This page covers the choices you make before the pour: the material, the thickness, the steel, the finish and what goes under the slab. Each answer is written for Vacaville's hot dry summers and clay ground.
The dollar figures here are national ranges that HomeGuide published for 2026. They are not quotes from us. Solano County labor rates, the price of ready-mix on the day and what we find on your lot all shift the real number. Last checked October 2026.
Concrete or asphalt for a driveway?
Concrete suits Vacaville heat better. Asphalt softens on days near 100 degrees and can mark under tires and kickstands. Concrete stays hard, reflects more sun and lasts longer with less upkeep. Asphalt costs less to start: $5 to $12 or more per square foot nationally against $6 to $15 for a concrete driveway, and a 20x20 asphalt drive runs $2,000 to $4,800. Asphalt also needs resealing every few years. For a long rural drive in Allendale or Elmira, asphalt or a mix of the two can make sense on cost.
Poured concrete or pavers?
Poured concrete costs less and goes in faster. Pavers cost $10 to $17 per square foot installed nationally, with a 20x20 patio at $3,800 to $6,800, against $4 to $12 for a plain concrete patio. Pavers have one clear advantage on moving clay: they flex instead of cracking, and a section can be lifted and relaid. Their weak points are weeds in the joints and edges that spread if the border is poor. Stamped concrete sits between the two on looks and price.
How thick should a concrete driveway be?
Four inches is the usual minimum for cars and light pickups, and 5 to 6 inches is better where an RV, a boat trailer or a work truck will park. Thicker edges help where vehicles cross onto the slab. On Vacaville clay, the compacted rock under the slab matters as much as the slab thickness itself.
Do I need rebar or wire mesh?
On expansive clay we recommend steel in driveways and most patios. Rebar or wire mesh does not stop concrete cracking. It holds the pieces tight together so a crack stays a hairline and the two sides stay level. Rebar on a grid, held up on supports so it sits in the middle of the slab, does this better than mesh that ends up on the bottom. Fiber in the mix helps with surface cracking but does not replace steel.
What PSI concrete do I need?
For most home driveways and patios a mix in the range of 2,500 to 3,000 PSI is common in mild climates, and 3,500 to 4,000 PSI is used for heavier loads. PSI is the crushing strength after 28 days. Cold regions call for higher strength and air-entrained mixes to resist freezing, which is less of a concern here. A building slab uses whatever the engineer or the code specifies. The quote should state the PSI.
Is stamped concrete worth it?
It is worth it if you want the look of stone or brick in one slab and accept the upkeep. Stamped concrete costs $8 to $19 per square foot nationally, roughly double plain. It needs resealing, the strong sun here fades color over time, and repairs rarely match perfectly. For a back patio you look at every day, many owners think it is money well spent. For a side yard or a utility pad, plain broom finish is the sensible pick.
Should I seal new concrete, and when?
You do not have to seal plain concrete in this climate, but sealing helps against oil, leaf stains and water getting into the surface. Stamped and colored concrete should always be sealed. When to seal new concrete depends on the product: many sealers go on after about 28 days, once the slab has cured and dried, and some cure-and-seal products go on the day of the pour. Sealing costs $1 to $3 per square foot nationally for cleaning and sealing, or $575 to $1,700 for a 2-car driveway.
How often does concrete need sealing? A film-forming sealer on stamped work usually needs redoing every two to three years in full sun. A penetrating sealer on plain concrete lasts longer, often five years or more. When water stops beading and starts to darken the surface, it is time.
Broom finish or smooth finish?
Broom finish for anything outdoors. The fine ridges give grip when the slab is wet from rain, sprinklers or a hose. A smooth steel-trowel finish is for garage floors, shops and indoor slabs, and it is slick when wet. Exposed aggregate and a light salt finish are other outdoor choices with good grip.
What finish works for a steep driveway? A heavy broom finish dragged across the slope, or grooves pressed across it, so tires and shoes have something to bite. Steep drives are common in the hills on the west side of Vacaville and in Vallejo and Benicia. Avoid smooth stamped patterns and glossy sealers on a slope.
What does a hot tub pad need?
A flat, level slab at least 4 inches thick with steel, on a compacted base, and often thicker for a large tub. A filled hot tub with people in it can weigh several thousand pounds, so check the maker's stated load. This is one of the few outdoor slabs poured dead level. Plan the electrical conduit before the pour, and keep the pad clear of the house drainage path.
What does a shop slab for a vehicle lift or heavy equipment need?
It needs the thickness and strength the lift maker specifies, which is often more than a standard 4-inch floor, with thickened areas under the posts. A slab for a vehicle lift or heavy equipment should be designed around the anchor bolt requirements before it is poured, because adding thickness later means cutting out and repouring. A shop building slab also needs footings and a permit.
Do I need gravel under a slab, and a vapor barrier?
Yes to the rock on our soil. A layer of compacted crushed rock or gravel under the slab gives even support and a break between the concrete and the clay that swells and shrinks. A vapor barrier is a plastic sheet under the slab that stops ground moisture rising through it. It is needed under enclosed, finished or heated space such as a house, a garage conversion or a shop with coated floors. It is normally left out under outdoor patios and driveways.
What does a pad that takes delivery trucks need?
A thicker slab, more steel and a stronger base than a car driveway. A loaded delivery truck or a garbage truck puts several times the weight of a car on each wheel. Six inches or more with rebar on a thick compacted base is typical, with joints placed so wheels do not run along a free edge. Tell us exactly which vehicles will use it.
My pool deck is worn. Resurface, pavers or poured concrete?
Resurface if the pool deck is solid and only looks tired. Pool deck resurfacing costs $3 to $6 per square foot nationally. Choose pavers or new poured concrete if the deck has sunk, tilted toward the pool or broken up. Whatever you pick, use a finish with grip and a light color, because dark decks get too hot for bare feet in a Vacaville summer.
What goes between a patio and the house?
An isolation joint, sometimes called an expansion joint. It is a strip of compressible material placed against the foundation before the pour, so the patio and the house can move separately. Without it, a patio on swelling clay pushes on the house or cracks along the wall. The slab should also slope away from the house and stay below the weep screed or siding.
To get an actual price for your job, ask for a free on-site estimate. We measure, look at the soil and the access, and put the quote in writing. Call (707) 385-5848 or text a photo of the area.