Retaining walls are one of the most structurally consequential things we build — and one of the most misunderstood. Done right, a retaining wall solves an erosion problem, creates usable yard space, and looks like a permanent, intentional part of the landscape. Done wrong, it tilts, separates, or fails within a few years, leaving you with a bigger problem than you started with. At Hometown Landscape, retaining walls have been a core part of our work for over 27 years, and we’ve built — and repaired — enough of them throughout Montgomery County, Howard County, and Prince George’s County to know exactly what separates the ones that last from the ones that don’t.
We recently completed a terraced retaining wall system for a client in Olney where the rear yard sloped approximately 8 feet from the back of the house to the fence line. We built three tiered walls using natural fieldstone — each standing under 4 feet to stay below the engineered drawing threshold — creating two flat terraces between them. The lower terrace became a lawn area for the kids; the upper became a patio and garden space. The project took about two weeks and fundamentally changed how the family uses their backyard.
Types of Retaining Walls We Build
The right wall type depends on how much earth it needs to hold, the desired aesthetic, your budget, and whether the wall is visible or mostly functional. We build with four primary material types:
- Natural stone (fieldstone, bluestone, granite) — Best for naturalistic settings, wooded lots, or homes with existing stone features. Dry-stacked or mortared depending on height and application. Ages beautifully and is highly durable if built on a proper base.
- Segmental retaining wall block (Allan Block, Versa-Lok, etc.) — Engineered for structural performance with a consistent finish. Available in many colors and textures. Best for higher walls or situations where precise geometry matters.
- Poured or block concrete — Utilitarian but extremely strong; typically used for walls that will be faced or covered rather than left exposed.
- Timber (pressure-treated or railroad tie) — Lower cost, appropriate for garden bed edges and walls under 3 feet where structural load is minimal. Lifespan is shorter than masonry but sufficient for many applications.
What Makes a Retaining Wall Last in Maryland
Two things fail most retaining walls in our region: inadequate base preparation and poor drainage. Maryland’s clay soils hold water, and water-saturated soil behind a wall generates hydrostatic pressure that will eventually push any wall over if drainage isn’t relieved. Every wall we build includes drainage aggregate (crushed stone) immediately behind the wall face and a perforated pipe at the base of the wall to route water away from the structure. This step is skipped on a lot of budget wall installations — and it’s why those walls fail.
Base depth matters too. Maryland’s freeze-thaw cycles require walls to be founded below frost depth (approximately 24–30 inches in our zone) or built with flexible systems designed to move slightly with ground shifts. A wall footed at 6 inches will heave; a wall footed correctly won’t.
Permits and Engineering
In Montgomery County, Prince George’s County, and Howard County, retaining walls over 4 feet in height (measured from the bottom of the footing) typically require a building permit and engineered drawings. We coordinate permitting as part of our project management. Walls under 4 feet generally don’t require permits, though setback rules from property lines still apply.
Ballpark Pricing
Retaining wall costs vary significantly based on material choice, wall height, drainage complexity, and access. As a general guide for projects in the Maryland/DC area:
- Timber walls (under 3 ft): $25–$40 per square face foot installed
- Segmental block walls: $45–$75 per square face foot installed
- Natural stone walls: $60–$120 per square face foot installed
- Walls requiring engineering/permits: Add $1,500–$4,000 for drawings and permit fees depending on complexity
A typical 30-linear-foot, 3-foot-high segmental block wall with drainage runs $8,000–$15,000 installed in this market. Natural stone for the same wall would be $12,000–$20,000. We provide detailed estimates after an on-site visit — these ranges are starting points only.
Frequently Asked Questions
Do you need a retaining wall, or could grading solve the problem? Sometimes grading alone can address a slope — retaining walls are necessary when the grade change is too steep or abrupt for grading to be practical, or when you need to create a vertical face to recover usable flat space. We’ll tell you honestly which approach makes more sense for your situation.
How do you maintain a retaining wall? Well-built masonry walls are low maintenance. You should inspect annually for any shifting at the top course, clean out weep holes if present, and address any vegetation growing in joints before roots can cause structural damage. Timber walls should be inspected every few years for rot at ground level.
Can you build a retaining wall on a property line? This depends on your jurisdiction. In most Maryland counties, walls must be set back a minimum distance from property lines, and you may need neighbor notification or consent for walls near the boundary. We’ll identify any constraints before design begins.
“We had a slope that had been eroding for years — losing soil every time it rained, covering our lower patio with runoff. Hometown built a two-tier wall system that solved the erosion completely and gave us a new planting terrace in the process. Two years later, everything looks exactly as it did when they finished.” — Rockville, MD homeowner
To discuss a retaining wall project, call us at 301.490.5577 or request a free estimate online. We serve residential and commercial clients throughout Montgomery County, Prince George’s County, Howard County, and the greater Washington DC metro area.
Landscape and Outdoor Living Across the DMV
Hometown Landscape serves homeowners across Montgomery County, Howard County, and the wider Washington, D.C. region with landscape design, hardscape, outdoor living, and outdoor carpentry from our Burtonsville home base.
