City guide

Building a backyard home in Plano

Plano calls them Backyard Cottages — a second home on the same lot as your house.

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. The building-permit applicant must record a covenant with the county saying so (§15.1800.1.B and .4.A).

Renting it

No owner-occupancy requirement in §15.1800. The city's Backyard Cottage fact sheet lists long-term renting of the cottage, or living in it and renting the main house, as a benefit. Short-term rentals (stays under 30 consecutive days) are a separate rule (§15.2300): the cottage and main house count as one residence and cannot be two STRs, and new STRs are generally not allowed in single-family districts.

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 2026-09-13 from Plano Zoning Ordinance §15.1800 + Backyard Cottage Fact Sheet. General guidance, not a determination for a specific property — zoning overlays, planned developments, and HOA/deed restrictions are address-specific.