Alley Access Detection — What It Means for Investors

Alley Access Detection — What It Means for Investors

PropIntel detects whether a parcel has alley access — a secondary access point in addition to the primary street frontage. This field appears in the Detail Panel under the Details tab.

Why Alley Access Matters

ADU Opportunities Many municipalities require that Accessory Dwelling Units (ADUs) have a separate entrance from the primary residence. Alley access provides this naturally — the ADU can face the alley while the main house faces the street. Properties with alley access and ADU-permissive zoning are prime ADU candidates.

Duplex Conversions Converting a single-family home to a duplex often requires two separate entrances. Alley access enables this without requiring an awkward side entrance on the primary frontage.

Parking and Garages Properties with alley-accessed garages or parking areas have additional value. The alley provides vehicle access without consuming street-facing lot space.

Privacy and Rental Appeal For rental properties, alley access to a rear unit provides privacy for both the tenant and the property owner. This increases rental appeal and can justify higher rents.

How It Is Detected

PropIntel uses spatial analysis of parcel geometry against county road and alley centerline data. The analysis identifies parcels whose boundaries adjoin mapped alley rights-of-way.

Where It Is Shown

• Detail Panel > Details tab — Alley Access: Yes or No
• DataGrid — Alley Access column (may need to be enabled in column settings)
• Filters — Alley Access filter in the sidebar (where available)

Coverage

Alley access detection is currently available for counties with mapped alley centerline data. Not all counties provide this data in their GIS downloads. Coverage is expanding as we add more counties with alley data.

Investment Strategy

Combine alley access with these filters for targeted searches:

• Alley Access + Zoning R-3 or higher — Properties where ADUs are likely permitted
• Alley Access + Single Family + Large lot — Room for an additional structure
• Alley Access + Absentee Owner — ADU-potential properties with potentially motivated sellers

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