Build a realistic week-by-week schedule from engineering through final inspection, using typical Bay Area plan-check and construction durations for your city and scope.
Every result is a planning estimate, not a quote or an engineering determination. Real pricing depends on soil conditions, access, existing structure, engineering requirements, and your jurisdiction’s current fee schedule. For structural questions we coordinate with a licensed engineer — we do not perform engineering ourselves. Get a site-specific estimate before committing to a budget.
Most homeowners budget for the pour and forget the paperwork. In Santa Clara County the office half of the job is usually longer than the field half. A straightforward ADU foundation might take five or six weeks of actual site work, but engineering plus plan check can add two to four months before a single form board goes up.
Three things move the needle more than anything else:
Inspection scheduling is the quiet one. Pre-pour footing and rebar inspection has to happen before concrete arrives, and if the inspector books out three days, the ready-mix truck moves with them. Rain is the other. From roughly November through March, Bay Area pours get pushed for wet subgrade and for the cure window, and a single storm cycle can cost a week even after the sky clears.
Utility locates, tree-protection requirements, and neighbor notification in the smaller cities can also add time that never shows up on a construction calendar. If your project touches a detached ADU or a room addition, planning review runs in parallel with building plan check and often becomes the long pole.
The practical takeaway: start engineering earlier than feels necessary, submit a complete set the first time, and keep the construction window flexible by a couple of weeks in either direction. Schedules that assume everything lands on the early end are the ones that disappoint.
It reflects typical durations we see across Santa Clara County and nearby cities, but it is a planning tool, not a commitment. Your actual schedule depends on submittal quality, city backlog, soil conditions, weather, and inspector availability. We give firm scheduling windows only after a site visit and an approved plan set.
No, and you should be skeptical of anyone who does. Plan check is controlled entirely by the city. We can tell you what is typical for your jurisdiction, prepare a complete submittal, and respond quickly to corrections, but approval dates are not ours to promise.
The pour itself is often a single morning. What follows is chemistry. Forms usually come off around 7 days, and concrete reaches full design strength near 28 days. Loading or backfilling too early risks cracking, so the cure window is built into every honest schedule.
Yes, and they usually do. Material ordering and crew scheduling start while plan check is still running, and site prep can begin as soon as the permit issues. That is why the total is presented as a calendar range rather than a strict sum of each step.
Often yes for anything structural. We are a foundation and concrete contractor, not an engineering firm, so when a stamped design is required we coordinate with a licensed engineer rather than making that determination ourselves.
Tell us what you're building — a new home, an ADU, an addition — and we'll get back to you with next steps, usually within one business day.
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