How much does a concrete pad cost in Sonoma County?
LawnStarter puts the national average for a concrete slab at $6.60 per square foot, materials and labor included. LawnStarter’s typical range runs $4.34 to $7.73 per square foot. Concrete Network publishes $6.50 to $10.50 per square foot to have a plain slab poured. LawnStarter prices a reinforced slab at $9.29 to $10.04 per square foot.
Those are national published ranges, and California prices run above them. We pour concrete pads and flatwork across Sonoma County, for sheds, workshops, equipment and generators. We also pour dumpster pads for commercial properties. We look at the site before we price a pad, and then you get a written estimate.
What does a concrete pad cost per square foot?
LawnStarter’s typical range is $4.34 to $7.73 per square foot. Concrete Network’s plain slab range runs higher, at $6.50 to $10.50 per square foot. HomeGuide says basic projects can start as low as $4 per square foot. None of these is a Sonoma County price.
| Publisher | What the figure covers | Price per square foot |
|---|---|---|
| LawnStarter | Typical range, installed | $4.34 to $7.73 |
| LawnStarter | National average, materials and labor | $6.60 |
| LawnStarter | 4-inch slab, average | $5.35 |
| LawnStarter | 6-inch slab, average | $6.19 |
| LawnStarter | Reinforced slab | $9.29 to $10.04 |
| Concrete Network | Plain slab, poured | $6.50 to $10.50 |
| HomeGuide | Most basic projects | as low as $4 |
LawnStarter’s reinforced figure is the total with every option in its reinforcement table added. It stacks wire mesh, a vapor barrier, a 6-inch slab, thicker edges and foam insulation on the 4-inch price. On LawnStarter’s numbers, a 6-inch pad with mesh and a vapor barrier works out to $7.04 per square foot. That sits well under the full reinforced range.
What do common pad sizes cost?
A 10 by 12 shed pad comes to $521 to $928 at LawnStarter’s $4.34 to $7.73 per square foot. At LawnStarter’s rates, a 20 by 20 pad comes to $1,736 to $3,092. LawnStarter’s own 8 by 8 example runs $278 to $495.
| Pad size | Square feet | At LawnStarter’s $4.34 to $7.73 per sq ft |
|---|---|---|
| 8 x 8 (LawnStarter’s published row) | 64 | $278 to $495 |
| 8 x 10 | 80 | $347 to $618 |
| 10 x 12 | 120 | $521 to $928 |
| 12 x 16 | 192 | $833 to $1,484 |
| 20 x 20 | 400 | $1,736 to $3,092 |
These totals are LawnStarter’s national rates multiplied out. They add nothing for site work, such as tearing out an old slab or grading a slope. California prices also run higher than these published ranges.
The 10 x 12 size matches the 120 square foot cap on a permit-exempt shed in unincorporated Sonoma County. Generator and equipment pads price the same way. Multiply the pad’s square feet by a published rate, then add for thickness and reinforcement. If the equipment came with installation instructions, have them handy for the estimate.
What adds to the price of a concrete pad?
Thickness and reinforcement raise the price per square foot. In LawnStarter’s figures, going from 4 to 6 inches adds $0.84 per square foot. LawnStarter adds $0.35 for wire mesh and $0.50 for a vapor barrier. Site work then adds its own costs, starting with any old slab that has to come out.
| Add-on | LawnStarter’s added cost per sq ft | What LawnStarter says it does |
|---|---|---|
| Wire mesh | +$0.35 | Reinforces the slab and helps prevent cracking |
| Vapor barrier | +$0.50 | Separates the concrete from moist soil underneath |
| 6 inches instead of 4 | +$0.84 | Increases the slab’s strength |
LawnStarter’s averages on a 10 by 12 pad work out like this:
- 4 inches with no add-ons: about $642
- 4 inches with mesh and a vapor barrier: about $744
- 6 inches with mesh and a vapor barrier: about $845
A commercial dumpster pad has to carry a full bin and the truck that lifts it. Concrete Network notes that commercial applications may require thicker concrete than a home slab.
The concrete itself is priced by the cubic yard. Concrete Network puts the 2025 average ready mix price at $179.95 per cubic yard. A 10 by 12 pad takes about 1.5 cubic yards at 4 inches and about 2.2 at 6 inches. At Concrete Network’s average, that is roughly $270 and $400 of concrete.
Concrete Network also says to factor in the ready mix delivery fee and labor. It notes that some supplier quotes included delivery or short-load fees. A shed pad uses so little concrete that any delivery fee weighs more per square foot.
Removal comes first when an old slab is in the way. HomeGuide puts concrete removal at $3 to $8 per square foot, including disposal. We break out the old concrete and haul it off in our own dump trucks.
Base rock comes next. HomeGuide prices gravel at $1 to $3 per square foot. We spread crushed rock in lifts and compact it with a plate compactor before the forms go in.
A slope adds grading. LawnStarter says it is best to pour concrete on a flat surface. Concrete Network says grading cost depends on the amount of dirt you need to move. On wet or sloped ground, the job starts with grading and drainage for a pad site.
Truck access counts too. Ready mix arrives by truck, so a pad the truck can reach is a simpler pour. A pad behind a fence or down a narrow side yard takes more handling.
Do you need a permit for a concrete pad in Sonoma County?
Usually not for the slab itself in unincorporated Sonoma County. Permit Sonoma’s BPC-005 exempts non-structural slabs and paving on private property from a building permit. The slab must sit outside the county right of way and no more than 30 inches above grade. Inside city limits, the city’s own permit counter sets the rules.
The shed on top is a separate question. BPC-005 limits a permit-exempt tool or storage shed to 120 square feet of floor area. The page lists other conditions too, and it warns that additional permits or review may be required.
Earthwork has its own triggers. Permit Sonoma requires a grading permit when cut or fill exceeds 50 cubic yards or runs deeper than 3 feet. Even digging a 10 by 12 pad a full foot deep moves about 4.4 cubic yards. A pad cut into a hillside can move far more.
We check which rules apply before we quote. State law adds one more step before any digging. Government Code section 4216.2 calls for notice to the regional notification center at least two working days ahead. We make that call to 811 before we dig.
When is the best time to pour a concrete pad in Sonoma County?
June through September is the dry window for a pour. NOAA’s 1991 to 2020 normals at the Petaluma Airport station total 0.43 inches of rain from June through September. December alone averages 5.19 inches.
Dry ground makes base work and pours easier to schedule, and rain in the forecast moves a pour date. Once it is poured, a pad needs time to gain strength before a shed or a machine goes on it. Our guide on how long before driving on new concrete lays out that timeline.
When is a pad really a driveway or a patio?
If the slab will hold parked cars, price it as a driveway. Our guide to concrete driveway prices in Sonoma County covers that job. Our page on concrete driveway installation shows how we build one. For a parking spot on a rural lot, compare gravel driveway costs in Sonoma County too.
If the slab is a place to sit out back, it is a patio. Our concrete patios page covers that work. For stamped patterns and color, read what a stamped concrete patio costs.
What happens at the estimate visit?
We look at the site and check the ground and the grade. We also check how close the concrete truck can get and where the forms will sit. Then you get a written estimate for the pad.
Rich’s Paving is a third generation family paving company, paving Sonoma County since 1988. Our page on concrete flatwork for homes and businesses shows the rest of what we pour. Give us a call when you want an estimate for your pad.