Answers / Buying
Can I build a guest house or ADU on my lot?
Direct answer
It depends on the zone. Miami 21, the City of Miami's code, allows an ancillary dwelling unit (ADU) in T3-L and T3-O, not T3-R. Most Shenandoah homes are T3-R: 175 of 228 mapped sales in the 24 months to September 28, 2026. A detached ADU is capped at 10% of the lot, up to 800 square feet.
Miami 21 Zoning Code, Article 4 Tables 3 and 4, Article 6 Table 13 and §3.18, as amended by Ordinance 14375 (October 1, 2025); City of Miami zoning map layer; Miami MLS closed sales inside Shenandoah's civic boundary. Checked October 29, 2026. The City or a real estate attorney confirms the rules for one lot. Method
What are the numbers behind it?
| ADU rule, City of Miami | Requirement |
|---|---|
| Zones | T3-L and T3-O; not T3-R |
| Lot | Must hold a single-family house |
| Maximum size, detached | 10% of lot area, up to 800 ft² |
| Maximum size, attached or inside the house | 10% of lot area, up to 500 ft² |
| Minimum size | Efficiency 275 ft², 1-bedroom 450 ft², 2-bedroom 550 ft² |
| Height | No taller than the main house |
| Parking | 1 space; none in a transit-oriented area or transit corridor |
| Entrance | Separate, not facing the street |
| Ownership | Same owner as the house |
| Renting it | Only with current proof of homestead; predominantly permanent housing; registered and renewed yearly |
Source: SEFMLS / MIAMI REALTORS®, September 27, 2022 through September 28, 2026. Data is deemed reliable but is not guaranteed accurate by the MLS and may not reflect all real estate activity in the market. Totals and medians only, no client names or addresses. Properties counted were listed or sold by various MLS participants, not necessarily by Gatien Salaun or Coldwell Banker Realty.
In more detail
What does that mean on a typical Shenandoah lot?
The median Shenandoah lot sold in the 24 months to September 28, 2026 was about 5,900 ft². At 10% of lot area, that caps a detached ADU near 590 ft² on a T3-O lot.
Where is a lot's zone shown?
On the City of Miami's zoning map. See what T3-R, T3-L and T3-O allow.
How was this counted?
Counted from the same MLS data as every figure on this site, for the stated window and boundary. Medians are withheld below 5 closings.
Canonical facts: Boundary