Building Attached ADUs in Concord: A Sacramento Contractor's Honest Take
We build attached accessory dwelling units in Concord — the kind that share one wall with your house and add a full second home with its own door, kitchen, and bath. Future Generation Construction is a design-build outfit based in Sacramento, license #1119373, and we drive into the East Bay for projects worth the trip. This page is the straight version: what an attached ADU is, why the Concord math differs so sharply from inland California, and the parts of the build that people get wrong.
Why attached makes sense in Concord
Concord is the largest city in Contra Costa County, and it's a more reasonable place to build than a lot of the East Bay — more affordable than Walnut Creek right next door, mostly flat, with sensible tract lots instead of impossible hillsides. That said, it's still the Bay Area. Land value is high, the city's permitting is slower and pricier than what we deal with around Sacramento, and the ground wants seismic engineering because of the faults under the region. All of that pushes the cost of a freestanding detached ADU higher than first-time owners expect.
An attached ADU sidesteps a chunk of that. You're sharing a wall that already stands, which means less structure to build. You're tapping utilities already at the house, which means less trenching across the yard. On a tighter Concord parcel — and the older tracts run the gamut from roomy to snug — the attached unit fits where a detached one doesn't, because the setbacks leave room for an extension off the back or side but not for a standalone building with its own four walls.