Basements · Underpinning · Shoring · Excavation
Basement Construction & Excavation Contractor in Los Angeles
A basement is the most valuable square footage you can add in Los Angeles, and the most structurally demanding. SAWA self-performs the entire below-grade scope: shoring and soldier piles, excavation, underpinning of the existing foundation, structural concrete walls and slab, and waterproofing. One crew, one contractor, one schedule.
Licensed, Bonded & Insured · CSLB #1114721 · Pasadena, CA
What's Included
Basements & Excavation: scope of work
- ■New basements under existing homes via underpinning and sequenced excavation
- ■Basements for ground-up homes and hillside residences
- ■Soldier-pile and lagging shoring, tiebacks, and excavation
- ■Structural concrete foundation walls, slabs, and shotcrete
- ■Waterproofing, drainage, sump systems, and backfill
- ■Subterranean garages and below-grade parking structures
How It Works
Our process for basements & excavation.
Feasibility & engineering
We review soils, groundwater, setbacks, and the existing structure with your engineer to confirm the basement is buildable and how.
Shoring & underpinning
Our rigs drill soldier piles and we underpin the existing footings in sequence so the house stays supported throughout.
Excavate & pour
We excavate to depth, place waterproofing, and pour structural walls and slab with our own concrete crews.
Tie into the house
New stairs, framing, and utilities connect the basement to the living space above, ready for finishes.
FAQ
Basements & Excavation: common questions.
Yes. The house is supported while we underpin the existing foundation in short sections, then excavate below and pour new structural walls. It is disruptive but routine for our crews, and it is often the only way to add space on a built-out lot.
In many Southern California jurisdictions, basement area is partially or fully exempt from floor-area calculations, which is why basements are so popular on hillside and view lots. Rules vary by city, so we confirm with the planning department during feasibility.
Cost depends on size, soil, groundwater, access, and whether we are underpinning an existing home or building new. Below-grade work is priced per project after a site visit and review of the soils report, and we give you a firm number before mobilizing.
Shoring, excavation, and concrete for a residential basement typically take three to six months depending on size and underpinning, before interior finishes.
Where We Do This
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Learn more →Start the Conversation
Planning basements & excavation?
Send us the site and the scope. We'll tell you, honestly, what it takes to build it.