Slab foundation building in Duarte CA - even support under the whole house

An installed slab foundation of 800 to 1,200 square feet in the Los Angeles area usually costs about $4,000 to $15,000 per job. That's the going range across the area, not our price, and a simpler pad on clean, firm ground sits toward the low end while heavy ground work or a more involved slab type pushes it up. I write up your own figure after I've seen the lot.

Yes, Duarte requires a building permit to build any building or structure, and plans go in at the Community Development Department counter. The city can issue it to a contractor with a Class B general building license, or to a homeowner improving their own principal residence who meets the owner-builder declaration's conditions. Plumbing, sewer, electrical, drainage, grading and other trade work tied to the job each need their own permit. We're fully licensed and insured, and we tell you up front who is handling each piece.

Probably a little, and that's normal for concrete, not a sign something went wrong. Slab construction guidance says getting rid of cracks and curling, the slight lift at edges and corners, entirely isn't realistic even with advanced design and building. I'd rather tell you now than have it surprise you, and even ground prep is the best way I know to keep it to the small, ordinary kind.

A vapor retarder, a plastic sheet laid under the concrete, is the usual answer. One vapor retarder maker says a properly installed one reduces or eliminates indoor moisture problems, including damaged floor coverings and mold or mildew that hurts indoor air. If you're planning wood, vinyl or carpet over the slab, tell me at the estimate so we plan for it.

Ask whether a post-tensioned slab suits your lot, because a post-tensioning trade group calls them a cost-efficient, high-performance choice for home foundations on ground that shrinks and swells. In a post-tensioned slab, steel cables run through the concrete and get pulled tight after the pour. I won't guess what your Duarte lot is like from the curb, so we talk through which slab type fits once I've seen it.

The state's Seismic Hazard Zone Map shows the areas where liquefaction, wet ground losing its strength, and landslides may happen in a strong earthquake. If your lot sits inside one of those zones, you may be required to investigate the hazard and deal with it during the city's permitting. Whether a particular lot is mapped in one is something we check before anything is scheduled, along with the rest of what the city needs.