Multigenerational living

ADU / In-Law Suite Cost Calculator

Estimate the order of magnitude for a small independent or semi-independent living space.

Planning inputsUpdates automatically

Project type

Existing shells are not always cheaper if utilities or structure are poor.

Finished area

sq ft

Include bathroom and kitchenette area.

Construction market

Broad labor and material adjustment.

Utility/site complexity

Water, sewer, power, foundation, and access.

Contingency

Early concepts need a larger reserve.

Estimated result

$197,577–$293,957

Early-concept midpoint: $240,948.

How to interpret the result

Confirm zoning, occupancy, parking, utilities, fire separation, and rental rules before design spending.
Plan a no-step route, adaptable bathroom, usable doors, and controls from the beginning.

The tool applies this planning structure:

area × construction allowance + site/utilities + permits/design + accessibility premium + contingency

Land, financing, temporary housing, unusual foundations, utility impact fees, and local mandates are not fully modeled.
Some jurisdictions prohibit or limit ADUs.