City guide

Building a backyard home in McKinney

McKinney publishes its own ADU guide — a city that wants you to succeed.

What McKinney allows

Eligibility

Single-family residential zoning with room to meet regulations. Planned Development (PD) zones may not allow an ADU — address-specific check required.

ADU size

Main home under 1,200 sq ft → ADU up to 75% of its area. Main home 1,200 sq ft or more → up to 50%.

Height & setbacks

ADU cannot exceed the main house height; setbacks match the main home's zoning district.

Parking

4+ existing spaces → none added; fewer → add 1; Historic Overlay District → 3 total.

Utilities

The ADU shares the main home's meters — no separate electric account.

The catch most people miss

PD zoning. A large share of newer McKinney neighborhoods sit in Planned Developments with their own rules — the city's general ADU rules may not apply to your address. This is exactly what our report checks first.

What it costs

The factory price is only part of the real number — site work, utilities, permits, and delivery/crane are the rest. Your Owner's ADU Roadmap gives a specific budget band for your address, plus the exact permit path and everything you need to run the project yourself (or have us run it).

Rules verified 2026-07-12 from Building an ADU in McKinney (official city guide). General guidance, not a determination for a specific property — zoning overlays, planned developments, and HOA/deed restrictions are address-specific.