Costs checked October 2026
Retaining Wall Cost in Brentwood, CA
There is no published Brentwood price list, so this page uses named national cost guides, shows the math for common sizes, and lists what moves the price. Treat every number as a range to compare bids against, not a quote.
The short answer
HomeGuide puts the average retaining wall at $35–$65 per square foot of wall face, labor included, with labor making up 40–60% of the cost (HomeGuide). Angi reports a national average project of about $6,084, with most projects between $3,192 and $9,206 (Angi). Wall face area is height times length, so a taller wall costs more than a longer one of the same area would suggest.
Cost per square foot by material
| Material | Range per sq ft | Source |
|---|---|---|
| Wood / timber | $15–$30 | HomeGuide; Angi |
| Concrete block (segmental / CMU) | $15–$40 | HomeGuide |
| Poured concrete | $20–$45 (Angi: $30–$50) | HomeGuide; Angi |
| Natural stone | $20–$95 (Angi: $20–$100) | HomeGuide; Angi |
| Brick | $30–$60 | HomeGuide |
Per square foot of wall face. The concrete, block and stone and wood pages explain each material. HomeGuide's concrete guide lists $15–$45 overall and $45–$270 per linear foot for 3–6 ft concrete walls (HomeGuide concrete).
Worked examples (the math shown)
| Wall | Face area | At $35–$65 / sq ft |
|---|---|---|
| 4 ft high x 20 ft long | 80 sq ft | $2,800–$5,200 |
| 5 ft high x 30 ft long | 150 sq ft | $5,250–$9,750 |
| 4 ft high x 100 ft long | 400 sq ft | $14,000–$26,000 |
Cross-check with Angi's per-linear-foot range of $40–$360, which grows with height (about $40–$200 per foot for a 2 ft wall, up to $360 or more for a 6 ft wall): 100 feet at that range is $4,000–$36,000, which shows how much height matters. Small jobs can run into minimum charges; HomeGuide lists project minimums of $1,500–$3,000.
These are arithmetic illustrations from national averages, not Brentwood quotes. Soil, access, drainage and a permit requirement can move a real price well outside them.
Costs that are often separate
| Item | Typical range | Source |
|---|---|---|
| Footings | $18–$55 per linear ft | HomeGuide |
| Drainage (French drain) | $10–$85+ per linear ft (concrete guide: $10–$30) | HomeGuide |
| Waterproofing | $2–$10 per sq ft | HomeGuide; Angi |
| Removing an old wall | $15–$30 per linear ft | HomeGuide |
| Permits | $50–$450 | HomeGuide; Angi |
| Structural engineering | $350–$750 (Angi) to $500–$2,000+ (HomeGuide) | Angi; HomeGuide |
| Rebar | $0.80–$1.60 per sq ft | Angi |
What moves the price
- Height: taller walls need more material, deeper footings and often engineering.
- Material and finish: stone veneer costs more than plain block or timber.
- Drainage and soil: clay soil and wet seasons make drainage a bigger part of the job. Brentwood's rain is concentrated between October and April (Weather Spark).
- Access: hand work in a tight side yard costs more than equipment access.
- Old wall removal: demolition and haul-off.
- Permits and engineering: see the Brentwood permit rules.
Repair costs
Repairs are priced differently. Angi lists an average repair of about $700 (typical $450–$950), and a full replacement at $6,000–$14,500. See retaining wall repair for the breakdown by problem.
Sources
National cost guides, last checked October 2026:
- HomeGuide — How Much Does a Retaining Wall Cost? (Jan 16, 2026)
- HomeGuide — Concrete Retaining Wall Cost (Dec 23, 2025)
- Angi — How Much Does It Cost to Build a Retaining Wall? (Sep 15, 2026)
- Angi — Retaining Wall Repair Cost (Jul 9, 2026)
- Weather Spark — Average Weather in Brentwood, California (accessed Oct 2026)
Retaining wall cost questions
How much does a 4 ft by 20 ft retaining wall cost?
That is 80 square feet of wall face. At HomeGuide's $35–$65 per square foot average (labor included) the math gives about $2,800–$5,200, though HomeGuide also notes project minimums of $1,500–$3,000 and extras like drainage, footings and permits can add to it. It is an illustration, not a quote.
How much does a 5 ft by 30 ft retaining wall cost?
That is 150 square feet of wall face, which works out to about $5,250–$9,750 at $35–$65 per square foot. A wall that tall may also trigger a permit and engineering in Brentwood, which would be additional costs.
How much does a 100 ft retaining wall cost?
Length alone doesn't set the price; height does. At 4 ft high, 100 ft of wall is 400 square feet, or about $14,000–$26,000 at $35–$65 per square foot. Angi's per-linear-foot range of $40–$360 is wide because it covers walls from about 2 ft to 6 ft or more.
Is a retaining wall cheaper per foot if it's wood?
Wood and timber walls are among the lower-priced materials, at $15–$30 per square foot in both HomeGuide and Angi, but they generally don't last as long as masonry, so compare lifetime cost, not only the installed price.
Are permits and engineering included?
Usually not. Guides list permits at $50–$450 and structural engineering at $350–$2,000 or more, depending on the source. Ask each contractor whether those are in the bid and who pays them.
East Contra Costa communities we cover
Requests come from homeowners across the eastern end of Contra Costa County, along Highway 4 and the Delta.
Get an actual retaining wall quote
Tell us the wall height, length and what is happening. We pass your request to an independent local contractor serving East Contra Costa, who contacts you to look at the project and quote it. There's no cost to send a request.
- Takes about a minute
- No obligation to hire
- Ask for a written, itemized quote