The foundation of your home holds everything above the ground in place. It bears the weight of your walls, floors, roof and any other structures. Without a strong, stable foundation your whole house could collapse. That’s why it’s so important to protect your foundation from any risks that could compromise its integrity, such as soil erosion.
Have you noticed any cracks appearing in your walls or floors becoming uneven? These can be signs that your foundation is being compromised by soil erosion. As the soil around your home’s foundation washes away, it removes essential support. Continued erosion will cause the foundation to slowly sink or shift out of place. This places undue stress on your home’s structures that were designed for an even foundation.
In this article, we will explore how soil erosion develops, its effects on home foundations, and most importantly – what you can do to prevent or stop soil erosion around your house foundation.
What Causes Soil Erosion Around Foundations?
Several factors can contribute to soil erosion around home foundations:
Heavy precipitation – Strong rain and flooding washes away exposed soil. Poor drainage exacerbates this by allowing water to pool around foundations.
Lack of vegetation – Plants and their roots hold soil firmly in place. Removing vegetation from around your home’s perimeter removes this natural defense against erosion.
Grading issues – Flat or improperly sloped land allows water to pool instead of draining away from foundations as it should. This saturates the soil.
Exposed soil – Construction that fails to replace removed topsoil, or landscaping that doesn’t replace eroded soil leaves foundations undefended against the elements.
These causes converge to create an environment where rainfall and runoff can rapidly erode exposed soil from around foundations. Once erosion begins, it tends to accelerate as more soil washes away over time.
Effects of Erosion on Home Foundations
When soil erosion undermines the area surrounding your foundation, it can have serious consequences for your home’s structural integrity:
- Foundations lose their supporting soil base, causing sinking, leaning or bowing. This puts stress on walls, doors and windows.
- Floors become uneven as one side of the foundation shifts lower than the other. This makes surfaces hazardous and aesthetically unpleasing.
- Cracks form in walls and cement as a settling foundation disrupts the building above. Moisture seeping in these cracks can damage interior walls and diminish insulation effectiveness over time.
- In severe cases of erosion, your entire foundation may destabilize and require expensive repair or full replacement to ensure home safety. Rebuilding a foundation costs tens of thousands of dollars or more.
7 Ways to Prevent Foundation Erosion
The following methods can help ensure your soil and foundation remain solidly protected as they were designed. These tried-and-true techniques should be part of maintaining any home.
1. Plant Vegetation Around Foundations
Plant shrubs, flowers and grass around foundations. Well-chosen greenery holds soil in place with its roots while also beautifying your property. Avoid putting large-rooted trees too near foundations.
2. Install Gutters and Direct Downspouts
Install gutters and downspouts and direct runoff 5-10 feet from foundations. This lets rain drain safely away without eroding surrounding dirt. Inspect them regularly for needed cleaning or repairs.
3. Check Foundation Grades
Check foundation grades and ensure they slope away at 3-5% for 10 feet. A flat surface risks pooling water against foundations, but a proper angle encourages drainage.
4. Use Retaining Walls
Install retaining walls at the base of slopes to keep soil from washing downward during heavy rains. Terraced walls add stability to steep grades near foundations.
5. Consider Foundation Plantings or Paving
Consider using foundation plantings or concrete paving near foundations instead of bare dirt in areas where landscaping won’t suffice. These solid surfaces don’t erode over time.
6. Construct a French Drain System
Construct a French drain system to intercept groundwater seepage before it reaches foundations. Its gravel-filled trench and PVC pipe redirects moisture away.
7. Stabilize Loose Soils
Stabilize any very loose soils near foundations. Consult professionals about installing geotextile erosion control fabrics, low walls or other secure barriers tailored for your specific erosion risks.
In summary, keeping exposed soils shored up with plants or other hardy covers while ensuring efficient water runoff through proper drainage is a foundation’s best defense against long term damage from soil erosion.
Repairing Foundation Erosion Damage
If your foundation does start showing erosion effects such as cracks or sinking, it’s time to evaluate repair options. Techniques used depend on severity but aim to restabilize the eroding area and shore up structural integrity. Remediation projects are best performed by experienced foundation experts.
For minor settling, a common fix is:
Polyurethane foam injection cracking. Holes are drilled allowing expandable foam to enter cracks and lift sunken areas back into position from underneath.
