Questions Homeowners Always Ask About Retaining Walls — Answered

Retaining walls are one of the projects we're asked about most frequently across Lebanon, Mt. Juliet, and the rest of Wilson County. Middle Tennessee is hilly, and sloped lots need retaining solutions. Here are the most common questions — answered honestly.

What does a retaining wall actually do?

A retaining wall holds soil in place on a sloped site. Without it, slopes erode, mulch washes down after every rain, and usable yard space is limited to whatever's flat. A retaining wall converts a slope into terraces — creating level usable areas, stopping erosion, and making the property dramatically more functional.

They also address drainage. A well-designed retaining wall system includes drainage provisions behind the wall to prevent hydrostatic pressure from building up — which is one of the primary reasons walls fail.

What materials are used for retaining walls?

The most common options in the Lebanon area:

*Segmental retaining wall block* — engineered concrete blocks designed specifically for retaining walls. Brands like Allan Block, Versa-Lok, and Belgard. Highly durable, very clean appearance, available in many colors and textures. Best for most residential applications.

*Natural boulders* — large decorative stones, typically Tennessee fieldstone or sourced from local quarries. A more natural, organic look. Excellent for larger properties or properties with a rustic aesthetic. Very durable when properly set.

*Timber* — pressure-treated railroad tie-style walls. Lower cost, shorter lifespan (15–20 years before significant deterioration), and no longer our first recommendation for permanent installations.

*Poured concrete or CMU* — used for larger structural applications, typically commercial or for very tall walls requiring engineered solutions.

How tall can a retaining wall be?

For segmental block walls, most residential applications are 2–4 feet. Walls exceeding 4 feet in height typically require engineered design in Tennessee and may require a building permit, depending on your municipality.

For very significant grade changes, the better solution is often a series of terraced walls with planted or hardscaped areas between them — rather than one tall wall.

Does a retaining wall require a permit in Lebanon, TN?

It depends on height and location. Lebanon, Mt. Juliet, and Wilson County each have their own thresholds. As a general guideline, walls over 4 feet in height or walls near property lines or structures may require a permit. We pull all required permits as part of our project management — you don't have to navigate the permit office yourself.

What does a retaining wall cost?

For Lebanon, TN homeowners using segmental block:

• Small walls (under 30 linear feet, 2–3 feet tall): $4,000–$9,000
• Mid-size walls (30–60 linear feet, 3–4 feet tall): $9,000–$20,000
• Large walls or significant terracing projects: $20,000–$60,000+

Natural boulder walls are priced differently and depend heavily on stone sourcing and wall complexity.

Why do retaining walls fail?

Almost always: drainage failure. Water pressure building up behind a wall (hydrostatic pressure) is the number one cause of retaining wall blowouts. Every wall we build includes drainage provisions — typically a layer of drainage aggregate behind the wall face and perforated pipe at the base to carry water away.

Walls also fail from improper base preparation, inadequate geogrid reinforcement on taller walls, or using materials not designed for retaining applications (decorative garden block, which lacks the structural interlocking of engineered retaining wall block).

How long does a retaining wall last?

A segmental retaining wall built correctly with proper drainage should last 30–50 years with minimal maintenance. Natural boulder walls last essentially indefinitely. The limiting factor on any wall's lifespan is drainage — walls without proper drainage provisions fail in 5–15 years regardless of material quality.

We're ready to talk through your specific property. Call 615-487-2965 or fill out our contact form for a free on-site consultation.