Building a home or addition on a slab? We keep the plumber, electrician and inspector in order, then pour a level foundation you can build on.
Slab foundation building in Tiburon means forming, pouring and finishing a concrete slab right on the ground so it becomes your home's foundation. The pipes, wiring and inspections under it get finished before any concrete goes in.
Most of the slab calls we get start with plans for a new home, an addition or a separate building out back. The slab goes in first and gets covered up fast. That's why I put most of my attention on the subgrade, the packed ground the slab sits on, and on where water will run once the walls are up.
The price mostly follows the size and thickness of the slab and how much digging and base it takes to reach firm ground. It also follows how much steel goes in and whether the plans call for a post-tensioned slab, one squeezed tight by steel cables. Getting a concrete truck and pump close to your site matters too. My written estimate spells out what's included on your job.
The schedule depends less on pour day than on what comes before it. Tiburon's review and permit come first. Then the plumber and electrician finish what runs under the slab and it gets inspected, and only after that do we set the pour date. Where your project stands in that line matters more to timing than the concrete does.
These are the parts you won't see once the concrete is down. They're also where a slab usually goes wrong, so they're where I spend the most time before we pour.
A slab only stays as flat as what's under it. We dig down to firm ground and pack the base instead of raking loose dirt level, because loose fill settles over time and the slab settles right along with it. This step is the easiest one to skimp on, since nobody sees it after day one.
Before we set forms, I look at where rain runs across your lot and where it'll go once there's a roof and gutters. The finished ground around the slab should fall away from the house so water doesn't pool against the edge and soak in under it.
When your plans call for a vapor retarder, a plastic sheet that keeps ground moisture from wicking up into your floors, it only works if its seams and the openings around pipes are sealed. It also has to stay intact while other trades work over it, so we look it over again right before the pour.
Concrete shrinks as it hardens, so a fine crack or two is normal. Rebar, the steel grid inside, holds a crack tight. Curing, which means keeping the slab damp through its first days, lets the surface reach full strength. We plan pours for the cooler part of the day because midday heat can leave a weak, dusty top.
Here's how a slab job runs with us, from the first call to the walk-through. Most of the work is in getting the order right before any concrete shows up.
Call (415) 429-4397 or send a message through the form. Let us know whether it's a new home, an addition or a separate building and where your plans and approvals stand, so I know what to look for on the visit.
I come out myself, look at the site, measure and ask how you plan to use the building. Then I write up an estimate in plain words that spells out what's included.
Once you're ready, we sort out what Tiburon or the county asks for and set the order. The plumber and electrician finish their under-slab work and the inspector signs off. Then we prep the base, pour and finish.
When the slab's finished, we walk it with you and answer any questions that are left. We also talk about keeping traffic off it while it cures so it's ready when your framer arrives.
A slab foundation takes several trades working in order. The plumber runs drain and supply lines under it, the electrician sets any conduit, and the inspector looks at all of it before we pour. Once the concrete's in, nobody can reach those pipes without cutting. We keep that order clear for you and set the pour date around it, so nobody shows up early or waits on someone else.
If the budget gets tight, the base is usually the first thing people want to cut, because it's buried by the end of day one. I'd rather trim the finish than the base. A plain slab on well-packed ground stays flat under your floors. A nicely finished slab on loose fill can sink and crack, however good it looked on pour day.
Some plans call for foundation work beyond the slab itself, and our foundation installation service handles that. The same base habits carry over to bigger flatwork, our word for any concrete laid flat on the ground. Under a concrete parking lot, packed ground and good drainage matter just as much with cars on it every day.
Where the slab becomes your floor or goes under tile, wood or carpet, we finish it smooth with a steel trowel so the flooring lies flat. It's the usual choice for living space.
Any part that stays outdoors, like a porch edge or a garage apron, usually gets a broom finish. That's a light brushed texture that gives shoes and tires grip when it's wet.
We respond within 1 business day, and the on-site estimate is free, with no pressure and no obligation. After you send the form, I'll set a time to come out, look at the site, ask how you plan to use the building and write up an estimate in plain words.
(415) 429-4397The Town of Tiburon generally requires Design Review approval for all new homes, any addition and all accessory structures, so a slab for one of those is part of a project Tiburon reviews first. A building permit has to be granted before any demolition or construction, and Tiburon's Building Division inspects the work against the approved plans. We find out what your job needs, help with the paperwork and wait for the permit to be in hand before we start.
Permit applicants in Tiburon also have to track a required share of the project's discards and send it to recycling or reuse instead of the dump. We plan from the start where leftover form boards, scrap steel and any old concrete will go. On undeveloped land where the state has found that weak soil or rock is likely, a site study by a licensed engineering geologist or civil engineer may be required before most structures are permitted.
We build slabs in Mill Valley and Sausalito too, and the order of the job stays the same. What each city's building office asks for can differ, so I check yours on the visit instead of assuming it matches Tiburon.
I started this business in Tiburon in 2020. I taught myself concrete on small jobs at my own place and learned the rest beside people who'd been pouring for years. I still come out to look at each job myself and write the estimate, and I'm on site with our crew while the work gets done.
We're fully licensed and insured. Our work is backed by our satisfaction guarantee. Before anything gets poured, I'll walk you through what we're doing and why. I'd rather answer a question twice now than leave you wondering about it after the slab is down.
If you're planning a home, an addition or a backyard building on a slab, call (415) 429-4397 or send us a message. I'll come out and take a look.
When your plans call for foundation work beyond a slab on the ground, this service covers the rest of the structure your house will stand on.
Need to pave a shared lot, a long apron or room for several cars? We build those on the same packed base and planned drainage a slab gets.
We're based in Tiburon and work in cities across Marin and nearby, from Novato down to Sausalito and over to Richmond. The cities listed here are some of the places we work, not the only ones.
A reinforced concrete slab in the Bay Area usually costs about $9 to $16 per square foot. That's the going rate across the area, not our price. For your own figure, I'll come out, measure and write up an estimate.
Usually not the day after the pour, because the slab needs time to cure and gain strength before walls and lumber go on it. How long depends on the mix, the weather and the load. I'll give you a realistic day for your framer before we pour rather than guess now.
Have the project type, a rough idea of the slab's size and any approved plans ready. If your project is still in Design Review, tell me where it stands. That sets how soon we can schedule and what I need to look for on the site.
Depending on the project, Tiburon's required inspections may include a preliminary inspection before the permit is issued, a footing and foundation inspection, and a concrete slab and under-floor inspection. Tiburon counts a project as complete only after its final inspection, so ask us when that visit is planned and we'll keep you posted.
A post-tensioning trade group says these slabs suit home foundations on soils that shrink and swell, because the steel cables hold the concrete under compression and that resists the ground's pull. The same group says they reduce cracking and keep cracks tight. If your slab is post-tensioned, tell any later trade before they drill so they can locate the cables first.
Yes. Forming, pouring, placing and finishing flat concrete work falls under the state's concrete contractor classification. State law exempts minor work from licensing only when the full contract price is less than $500, so ask any contractor you're comparing whether they hold that license.
The pour date gets set around the plumber, electrician and inspector, so calling (415) 429-4397 or using the form while your plans are still in review gives us time to line them up.
