Slab foundation building in Piedmont CA - a slab designed for the ground under it
Planning a new home, addition or rebuild on shifting East Bay soil? We plan the slab around your ground, then pour it right.
- Licensed and insured.
- Free in-person estimates.
- Expect a reply within 1 business day.
What goes into building a slab foundation in Piedmont?
A slab foundation is a concrete base poured on prepared ground to carry your house, and when we build one in Piedmont, we plan the design around your soil first, then form, pour and finish the slab.
Most people who call about a slab are building a new house, an addition or a rebuild, and they want a foundation that won't give them trouble later. The price moves with the size of the footprint, the thickness and steel your soil calls for, how much digging and base work the lot needs, and how easily a truck can reach the pour on a steep street, while the schedule turns mostly on the design and the city's review rather than the days we spend pouring. If you only need support for a deck or a small structure, concrete footings may suit you better, and I'll say so plainly. Once I've seen the lot, the written estimate gives you the figure for your own slab.
How we build a slab foundation
The first thing I ask for is your plans and any soil or survey report, because the slab design belongs in that first conversation and not after the forms are up. From there our crew digs down to the subgrade, the native ground the slab sits on, and packs a firm base on it instead of raking loose dirt level, then sets the forms and checks that the finished slab will shed water away from the house. We place the rebar, the steel bars that hold the concrete together and keep any cracks tight, and we time the pour for the cooler part of the day so the top doesn't dry too fast and turn weak and dusty. After finishing, the slab cures, slowly hardening and gaining strength, before anyone builds on it. The base is hidden the day we pour and it's the first thing people want to trim from a budget, but I won't cut it, because in a kitchen a plate is only as good as the setup behind it, and once concrete is poured there's no taking it back. I'll also tell you honestly before we start that a slab can show some small movement over the years.
Some projects need more than one kind of foundation. Where part of the house sits on a raised floor or perimeter walls, we handle that as foundation installation alongside the slab so the two meet properly. If the property also needs a large paved area for cars, concrete parking lot building uses the same dig-out and base work we do under a slab.
Conventionally reinforced slab
This is a slab with rebar set through it, and it suits ground that a soil report shows to be fairly stable and a design that's straightforward. Your engineer's plans set its thickness and steel, and we build to them.
Post-tensioned slab
Steel cables run through this slab are tightened after the pour, keeping the concrete under a built-in squeeze that resists the pull of moving soil better than a slab without it. The industry group for this method calls it cost-efficient for homes on soil that shrinks and swells, so if your report shows that kind of ground, it's worth asking about.
Slab foundation building in Piedmont: the permit and the ground
The City of Piedmont issues building permits through its online permit system, and most construction projects and repairs there need one. We handle the application and the paperwork, tell you up front which office it goes through, and if anything about your job isn't clear, we check with the city before we start. The city also requires anyone doing business in Piedmont to hold a city business license.
On a Piedmont lot, the ground decides a good deal about the slab. A regional hazard map shows liquefaction risk in Piedmont for an earthquake on the Hayward fault, which is when wet sand turns almost liquid under strong shaking, but the map is area-wide and ground can change abruptly from one lot to the next, so borings at your site are what actually address it. State law also requires a site-specific study by licensed geologists or engineers before permits for most occupied buildings in the zones it maps for closer study, though single family frame homes up to two stories outside developments of four or more units are exempt, and local agencies can be stricter. That's why I ask for soil reports early. We're based in Piedmont and work in Oakland, Berkeley, Alameda and other cities around the East Bay, and we meet the same hillside lots, tight access and older homes on jobs in Oakland and Berkeley.
Why Piedmont homeowners call Piedmont Advanced Concrete for slab work
I come out to every job
I look at every job myself and give the estimate, then I work on site with our crew, who handle the forming, pouring and finishing. You deal with the same person from the first visit to the final walk-through, so nothing gets lost between the estimate and the pour.
Building in Piedmont since 2020
I learned the trade on a finishing crew here in the East Bay and started this business in Piedmont in 2020, so we've been at it six years. We're best known for careful flatwork and the foundation work older homes here need, and a slab asks for that same care.
Licensed and insured on site
We're licensed and insured, and I'm glad to show you the paperwork when I come out. It's a fair thing to check on anyone who'll be working on the base of your house.
On a slab, what you can't see after the pour matters most, so I'd like to start with your plans and your ground. Reach us through our contact page or call (510) 738-1848, and thank you for considering us.
Request a quoteGet a written estimate for your slab foundation
We reply to every call and message within one business day to set up a visit. I come out myself, measure, look at access and send you a written estimate. The estimate is free and comes with no obligation.
What happens after you call about a slab foundation in Piedmont?
Call or send the form
Thank you for reaching out. We'll set up a time for me to visit, and it helps to tell us what you're building and where it sits on the lot.
I visit and write it up
I look at the site and how we'll get equipment to it, listen to what you have in mind, and send you a written estimate. You'll see the figure for your own slab on paper before you decide anything.
We line up the city review
Once you're ready, we take care of the city steps, and the city reviews small, simple permits in about 2 to 4 weeks, while a larger, more complex project takes about 5 to 8 weeks for a first review. It's worth building that wait into your schedule before the work starts.
We prep, pour and walk it
Our crew preps the site, pours and finishes the slab, then cleans up. I walk the finished job with you so you can look it over and ask anything before we leave.
Frequently asked questions
How much does a slab foundation cost in Piedmont, CA?
A concrete slab foundation in San Francisco usually costs about $7 to $18 per square foot, which is the nearest market figure we have and not our own price. Where a Piedmont job lands depends on the lot and the design, and your own figure comes from the written estimate after I've seen the site and your plans.
How long does it take to get a slab foundation built?
Usually the planning and the city's review take longer than the concrete work, so most of the wait comes before we dig. The review times are in the steps above, and after the pour the slab needs time to cure before framing goes on it, so plan for both.
Will a new slab foundation move over time?
Some movement is normal. Engineers report that even a well designed, well built slab on soil that shrinks and swells can show cosmetic flaws, small marks in how it looks, and a slab with no movement at all would cost too much and likely couldn't be built. That's why I talk through the soil and the design with you before we start.
Who can build my slab foundation and pull the permit in California?
In California a building permit goes only to a properly licensed California contractor or to a property owner acting legally as an owner-builder. The state's license class for concrete contractors covers forming, pouring, placing and finishing concrete, and if a B general contractor signs the main contract, the state licensing board suggests asking whether it holds that specialty class or subcontracts the work to a licensed specialty contractor.
Do I need a vapor barrier under a slab foundation?
It's worth raising with your designer, because some designers always put a vapor barrier, a plastic sheet that keeps ground moisture from wicking up, under the slab. Their reasoning is that it costs little while the slab is being built, and moisture problems are hard to fix afterward.
What causes a new concrete slab to crack?
Concrete shrinks as it dries and the ground under it moves, so some cracking is expected, and the trouble starts when cracks land where nobody planned. On flat slabs we cut control joints, shallow grooves that give the concrete a chosen place to crack, and cutting them on time matters as much as cutting them at all.
Related foundation and concrete work
Foundation installation
For homes or additions built over a crawlspace or on perimeter walls, this covers the footings and stem walls that hold the frame up off the ground.
Concrete parking lot building
If your property needs room for several cars, a shared drive or a small business lot, we build it on a dug-out, packed base so it stands up to steady traffic.
Piedmont, CA
Send your plans for a slab estimate
Having the property address, any plans and any soil or survey reports ready when you call (510) 738-1848 or send the form lets me come to the visit already knowing what your slab has to carry.