City guide

Building a backyard home in Plano

Plano calls them Backyard Cottages — and thousands of lots qualify.

What Plano allows

Lot size
Minimum 6,000 sq ft lot.
Cottage size
400–1,100 sq ft, or 50% of the main home's habitable floor area — whichever is MORE restrictive — and not to exceed your zoning district's lot-coverage cap.
Sale restriction
The cottage cannot be sold separately from the main home — but there's no owner-occupancy requirement. The city's own fact sheet lists renting out the cottage, or living in it and renting the main house, as a benefit.
Parking
One additional off-street parking space is required.
Placement
Behind the main dwelling; height may not exceed the main home; architectural compatibility required; max one per lot.

The catch most people miss

Lot coverage can be the real limit, not the 1,100 sq ft formula: your house, garage, and every backyard building together are capped at a percentage of the lot that varies by zoning district (commonly 45%) — on a small lot with a one-story house, that can leave less room than the size formula alone suggests.

What it costs

The unit price you see advertised — the number on an online listing for the structure itself — is only part of the real cost: site work, utilities, permits, and delivery/crane are the rest. Check your property for a rule-based upper bound, then request help and we'll connect you with independent local professionals who can price the real number for your address.

Rules verified 2026-08-04 from City of Plano Backyard Cottage Fact Sheet. General guidance, not a determination for a specific property — zoning overlays, planned developments, and HOA/deed restrictions are address-specific.