When erosion undermining is more extensive, contractors may:
- Excavate around the issue and install bracing support. Piers or other stabilizers are added while concrete or non-shrink grout solidifies a new robust base.
- Use mudjacking or concrete lifting. Drilled holes inject fluidizing drilling mud or grout under sunk areas, floating them back up before hardening sets in.
- Install an interior or exterior foundation drainage system like french drains to prevent further issues by redirecting groundwater.
- Insert helical piles or struts if lateral soil pressures pulled a foundation significantly out of place. These provide internal reinforcement.
What Types of Soil Are Prone to Erosion?
Not all soils are equally vulnerable to erosion. A property’s soil composition can help assess erosion risks and determine the best prevention methods. Here are erosion control solutions specific to common soil types:
Clay Soils
Soils high in clay content are prone to cracking when dry. Heavy rains can then wash away soil particles through these cracks. Clay becomes muddy when saturated, further increasing runoff and erosion potential.
- Establish vegetation quickly to occupy the soil surface and secure cracks
- Install fabric erosion control blankets under plants to armor bare cracks until established
- Terrace slopes and direct runoff from downspouts to stable outlets via underground drainage
Sandy Soils
Soils high in clay content are prone to cracking when dry. Heavy rains can then wash away soil particles through these cracks. Clay becomes muddy when saturated, further increasing runoff and erosion potential.
- Add compost or other organic material to bind grains more cohesively
- Cover exposed sand with synthetic or natural erosion control blankets/mulches until replanted
- Install silt fences below grading to capture and filter runoff
Loamy Soils
The ideal soil for gardening and foundation plantings, loam has a mix of sand, silt, and clay. It maintains solid structure while draining well. With proper care, loam experiences minimal erosion.
- Maintain existing healthy plant/shrub coverage around foundations
- Add mulch in landscaped areas for moisture retention and weed suppression
Calcareous Soils
Soils containing calcium carbonate are vulnerable to water’s dissolving effects. Precipitation and runoff can carve dissolving sediment away from these soils over time.
- Construct a perimeter swale to direct precipitation away from foundations
- Increase sloping and planting on grade to quicken runoff time
- Use ditch or french drain systems to capture and redirect runoff
Recently Disturbed Soils
Any fill or relocated topsoils lack a mature, stabilizing root structure. Until revegetated, these soils are highly prone to being washed or blown away by weather. Proper compaction helps but risks remain higher short-term.
- Prioritize groundcover and erosion control seeding or mulching
- Stage construction to limit bare soil exposure time
- Maintain silt fences through revegetation period
- Steep Slopes
Steeply Sloped Soils
The steeper the grade, the more potential energy rainfall collects as runoff. This runoff can gain enough power on slopes to dislodge and carry soil particles downhill if unmitigated. Terracing helps tame erosion on steep lots.
- Properly install and maintain retaining walls or terracing
- Supplement with erosion control blankets on newly graded slopes
- Concentrate surface runoff in stable drains rather than sheet flow
Keeping Foundation Drainage in Check
While first installing gutters, downspouts and drainage features, don’t assume you’re fully protected from erosion – maintenance must continue. Here are important checks of your foundation’s ongoing drainage:
-Each season, visually inspect gutters and downspouts for leaves/debris jams limiting flow. With clogs, water overflows onto roofs and soil instead of draining away as designed.
-Ensure downspouts direct rain at least 5-10 ft from foundations (not onto them) and that splash blocks or extensions route overflowing stormwater farther out.
-Check drainage slopes still allow water to run clear of foundations without installing pooling. Regrade if rainfall has eroded grading over time.
-For French drain systems, make sure gravel still looks clear of silt buildup which could disrupt water percolation through the trench and outflow point.
-Watch for any signs of new depressions, soil cracks or settling developing near the building perimeter despite your drainage setup. These warrant assessment by a foundation expert.
If your home’s foundation is at risk due to soil erosion, follow the instructions and recommendations given in this article. However, consulting a professional foundation repair expert can prove to be a wiser measure. Monitor for erosion indicators, and confirm your drainage systems need no cleaning or improvements. Care for your foundation now to avoid serious structural issues or expensive repairs in the years ahead. With proper maintenance of soil and drainage, your foundation should last the life of the building you call home.