Slab foundation building in Sunnyvale CA - built for the soil under your house

Most people who call me are planning a new home, an addition or an accessory building, and they want to know what the foundation will take before the plans go much further. The price turns mostly on the size of the slab and on the soil under it, because on expansive clay, the kind that swells when it's wet and shrinks as it dries, engineers don't consider a plain 4-inch pad enough, and a post-tensioned slab, with steel cables run through it and tightened after the pour, is often the cost-efficient answer. The schedule usually depends on how soon the soils report and the engineer's plans are ready, and on the city's review, so those come first. If your addition only needs concrete footings rather than a full slab, we build those too. After I visit your lot, you get the scope and the price in writing.

I ask for your soils report early, since it shapes how the slab should be designed, and we build to the engineer's plans from there. Our crew digs out to firm ground and packs the subgrade, the soil and base the slab sits on, so it doesn't settle later the way loose fill does. Before any concrete arrives we check where the water runs on your lot, so the ground falls away from the building and not toward it. Then we set the forms, place the rebar, the steel bars that hold the concrete together as it carries weight, or the post-tensioning cables the plans call for, and we schedule the pour for the cooler part of the day so the top doesn't dry too fast and turn weak and dusty. Where the design calls for control joints, shallow cuts that give the concrete a chosen place to crack, we cut them on time, and we keep the slab damp while it cures, which is the wait that lets it gain its strength. I'll also be honest with you that a slab can show some cracking, so we talk through how we plan for it before the pour, not after. If a budget needs trimming, I'd rather trim almost anything than the base, because it's the one part you can't fix once a house is standing on it.

Foundations often come with other concrete work around them. When a building needs a deeper or raised design instead of a slab, that's our foundation installation work, and when a property owner or builder needs paving around a new building, our concrete parking lot building starts with the same packed base and drainage check.

In Sunnyvale, building plans go through the city's Permit Center, and the city asks first-time applicants to call and find out whether their project will need plan review. Every project has different requirements, so we don't guess about yours. When the job needs a permit, we handle the application and the inspections with the city and keep you informed, and if it isn't clear, we check with the permit office before we start. The city runs its permits online, where documents, comments and inspections are handled, so you can follow along as it moves.

The state also maps Liquefaction Zones, areas where the ground can lose its strength in an earthquake, and cities must use them when they issue permits, so on those sites the foundation soil has to be investigated for buildings people live or work in. Between that and the clay some lots have, the soil question comes before anything else, and we see the same question on jobs in Santa Clara and Mountain View.