How Soil Composition Affects Basement Waterproofing

Just like the type of soil in your garden has an influence on what kinds of plants will grow, it’s got a big effect on how effective certain methods of waterproofing may be. 

Different textures and compositions in the dirt around your home can have a huge impact. If your soil is loose, water will act differently as it drains than it would with a tighter packed type of dirt. This means that some methods may make more sense in a silty area than say a loamy one and so on.

Before we can get into it, let’s talk about soil composition.

Understanding Soil Composition

Soil isn’t just “dirt”. It’s a thriving and interesting biome that varies hugely around based on what it’s comprised of for the reason that particular location.

Occasionally it might be “sandy”, in other’s “loamy” or “clayey” or “silty”, based on what it’s comprised of.

The component aspects of soil let you know a great deal concerning the geological good reputation for your neighborhood in addition to provide you with some good pointers if you are a eco-friendly-thumb, but we’re here to speak about waterproofing.

For the purposes, probably the most interesting feature of the property’s soil is when water flows through it and also the hydrostatic pressure it may exert in your basement walls and floor.

How Soil Types Affect Water Flow and Pressure

Depending on how dense the soil type around your home is, water will drain through it differently and this affects how much pressure the earth around your foundations places on your walls.


If the soil around your home is sandy, you’re in luck when it comes to keeping your basement dry. Thanks to being very permeable, water will drain away quickly and hydrostatic pressure is minimized, making waterproofing relatively straightforward.


Clay has a habit of retaining water, thanks to how impermeable it is. This means that it takes longer for rainwater to drain away from your foundation walls and increases the hydrostatic pressure placed upon them.


Silty soils are harder to classify in terms of how they affect your options for waterproofing. If left undisturbed, silt heavy soils have a moderately good level of permeability. The problem comes when they’re compacted as this can mean they lose much of their ability to drain away water. Overall, it’s best to think of silty soils as “variable” when considering how they interact with your basement’s waterproofing.


Loamy soils are neither particularly great at draining water nor bad for retaining it. The challenge here comes from their innate variability. Water may move fairly freely through them or be retained and pressure may be light in one area and heavy in another.

Impact of Soil Composition on Basement Waterproofing Strategies

So, now we know how water behaves in different types of soil, how does that impact on our options for basement waterproofing

Drainage Considerations

It’s worth thinking about what you can do to aid water’s progress away from your walls, especially if you live in an area with a denser soil type like clay or compacted silt. 

Water follows the path of least resistance, so why not supply it with a nice easy route through a French Drain? These horizontal drainpipes can guide water away from your home to where it can do no harm.

If you live in an area with a looser soil type like sand your efforts are probably better focused elsewhere.

Waterproofing Materials

The soil type around your home also has an impact on which materials are most suitable for your waterproofing efforts too.

If your area has a particularly acidic soil type, certain materials may degrade faster than they otherwise would.

Foundation Protection

If you’re in an area with soil that tends towards retaining water rather than letting it drain away easily, you’ll have to consider not only keeping water from seeping through your walls, but from your basement floor as well.

Sump Pumps can be a great solution in particularly clay heavy soils, keeping water flowing away from your home.

Landscaping and Grading

Grading is the process (usually done when a property is built) of ensuring that the land around your home slopes away from it, allowing water to flow relatively freely away from your walls.

While it’s always important to ensure your grading is suitable, it’s particularly vital in high water retention areas like those with clay or certain types of loam heavy soils. 

In these areas it’s a good idea to ensure the slope is more pronounced than it need be.

Best Practices for Assessing and Addressing Soil-Related Waterproofing Issues

Now that we’ve considered the different types of soil and how they impact our options for waterproofing, how do we go about making sure we get the best results?

Professional Assessment

It’s never a bad idea to consult a professional basement waterproofer, especially when it comes to something as serious and potentially costly as basement waterproofing. 

From identifying the kind of soils you’ve, to counseling around the ideal materials, an expert assessment will place you on course, potentially not waste time, effort and cash on ineffective methods.

Regular Maintenance and Monitoring

Keeping track of the soil around your house is never an awful idea, but it’s particularly important if you reside in a silty or loamy area. Because these particular kinds of soils are vulnerable to altering how permeable they’re under different conditions, having to pay focus on them can provide advanced warning of problems.

Adaptive Waterproofing Measures

Obviously, having the ability to change strategy as conditions change is definitely the very best policy. When focusing on waterproofing your basement it’s rarely an awful idea to pay for all of the bases.

While a French drain or sump pump might not be as essential in sandy soils because they are in clay, they are able to still help you save in desperate situations. Likewise, crystalline coatings, crack repairs and exterior wrapping will always come in handy.