The hiring sequence that actually protects you is short. Get at least three written scopes. Check each license yourself at cslb.ca.gov. Confirm who pulls the permit, what drainage is in the bid, and that any home-improvement-contract deposit is no more than 10 percent of the contract or $1,000, whichever is less. Then pick the crew whose scope you understand. Wall Pro SD matches you with licensed independent contractors. We do not hold a license and we do not build the wall.
Why the hiring decision matters more for retaining walls than most projects
A retaining wall that is built incorrectly does not always fail on day one. Drainage or design defects can show later. By then the original crew may be hard to reach. The repair still sits with the owner. That is a reason to check license, scope, and drainage in writing before anyone digs.
This is not a reason to be paralyzed, but it is a reason to be deliberate about who builds your wall. The characteristics of a good retaining wall contractor are observable before the job starts, and the warning signs of a shortcut contractor are also observable if you know what to look for.
What license a retaining wall contractor needs in California
CSLB publishes descriptions of what each license classification covers, not a rule assigning one classification to every retaining wall. The C-29 masonry description covers concrete units, block and stone used in structural load-bearing walls. The C-8 concrete description covers formed, poured and finished concrete work. Which one fits depends on how your wall will actually be built, so ask each bidder which classification covers their proposed scope and check that license yourself.
Verify any contractor’s license before signing a contract. The California State License Board Check A License tool lets you search by contractor name, company name, or license number. Confirm the license is current and that the classification matches the proposed work. Read what the record actually shows. Do not assume it lists every complaint.
Never hire a retaining wall contractor who cannot provide a California license number. Ask who will be named on the permit. An unlicensed crew cannot be the contractor of record on a permitted job.
Questions to ask before hiring
These questions are worth asking directly, before getting a quote.
Do you pull the permit when the wall needs one? If a permit is required, the bid should name who applies. A contractor who says a required permit is optional is a red flag. Permitted walls get inspections. Those inspections create a record of the work.
Who designs the wall when a City of San Diego permit is required? Some walls inside City limits can use the standard masonry drawings in Information Bulletin 221, only within that bulletin’s height, soil, surcharge, and geologic limits. A wall outside those design criteria needs a California-licensed civil engineer, structural engineer, or architect. Other cities and the County use their own rules. Ask which path is in the bid.
What is behind the wall in your scope? The answer should specifically describe drain rock (not native soil), perforated drain pipe, and where the water exits. If the contractor says drainage is extra or does not describe it specifically, drainage is likely being underbuilt.
Have you built walls for similar loads and access? Ask about retained height, drainage, and tight lots. Do not treat a city name as a soil type. Expansive soil is a site finding. The City’s standard masonry designs may not retain it.
How to compare bids
A complete retaining wall bid should specify at minimum: wall material and manufacturer, wall length and height, whether drain rock and perforated pipe are included, whether engineering and permit are included (or explicitly excluded), backfill material and compaction specification, and any demolition of existing walls.
Low bids that leave out drainage, use vague language about materials, or exclude permits are not actually comparable to bids that include all of those items. Before comparing price, make sure you are comparing the same scope.
Some contractors give per-linear-foot prices and some give lump sums. Per-linear-foot prices are easier to compare across bids if the wall length and height are consistent. Make sure you know what the total linear footage is and what height each bidder is pricing.
Get more than one written scope for the same dimensions and inclusions. Check licenses yourself. A conversation with a recent customer can help, but only if you asked that contractor for the contact. We do not publish testimonials.
Red flags before the job starts
Demanding full payment upfront. California law limits deposit requirements for home improvement contracts to 10% of the contract price or $1,000, whichever is less. A contractor asking for more than that upfront is not operating within the law.
No written contract. Get the scope, the price and the schedule in writing before any work starts. A contractor who wants to work on a handshake is removing your only record of what was agreed, and a retaining wall is not the job to find that out on.
No license or insurance documentation. Ask for the license number and verify it on cslb.ca.gov. Ask for a certificate of insurance showing general liability coverage. Both should be provided without hesitation.
Offering to do the work without permits to save you money. On a permitted project, this offer saves the contractor time and saves you the permit fee, but it eliminates the inspection record that documents the work was done correctly. That documentation is worth significantly more than the permit fee.
What Wall Pro SD does
Wall Pro SD is a referral service. We connect San Diego homeowners with licensed, experienced local retaining wall contractors across the county, from Oceanside and Encinitas in the north to Chula Vista and National City in the south, and inland to El Cajon, La Mesa, and Santee.
We do not hold a contractor’s license, and we do not perform the work. What we do is connect you with licensed contractors who have local experience and can handle the project from permit coordination through final inspection.
Call (858) 400-4639 to get connected with a local retaining wall crew that can come out to your property, measure the site, and give you a real quote.
For help understanding what type of wall fits your project, see our concrete block retaining walls and retaining wall inspection pages.