Foundations

Berkeley Backyard Detached ADU

Berkeley, CA

Project Type
ADU Foundation
Project Year
2026
Structure
Detached backyard ADU
Finish
Steel-troweled slab
Top-down view of the finished ADU slab still in its forms, anchor bolts set and the stepped bump-out at one corner — Berkeley Backyard Detached ADU, Berkeley, CA
Overview

New Edge Concrete built the foundation for this detached backyard ADU in Berkeley in 2026, working with general contractor GR Innovative Builders. It is a classic Berkeley infill lot — neighbors on three sides and the only way in is down the side of the existing house — so the footprint was excavated and the spoils moved out through that narrow side yard before any concrete work began. We set the perimeter forms, laid a compacted base and vapor barrier under a full two-way rebar mat, and worked the underslab plumbing and electrical stub-ups in with the GC ahead of the pour. The slab went in by pump in a single day and was steel-troweled flat, with a thickened perimeter, anchor bolts set wet, and a stepped bump-out and short stem wall at the back corner for the ADU’s utility wall.

General ContractorGR Innovative Builders

Scope of work

  • Tight-access backyard excavation
  • Compacted base & vapor barrier
  • Full two-way rebar mat
  • Underslab plumbing & electrical coordination
  • Formed slab with thickened perimeter
  • Pumped pour & steel-trowel finish

The finished result

During the build

Excavation, forming, reinforcement, and the pour — the work behind the finish.