TOWN OF AMHERSTADU BYLAW PROPOSAL

Presentation to Planning Board

February 17, 2021

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

WHAT ARE ACCESSORY DWELLING UNITS?

• Accessory Dwelling Units (ADUs) are small dwelling units or apartments that exist on

the same property lot as a single-family residence

• Independent living space with kitchen, bath, and sleeping area

• Can be located within, attached to, or detached from the primary structure

• ADUs are common and referred to by many names:

• carriage house, back house, backyard bungalow, granny flat, in-law suite, alley house, guest house,

etc.

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021Source: AARP

A TOOL TO HELP HOUSING CRISIS

• Housing affordability

• ADUs generate rental income to help homeowners cover mortgage payments

• Expense to build ADU is for structure only as land is already owned

• Provides small-scale housing in majority single-family neighborhoods

• Important for development of “middle housing” (between apartments and large homes)

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021Source: AARP

A TOOL TO HELP HOUSING CRISIS

• Multi-generational housing and flexibility

• ADUs offer young people/young families entry-level housing choices

• ADUs enable families to expand beyond their primary home

• ADUs provide “empty nesters” the option of moving/downsizing into a smaller space

and renting out their larger home

• ADUs offer grandparents a place to live close to their children & grandchildren”

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021Source: AARP

A TOOL TO HELP HOUSING CRISIS

• Infill Housing and Environmental Benefits

• ADUs offer a way to include smaller, relatively affordable homes in established

neighborhoods with minimal visual impact and without adding to sprawl

• ADUs require fewer resources to build and maintain

• ADUs use much less energy for heating and cooling (especially contained units)

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021Source: AARP

ADU HISTORY

• Before 20th century, pre-zoning, people built as many homes as they wished on

their property

• Larger homes often had associated outbuildings, such as barns, carriage houses,

and worker housing

• Many carriage houses converted into rental homes – generating income for

landlords from otherwise unused outbuildings

• Automobile garages were built with housing units on top or have been

converted into housing

• ADUs highly regulated during post-WWII suburban development (one home

per lot)

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

ADU NATIONAL TRENDS

• In 2000, AARP and American Planning Association (APA) release model state

act and local code for ADUs

• Many state and municipal governments are legalizing and encouraging the

creation of ADUs

• In 2017, California required all cities and counties to allow ADUs with a

building permit

• In 2017, New Hampshire passed law that local zoning needs to allow ADUs

everywhere single-family homes were permitted

• Oregon requires cities of certain sizes to allow ADUs in single-family

neighborhoods

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

STATE AND REGIONAL TRENDS

• July 2018 survey of 100 Boston area towns by Pioneer Institute

• 37 allow ADUs, 31 allow temporary ADUs, and 32 have no ADU zoning

• Of towns that allow ADUs many restrict development with dimensional regulations,

permitting requirements, occupancy by relatives only, design guidelines

• Average of 2.5 permits annually per municipality

• MA Housing Choice Act (2021)

• Defined ADUs as 900 sq. ft. maximum or ½ floor area of the primary dwelling,

whichever is less (local govt can impose other restrictions)

• Only simple majority needed for adoption of ADU bylaw

• Still understanding impact of new legislation on Amherst

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

MA TOWN COMPARISON

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Town ADU Types ADU Permitting Square Footage Requirements Design Requirements

Amherst

Supp Apartment I

Supp Apartment II (10%)

Detached

SP for Detached and

Supp II350 min; 800 sq ft max (900 for ADA) DRB design guidelines

NorthamptonWithin Primary

Within Accessory StructureSP for Accessory 900 sq. ft. max New entryways are on the side or rear of house

Easthampton

Fully Contained

Expansion (33%)

Detached Structure

SP for all800 sq. ft. or 33% of exisiting residential space,

whichever is less

Match appearance of single-family house

Entrys on side or rear

Parking on side or rear

Greenfield

Within

Attached

Detached

SPR for Within and

Attached

SP for Detached

900 sq. ft. OR 33% of total gross floor area of

the largest existing unit in the home, whichever

is greater.

