A Guide to Accessory Dwelling Units

Setbacks

An ADU must fit within the setbacks of your zoning district

D

C

SITE REQUIREMENTS

B

A

LOT SIZE There is no minimum lot size requirement for building an ADU as long as your project meets the requirements of the San Marcos Development Code. Parking Your lot must be sized and configured so that one additional off- street parking space can exist in the third layer of the lot. Parking areas must be constructed from an all-weather surface. M aximum impervious cover The allowable impervious cover on a Single-Family - 6 lot may not exceed 50%. E asements or deed restrictions Be sure to check your property records to locate any utility, drainage, access or floodplain easements that may exist. No structures may be placed within an easement. It is the property owner’s responsibility to ensure compliance with all deed restrictions. S etbacks Your ADU must meet the required setbacks for an accessory structure identified by your zoning district. Single-Family - 6(SF-6) lots require:

Impervious Cover

Impervious cover percentage is the percent of lot area made up of impermeable surfaces such as pavement or rooftops which prevent the infiltration of water into the soil.

Impermeable

Permeable

Property Line

Parking Location

One additional parking space is required on-site and must be placed in the third layer.

SECONDARY FRONTAGE

3rd Layer

A B C D

Primary Street Setback: 25’ min. Secondary Street Setback: 15’ min.

2nd Layer

Property Line

1st Layer

PRIMARY FRONTAGE

PRINCIPAL FRONTAGE LAYERS

2nd & 3rd

Layer

No ADU Parking

Side Setback: 5’ min. Rear Setback: 5’ min.

1 Additional Parking Space

1st Layer

SECONDARY FRONTAGE LAYERS

Pg. 5

City of San Marcos Planning and Development Services Department