When a slope becomes a problem, a retaining wall becomes a solution—if it’s built correctly
In Saint John and across Northwest Indiana, retaining walls do more than “hold dirt.” A properly designed wall can stop erosion, create level outdoor living space, protect patios and driveways from runoff, and make a sloped backyard usable again. But walls fail for predictable reasons—poor base prep, wrong backfill, missing drainage, or building a taller wall than the site can support.
This guide breaks down what experienced retaining wall builders look for, what homeowners should ask before work begins, and how to avoid common (and expensive) wall failures—especially in clay-heavy soils and freeze/thaw conditions common to our region.
What a retaining wall should accomplish (beyond looks)
A retaining wall is a structural landscape feature. Even “short” walls can experience significant pressure from saturated soil, heavy rain events, and winter frost. When built correctly, your wall should:
If a contractor talks only about block style and color—without explaining base preparation and drainage—that’s a red flag.
The #1 reason retaining walls fail: water pressure
Water trapped behind a wall builds hydrostatic pressure. That pressure pushes outward and can cause bulging, leaning, cracking, or complete collapse—often after a heavy rain or spring thaw. That’s why professional retaining wall construction is as much a drainage project as it is a masonry project.
Common drainage components include a free-draining stone zone behind the wall, geotextile separation fabric to prevent clogging, and a collection pipe that carries water to a proper discharge point. Weep holes can also be used in certain wall types to let water escape. Industry guidance commonly recommends clean, angular aggregate (often around 1/2″–3/4″) and a meaningful drainage zone depth behind the wall to keep water moving. (tensarinternational.com)
How to choose retaining wall builders: a step-by-step checklist
Step 1: Confirm your wall type matches the job
Not all walls are built the same. A short, decorative garden wall is different from a structural wall holding back a hillside. If the wall is supporting a slope, a driveway edge, or a raised patio area, it typically needs a more robust base, compaction plan, and drainage system.
Step 2: Ask about base excavation and compaction (in plain language)
A strong wall starts below grade. Your builder should be able to explain: • How deep they excavate for the base
• What base material they use (not “whatever stone is on sale”)
• How they compact the base and in what lift thicknesses
Step 3: Require a drainage plan, not a guess
Drainage isn’t optional. In many installations, a perforated drain pipe is set at the base behind the wall and routed to daylight or a suitable outlet, with geotextile fabric separating soil from stone so fines don’t clog the system. (tensarinternational.com)
Weep holes can also help relieve water pressure in some wall designs, and guidance often places them periodically along the base to allow water to escape. (strucalc.com)
Step 4: Verify permitting requirements in Saint John before you build
Permits can come into play for structural work. The City of St. John’s public works permitting information lists retaining walls among projects that require a permit. (cityofstjohn.org)
A professional builder should help you understand what’s needed for your property (and whether engineering is required based on height, loads, and location). If someone tells you “permits are never needed,” pause and verify with the local building department.
Quick comparison: decorative wall vs. structural retaining wall
| Feature | Decorative / Garden Wall | Structural Retaining Wall |
|---|---|---|
| Primary purpose | Define beds, small grade changes | Hold back soil on slopes, protect hardscapes |
| Drainage | Often simpler (still important) | Designed drainage zone + outlet path is critical (tensarinternational.com) |
| Base prep | Moderate | Engineered-level attention to compaction and footing |
| Risk if built wrong | Cosmetic shifting | Leaning/bulging/failure, drainage issues, property damage |
Did you know? Fast facts that save walls
A Saint John, Indiana angle: retaining walls and drainage should be planned together
In Saint John neighborhoods, it’s common to see walls installed to level a patio area, frame a driveway edge, or terrace a backyard. The hidden issue is that water often follows the same path every storm—downspouts, swales, and low spots—and that water will find the back of your wall if it’s in the flow line.
If your project includes a wall near a patio, driveway, or a persistently wet section of lawn, plan for drainage alleviation at the same time. Forest Landscaping can also address broader yard drainage so the wall isn’t forced to “solve” a water problem by itself. If you’re comparing options, review our drainage alleviation services and how they pair with retaining wall construction.
Ready for a retaining wall that’s built to last?
Forest Landscaping designs and builds warranty-backed outdoor features throughout Northwest Indiana and the Chicago Southland—with owner involvement and craftsmanship-focused installation.
• Outdoor living spaces (level patio areas and steps)
• Paver cleaning, sealing & restoration (protect the investment)
FAQ: Retaining wall construction in Saint John, IN
Many projects do. The City of St. John’s permitting information lists retaining walls among projects that require a permit. Requirements can vary based on wall height, location, and what the wall is supporting, so confirm details with the local building department early in planning. (cityofstjohn.org)
Poor drainage is one of the most common causes. Water buildup behind the wall creates pressure that can push the wall outward, especially during heavy rain and freeze/thaw cycles. A drainage zone, filter fabric, and a properly routed outlet are key parts of a long-term solution. (tensarinternational.com)
It depends on wall design, height, soil type, and how much water reaches the wall. Weep holes can help release trapped water, but many modern installations rely on a drainage zone connected to a perforated collector pipe to move water to a controlled discharge point. (tensarinternational.com)
Signs include standing water, muddy areas that don’t dry, water flowing toward patios/driveways, or soil washing out during storms. If water is already a problem, a wall should be designed as part of a broader drainage plan—not a standalone feature.
Some walls can be reset, reinforced, or rebuilt in sections, but if the base, backfill, or drainage is wrong, a “surface repair” often doesn’t last. A professional evaluation should identify the root cause (settlement, water pressure, poor compaction, or site grading) before deciding on repair vs. replacement.