why is water leaking into my basement after heavy rain?

- If you notice water is leaking into your basement after heavy rain, you might have a basement drainage issue. If you don’t have a proper drainage system in place, water can build up in the soil outside your basement walls and cause heaps of problems. Some of those include: 

 Hydrostatic pressure – If the soil around your basement starts to absorb excessive amounts of water, its volume can increase. This increase in volume will exert pressure against your basement walls, causing them to bow, lean, or sheer. If your walls start to move inward, cracks can begin to form, which can then allow water to leak inside your basement. Homes built in areas with high water tables are most susceptible to hydrostatic pressure. 

 Expansive soil – Soil that contains a lot of clay is what experts call expansive soil. When expansive soil absorbs water, it swells and pushes against your basement walls, causing them to move inward. Then, once that soil dries, the dirt will contract and allow your wall to move back outward. This back-and-forth movement can cause your walls to bow, lean, sheer, or crack. Once the structural integrity of your basement wall is compromised, water can then use any openings to enter your home. 

Frost-heaving – When soil freezes, two things can occur.

1. One, the volume and weight of the soil can increase, exerting pressure against your basement walls, causing them to bow, lean, sheer, or crack.
2. Two, the soil can lift up as it freezes. Then, when the soil dries, it settles back down. This up-and-down movement places pressure on your walls and can cause them to bow, lean, sheer, or crack. All of which can allow water to leak into your basement.

 -Here are a few ways to prevent water from leaking in your basement after heavy rain. 

1. Add a vapor barrier to your basement – A vapor barrier is a 10 to 20-mil thick sheet that is installed along your basement walls. Vapor barriers are great because they keep moisture from seeping into your basement and channel any collected water to a drain tile system, where it’s then carried away.
2.  Add a drain tile system – There are two forms of drain tile systems: interior and exterior. An interior drain tile system sits and collects water underneath your basement floor. An exterior drain tile system sits and collects water outside your basement walls. Both of these drain tile systems collect any water that’s building up and carry it to a sump pit. 
3.  Add a sump pump to your basement floor – A sump pump is a vital part of every basement drainage system. When water travels from your drain tile to the sump pit, the sump pump will activate once water reaches a certain level. Then, the sump pump will eject all the water out of your home using a discharge line. 
4.  Add a French drain to your yard – A French drain is very useful if your yard is prone to pooling water. A French drain is made up of a perforated pipe and is placed just below the surface of your yard. These drains then carry any collected water to the lowest part of your yard, a drainage ditch, street gutters, or a dry well (an underground structure that disposes of excess water). 
5.  Add extensions to your gutter downspouts – If your gutters are allowing water to pour too close to your basement walls, your soil can start accumulating moisture. Downspout extensions help carry that water further away from your home and basement. 
6.  Improve the grading of your property – The soil around your foundation should slope at least 6 inches within 10 feet away from your home. Otherwise, water will drain towards your foundation and exert pressure against your basement walls. This solution involves a lot of landscaping and if you are not comfortable doing it yourself, call a professional.