dirt back into the space around the basement to fill it in.

The main issues with water leakage come from the fact that the dirt that is put back in the excavated hole, called backfill, is not as dense as the dirt around it. This makes sense when you think about how the excavation was done. The builders had to dig into dirt that had been settling for hundreds of years or more, becoming quite dense as small air pockets are slowly filled in. But when the builders return some of that dirt to fill in the space around the basement, the backfill will have many more air pockets than the virgin settled dirt around it. This means that when it rains the backfill will hold more water than the virgin dirt, creating the effect of a “clay bowl” made of virgin dirt that collects water in the saturated backfill.

As the backfill becomes saturated, the water exerts hydrostatic pressure. Water is heavy, and hydrostatic pressure is the weight of all of that water pushing down and outwards, looking for somewhere to go. As the water collects and the pressure increases, water will try to find its way into the basement any way it can.

The most common place for water to enter the basement is at the seam between the floor and the wall. Water can also enter through cracks in the floors or walls of the basement. Concrete shrinks as it cures. Sometimes this shrinkage can result in cracks that develop over time. If the pressure is great enough and the foundation was not properly waterproofed, water may even seep into the basement through the tiny pores in the basement walls. This is especially common with the more porous cinder block style construction.

The Stack Effect

Even if no water is seeping in from outside of the basement, a basement can collect water and moisture due to the “stack effect”.

A house is made up of several layers. The lowest layer is the basement or crawlspace that is at least partially underground. Above that is one or more stories of living space. At the very top, there is usually an attic. Hot air always rises, so as hot air leaves through the attic and upper levels of the house, it creates a vacuum that draws in air from outside through the lower levels and the basement. During the hot and humid summer months, the introduction of warm, moist air into the basement can cause condensation, due to the principle of relative humidity.

Relative humidity is a measure of how much moisture the air is holding. It is expressed as a percentage of the total possible moisture the air could hold. When the humidity outside reaches 100%, it rains. The humidity is called “relative” because it is relative to the total capacity of the air to hold moisture. Warm air can hold more moisture than cool air, so if the air is at 80% of capacity at 80 degrees, which we call 80% humidity, and the temperature goes down, even with no new water the relative humidity will increase since the total capacity is reduced.

Basements tend to stay relatively cool year-round. When warm, humid air from outside is drawn into the basement through windows or vents, the air cools. Without any new water being added, the cool air now has a higher humidity than it did outside when it was warm. This can lead to two problems. First, if it was already quite humid outside, it is likely that as the air cools it will exceed 100% humidity. The extra moisture will condense on cold surfaces in the basement, such as wood, metal, and concrete. Eventually the water drips and pools, and you have some real water damage in your basement.

But even if you don’t get condensation, just the increased humidity can be a problem. As humidity rises above 60%, you run the risk of mold. Mold needs moisture to survive, so basements and crawl spaces with moist air make great homes for mold. Mold reproduces by releasing millions of spores into the air. These spores can cause allergies and even sickness. And as the air moves through your house, it can carry these spores well beyond the confines of your basement.

What to Do If Your Basement Has Water

If your basement has water, don’t wait to deal with it. Even if it is just humid and moist, the longer you wait, the more damage may be occurring. Don’t know where to turn? Try these great TrustDALE certified businesses:

When you work with TrustDALE certified businesses, you have the benefit of Dale’s 7-Point Investigative Review and his exclusive Make-it-Right Guarantee. So if you have water in your basement, call one of these companies today

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