A retaining wall is a structural element — and one of the most common places contractors cut corners. In Des Moines clay soils with 42-inch frost depth, that translates to failure within 3–5 winters. DSM Concrete Pros engineers and builds walls to last.
Wall Types
- Poured concrete retaining walls — for tall (6+ ft) or load-bearing applications
- Segmental retaining walls (SRW) — Versa-Lok, Belgard, Allan Block, etc.
- Decorative block — split-face, weathered, multi-color blends
- Boulder walls — natural stone, freestyle stacked
- Tiered retaining systems — multiple shorter walls for slope management
Engineering Requirements
| Wall height | Engineering |
|---|---|
| Under 4 ft, no surcharge | DIY-eligible, we build to standard spec |
| Over 4 ft OR surcharge load | Engineered drawings + permit required |
| Over 6 ft | Engineer-stamped, special inspection during build |
Surcharge = anything heavy above the wall: driveway, parking, building, slope load.
Drainage Is Everything
Every wall we build includes:
- 4” perforated drain tile at base of wall
- 12” of washed rock backfill against wall face
- Geofabric separator (keeps fines out of drain rock)
- Daylight outlet or tied to storm drain
- Weep holes (poured walls) or open joints (block walls)
Walls without drainage hold hydrostatic pressure and fail. Always.
Pricing
| Wall type | Range (per sq ft of face) |
|---|---|
| Standard segmental block, under 4 ft | $30 – $45 |
| Engineered segmental wall, 4–8 ft | $45 – $70 |
| Poured concrete wall, residential | $50 – $75 |
| Decorative split-face or premium block | $55 – $80 |
| Tiered systems | Combined linear pricing |
A typical 50 ft x 4 ft segmental wall runs $7,500–$10,000.
Process
- Site visit, measurements, grade survey
- Engineering review (if required by height/load)
- Polk County permit pull
- Excavation + footing prep
- Drain tile + base course
- Wall construction with geogrid reinforcement
- Cap installation + backfill
- Site cleanup
Typical timeline: 1–2 weeks from start.
Common Des Moines Metro Wall Scopes
Sloped lots in newer subdivisions — Echo Valley in Norwalk, Copper Creek in Pleasant Hill, Kettlestone in Waukee, Prairie Trail in Ankeny — drive most of our residential retaining wall scopes. Typical project sizes:
| Wall type | Dimensions | Project range |
|---|---|---|
| Garden edge wall (under 4 ft) | 30 lf × 2.5 ft | $2,500 – $4,500 |
| Standard residential retaining (4 ft) | 40 lf × 4 ft = 160 sq ft | $4,800 – $7,200 |
| Engineered residential (6 ft) | 50 lf × 6 ft = 300 sq ft | $13,500 – $21,000 |
| Tiered system (two 4-ft walls) | 80 lf total | $11,000 – $16,000 |
| Commercial site wall (8 ft) | 60 lf × 8 ft = 480 sq ft | $22,000 – $38,000 |
Permits and Engineering by Municipality
Most metro cities trigger permit + engineering review at the same thresholds (over 4 ft exposed face or any surcharge load), but specifics vary:
- Des Moines — engineered plans required > 4 ft; surcharge from driveway or parking always triggers engineering
- Polk County (unincorporated) — engineering > 4 ft; geotech sometimes required > 6 ft
- West Des Moines — engineering > 4 ft, ZBA review if wall is within front setback
- Waukee, Ankeny, Grimes — newer subdivisions often have HOA design review on top of municipal permits
- Warren County (Norwalk) — engineering > 4 ft; different inspection contacts
We handle the permit pull and engineer coordination as part of every wall scope over 4 ft.
Drainage Failure: The #1 Reason Walls Fail
Roughly 80% of failed retaining walls in the Des Moines metro that we rebuild failed because of inadequate drainage, not structural failure. Iowa clay holds water seasonally. Without drain tile, washed-rock backfill, and a daylight outlet or storm tie-in, hydrostatic pressure pushes a wall outward 1–2” per spring until it cracks or tips. Every wall we build gets the drainage detail before block one goes down.
Service Area
Retaining walls built across the Des Moines metro — residential, commercial, municipal — West Des Moines, Ankeny, Urbandale, Waukee, Clive, Altoona, Johnston, Grimes, Pleasant Hill, Norwalk.