Foundation installation in Gardena CA - a base that suits your lot and soil

A slab usually suits a flat lot, and a crawl space usually suits uneven ground. A slab controls moisture well but fits a sloped lot poorly, while a crawl space handles uneven ground but tends toward moisture problems, so it needs a plan for that. We look at how your lot sits and what the site study says before anyone settles on a slab or a raised foundation.

Soil movement is a common cause, especially expansive soil, which lifts the ground when it's wet and lets it settle when it dries. Research finds that movement often goes past what a house can take, and cracked floors and walls are the usual result. Whether your lot has that kind of soil is something a site study answers, so it belongs at the start of planning, not after the pour.

The city requires an application and plans, sent as PDF files, before any grading or building work can begin. Many projects need those plans drawn by a licensed architect or engineer, and the city checks them against zoning and the Building Code, with a focus on structure and earthquake safety. If your lot falls in one of the state's mapped liquefaction zones, where ground can turn soft and lose strength in a strong quake, the project may have to study and reduce that hazard during permitting. We check with the city for your address, and when the job needs a permit, we pull it and line up the inspections before we pour.

The state's contractor license board defines a concrete contractor as one who forms, pours, places, finishes and installs concrete, so that's the license to look for on your foundation. If a general building contractor is running your build, ask who's doing the concrete, because a general contractor can take that work on alone only with the right license or a licensed concrete subcontractor, unless the job covers at least two unrelated trades besides framing or carpentry.

The cost comes down to the foundation type, its size and what your lot and soil need, so the number comes from measuring your site. A slab, a crawl space and a post-tensioned slab each price differently, and a sloped lot, extra grading, a site study or drawn plans all add to it. Your written estimate spells out the work, so you can see what you're paying for.

Most of the wait usually comes before the pour, in plan review and permitting, and the review times are in the steps below. The design matters too, because a post-tensioned slab has fewer pieces to handle and less concrete to place, so it can often go in faster than one reinforced with rebar or wire mesh. We set the schedule once the permit is in hand.