sf-ADU a guide for homeowners, designers, and contractors considering adding an Accessory Dwelling Unit to an existing residence in San Francisco SPONSORED BY THE SAN FRANCISCO PLANNING DEPARTMENT DECEMBER, 2018 PREPARED BY OPENSCOPE STUDIO, ARCHITECTS SF-ADU ACCESSORY DWELLING UNITS IN SAN FRANCISCO 01 TABLE OF CONTENTS SECTION 1 - Introduction 3 Land-Use Policy and ADUs Process Diagram SECTION 2 - Context and Codes 11 Housing Types in San Francisco Planning Code Considerations Building Code Considerations Miscellaneous Issues Planning and Permitting Process SECTION 3 - ADU Prototypes 35 PARTIAL GARAGE CONVERSIONS A - Single-family Residence B - Duplex C - Multi-family Residential Building FULL GARAGE CONVERSION D - Single-family Residence E - Freestanding Garage NON-GARAGE LOCATIONS F - Freestanding Rear Yard G - Single-family Residence 02 ACCESSORY DWELLING UNITS IN SAN FRANCISCO SF-ADU SECTION 4 - Financial Analysis 87 Construction Cost Income and Assets Financing SECTION 5 - Resources 95 Glossary California College of the Arts - Interior Urbanism Resource List Bibliography Credits SECTION 1 INTRODUCTION 03 INTRODUCTION Accessory Dwelling Units in San Francisco An Accessory Dwelling Unit (ADU) is a res- concerns about the seismic sustainability idential unit added to an existing building. of soft-story structures can be mitigated ADUs are subordinate to the primary residen- through the addition of a dwelling unit. tial unit(s), generally due to their location on This handbook serves as a guide for home- the lot and/ or the size of the unit. Also known owners or contractors when adding a unit to as Secondary Units, In-Law Units, or Granny an existing residential building. It helps define Flats, ADUs are generally developed using the various physical forms for ADUs; multiple underutilized spaces within a lot, whether a City Codes which regulate adding ADUs; and garage, storage, rear yard, or an attic. ADUs when such investment is financially feasible are independent units that have their own or beneficial to small property owners. kitchens, bathrooms and living areas. These units can be developed either within the The “Context and Codes” section reviews existing building, with an extension to the the main constraints on creating new ADUs, existing building, or as a separate structure. including the various Building Code and ADUs are more likely to utilize side entrances, Planning regulations. The “ADU Prototypes” exhibit lower ceiling heights, experience section outlines typical scenarios for creating lower light exposure, and so forth. an ADU based on a set of common residen- tial buildings found in San Francisco. The The City of San Francisco is facing growing “Financial Analysis” section summarizes the housing demands and an increasing need costs and benefits of building an ADU to help to encourage and facilitate more housing homeowners understand whether adding an options for residents. One promising strategy ADU to their property makes financial sense. is building new homes in existing residential The “Resources” section contains additional buildings. These added units are commonly background information to help understand known as Accessory Dwelling Units (ADUs) the issues at play, including definitions and and are also sometimes known as secondary code references. units, in-law apartments or granny flats. This handbook is a helpful first step to under- Much of the city’s existing housing stock has standing how an existing property might the capacity to legally include an additional be adapted to accommodate a new unit. housing unit, sometimes within the existing However, please note that it is not a replace- building envelope. The added unit can help ment for hiring a professional to help plan subsidize homeowner’s mortgage by creating your project. rental apartment, or can enable multi-gen- erational households; an older homeowner could move to the ADU while his or her children live in the main home. Additionally, 04 INTRODUCTION SECTION 1 PROCESS DIAGRAM Can I add a unit What could my unit Read the ADU handbook and nd How much could Looks like adding a unit to my building is This process usually includes an architect, City agencies and a contractor. The color-coded circles in the a prototype that most closely diagram below indicates key party responsible for each stage. in my building? look like? matches your property: the new unit cost? feasible. Where do I begin? I HAVE A I HAVE A MULTI-UNIT SINGLE-FAMILY HOME APARTMENT 1 Interview & select a Architect/Designer City Agencies Contractor design professional See Section 4 - Financial Analysis for issues relevant to your property. Design & Permitting see page 77 I want to keep my garage and potentially expand my See if your property is building. 