7 min read · updated 2026-04-12
Multigenerational living and the quiet rise of the ADU
Why ADUs have become the dominant housing format for multigenerational families in California — the AARP data, the design choices, and the LA-specific patterns we see.
What 'multigenerational' actually means in 2026
Pew Research's most recent multigenerational household analysis put the share of US adults in multigenerational households at 26% — the highest in over fifty years Pew Research — multigenerational household trends. The Joint Center for Housing Studies at Harvard tracks the same trend in its housing reports Harvard JCHS — State of the Nation's Housing.
In Los Angeles specifically, the share is materially higher. Census ACS microdata shows LA County consistently 5–8 points above the national average U.S. Census ACS data, driven by family structure, immigration history, and the city's housing-cost reality.
Why ADUs fit the multigen pattern
AARP's research on aging in place is the definitive source on why a separate-but-connected unit works so well for multigenerational families: independence with proximity, privacy with safety, autonomy with backup AARP ADU resource center. AARP also publishes design guides for accessible small-footprint units AARP Livable Communities — housing.
The NYT covered the broader cultural shift in detail NYT Real Estate — multigenerational coverage, and the LA Times has tracked the LA-specific multigen housing pattern LA Times — multigen housing coverage.
Design choices that matter most
Single-floor layouts with no thresholds. A 36-inch front door and 32-inch interior doors. A curbless shower with blocking pre-installed for grab bars. A bedroom with a closet large enough for a wheelchair turning radius. Lever handles instead of round knobs. None of these add meaningful cost during construction; all of them are expensive to retrofit.
Dwell has published useful case studies on universal-design ADUs in LA Dwell — universal-design ADU case studies and Fine Homebuilding has good technical coverage on the construction details Fine Homebuilding — accessibility detailing.
The quiet financial logic
If a multigenerational family pools resources, an ADU at $450,000 financed against the main home substitutes for $2,500–$3,500/mo of independent rent or assisted-living cost for an aging parent. Over a 10-year hold, that's $300,000–$420,000 of avoided cost — separate from any value the unit adds to the property at resale.
Curbed LA has documented this pattern in neighborhood reporting Curbed LA — multigen neighborhood reporting.
Frequently asked
- Can my parent live in the ADU rent-free?
- Yes — there's no requirement that an ADU be rented. Many LA families build specifically for family use, with no rental ever planned.
- Should I build a JADU or a detached ADU for an aging parent?
- Detached, almost always. JADUs share interior connections to the main house and don't offer the privacy or independence that aging-in-place benefits from.
- Will building for family use limit future flexibility?
- If you build to universal-design standards (single-floor, accessible shower, wide doors), the unit works equally well as a future rental. Don't over-customize for any one resident.
Sources we cited
- 1.Pew Research — multigenerational household trends — Pew Research Center
- 2.Harvard JCHS — State of the Nation's Housing — Harvard JCHS
- 3.U.S. Census ACS data — U.S. Census Bureau
- 4.AARP ADU resource center — AARP
- 5.AARP Livable Communities — housing — AARP
- 6.NYT Real Estate — multigenerational coverage — The New York Times
- 7.LA Times — multigen housing coverage — Los Angeles Times
- 8.Dwell — universal-design ADU case studies — Dwell
- 9.Fine Homebuilding — accessibility detailing — Fine Homebuilding
- 10.Curbed LA — multigen neighborhood reporting — Curbed Los Angeles
Related areas
Neighborhood guides that pair with this article — local code, lot patterns, and what we've actually built nearby.
San Gabriel Valley — ADU FAQ →
Local rules, costs, and project notes for San Gabriel Valley.
Area overview →San Fernando Valley — ADU FAQ →
Local rules, costs, and project notes for San Fernando Valley.
Area overview →Eastside / NELA — ADU FAQ →
Local rules, costs, and project notes for Eastside / NELA.
Area overview →Orange County — ADU FAQ →
Local rules, costs, and project notes for Orange County.
Area overview →Inland Empire — ADU FAQ →
Local rules, costs, and project notes for Inland Empire.
Area overview →