2 Pre-Application 3 Preliminary 4 Complete 5 Submit zoned for an additional PROTOTYPE C see page 51 Meeting with DBI Project Design Construction Building Permit unit using the map on PROTOTYPE A see page 35 Drawings and Pay Fees page 15. not sure? Download the calculator I HAVE A FREE- STANDING spreadsheet and plug in GARAGE your numbers to ON MY PROPERTY estimate costs and potential revenue from 9 Bids From 8 Building 7 Revise 6 City Agency your new unit. Contractors Permit Issued Drawings per City Review Look up your property Agency Review on the online Property I want to replace my garage with a new unit. Information Map. download at: Here you will learn your WWW.SF-PLANNING.ORG/ADU PROTOTYPE D see page 57 10 Select Note: Contract bidding and selection property's zoning Contractor can start after Step 4. ! Potential control. If the density neighborhood permits, you can add one meetings & or more units. I HAVE A DUPLEX notication PROTOTYPE E see page 63 HTTP://PROPERTYMAP. SFPLANNING.ORG Construction still not sure? 11 Begin 12 Construction 13 Construction MY NEIGHBORS HAVE Construction Administration Inspections COTTAGES IN THE REAR YARD OR MY LOT FRONTS TWO I want to replace my STREETS Contact or visit the garage with a new unit. IMPORTANT ! ADU Planning Counter. see page 43 Read about the regulations in PROTOTYPE B Passed Inspections. ADU PLANNING COUNTER Section 2 related to your 1660 MISSION STREET prototype associated with your 1ST FLOOR SAN FRANCISCO, CA 94103 I want to keep my garage and property. Phone: (415) 865 - 5738 potentially expand my 14 Certicate of 15 Signo to 16 Handover to Owner Email: [email protected] building. Each prototype in Section 3 Occupancy Approve Final calls out the relevant Code Done! Your new PROTOTYPE D see page 57 PROTOTYPE F see page 71 requirements. Payment to Contractor unit is ready. SECTION 1 INTRODUCTION 05 Can I add a unit What could my unit Read the ADU handbook and nd How much could Looks like adding a unit to my building is This process usually includes an architect, City agencies and a contractor. The color-coded circles in the a prototype that most closely diagram below indicates key party responsible for each stage. in my building? look like? matches your property: the new unit cost? feasible. Where do I begin? I HAVE A I HAVE A MULTI-UNIT SINGLE-FAMILY HOME APARTMENT 1 Interview & select a Architect/Designer City Agencies Contractor design professional See Section 4 - Financial Analysis for issues relevant to your property. Design & Permitting see page 77 I want to keep my garage and potentially expand my See if your property is building. 2 Pre-Application 3 Preliminary 4 Complete 5 Submit zoned for an additional PROTOTYPE C see page 51 Meeting with DBI Project Design Construction Building Permit unit using the map on PROTOTYPE A see page 35 Drawings and Pay Fees page 15. not sure? Download the calculator I HAVE A FREE- STANDING spreadsheet and plug in GARAGE your numbers to ON MY PROPERTY estimate costs and potential revenue from 9 Bids From 8 Building 7 Revise 6 City Agency your new unit. Contractors Permit Issued Drawings per City Review Look up your property Agency Review on the online Property I want to replace my garage with a new unit. Information Map. download at: Here you will learn your WWW.SF-PLANNING.ORG/ADU PROTOTYPE D see page 57 10 Select Note: Contract bidding and selection property's zoning Contractor can start after Step 4. ! Potential control. If the density neighborhood permits, you can add one meetings & or more units. I HAVE A DUPLEX notication PROTOTYPE E see page 63 HTTP://PROPERTYMAP. SFPLANNING.ORG Construction still not sure? 11 Begin 12 Construction 13 Construction MY NEIGHBORS HAVE Construction Administration Inspections COTTAGES IN THE REAR YARD OR MY LOT FRONTS TWO I want to replace my STREETS Contact or visit the garage with a new unit. IMPORTANT ! ADU Planning Counter. see page 43 Read about the regulations in PROTOTYPE B Passed Inspections. ADU PLANNING COUNTER Section 2 related to your 1660 MISSION STREET prototype associated with your COUNTER 38 FIFTH FLOOR I want to keep my garage and property. SAN FRANCISCO, CA 94103 potentially expand my Phone: (415) 865 - 5738 building. Each prototype in Section 3 14 Certicate of 15 Signo to 16 Handover to Owner Occupancy Approve Final Email: [email protected] calls out the relevant Code Done! Your new PROTOTYPE D see page 57 PROTOTYPE F see page 71 requirements. Payment to Contractor unit is ready. 06 INTRODUCTION SECTION 1 ADUS AS A HOUSING POLICY Accessory Dwelling Units in San Francisco Adding apartments to existing, older housing stock is a small-scale residential infill strategy which complements the current housing development trends in San Francisco. Most of the current development occurs on lots that are signifi- cantly underdeveloped or vacant, through demolishing the existing use and constructing a new residential (or mixed use) building. The majority of the city’s residentially-zoned land is already built with a single family houses or a multi-unit apartment buildings.