Compatible with Primary structure

Montague

Within

Attached

Detached Structure

SP for Within and

Detached900 sq. ft. max

resembles one-family home

entries are screened

Lexington

Basic

Expanded (40%)

Accessory Structure

SP for Expanded and

Accessory1,000 sq ft max

Maintain appearance and character of the principal dwelling

and those adjoining

Stairways enclosed within building

Somerville Backyard Cottage SPR 768 sq. ft. max

3' wide pathway for ambulance cot

Utilities underground

1.5 stories max (12 ft stories)

ADUs IN AMHERST

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

AMHERST ADUBYLAW HISTORY

• In 1968, Town Meeting amended zoning to allow

supplemental apartments within single-family

homes in only the R-O District

• Subsequent amendments expanded this to all

residential zoning districts (except R-F)

• 2014 update

• Added new categories: Supplemental Apartment I,

Supplemental Apartment II, and Supplemental Detached

• Existing requirements remained:

• Owner occupancy

• No additional lot area required

• No more than 3 adults

• Not used for lodging

• 350 sq. ft. min; 800 sq. ft. max (900 for ADA)

• Planning Board endorsed 7-0 and Town Meeting passed

amendment 102-48

2014 Update

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

2014 ADU Bylaw Update

• Allow Supplemental Detached Dwelling Unit to

have a new allowable maximum of 1,000 sq. ft.

(1,100 for ADA)

• Supplemental Apartments I and II remain at 800 sq.

ft. (900 for ADA)

• Unanimous support from Planning Board

• Creates a wider variety of living arrangements such as

two or three bedroom units which would benefit young

families looking for rental units in neighborhood settings

• Allows owners to downsize into ADU

• Amendment received a majority of Town Meeting

support but not the 2/3 required to pass

AMHERST ADUBYLAW HISTORY

2018 Proposal

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

2018 ADU Bylaw Update

AMHERST ADUBYLAW HISTORY • Recommendation 5.2.4 Supplemental Dwelling

Units (p. 100)

• Possible by-right provisions for SDUs

• Design guidelines

• Reduction in parking requirements

Relevant Plans

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Amherst Housing Production Plan (2013)

• Regulatory Recommendations; Smaller Scale

Housing (p. 6-7)

• Allow supplemental apartments by right in all

residential zoning districts

Amherst Housing Marking Study (2015)

• Section H.1.E (p.4.4; Demographics and

Housing)

• Make it easier to create attached and detached

accessory apartments in all residential zoning

districts

Amherst Master Plan (2010)

AMHERST ADUBYLAW HISTORY

Permitting Numbers

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Year 2015 2016 2017 2018 2019

Accessory

Units

Permitted

3 5 4 5 0

UNDERSTANDING AMHERST BYLAW

Additional

Lot Area

Required for

Unit

Square

Footage

Maximum

Owner

Occupancy of 1

unit

Occupancy Limit

ADU No 1,000 sq. ft. Required3 adults in ADU*proposed change to unrelated

Duplex Yes None Not Required 4 unrelated per DU

Converted

DwellingYes None

Required (or

resident manager)4 unrelated per DU

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

ADUs Around Town

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Paige Street • 2008

• Converted Garage

• 724 sq. ft.

ADUs Around Town

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Beston Street • 2015

• New Detached

• 422 sq. ft.

• Studio

ADUs Around Town

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Logtown Road • 2018

• New Detached

• 900 sq. ft. (ADA)

• 3 bedroom

ADUs Around Town

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Fearing Street • 2018

• New Attached

• 425 sq. ft.

• Studio

ADUs Around Town

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Wildwood Lane • 2015

• Fully Contained

• 560 sq. ft.

• 1 bedroom

ADUs Around Town

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Mill Lane • 2017

• Fully Contained

• 540 sq. ft.

• 1 bedroom

2021 BYLAW PROPOSAL

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

2021 ADU BYLAW PROPOSAL

• Accessory Dwelling Units (ADUs) are an important tool to

meet the dynamic housing needs of Amherst residents.

• This bylaw update proposes to increase the maximum square

footage of ADUs, create a more streamlined permitting

pathway, and adds additional design guidelines.

• Increasing ADU maximum square footage to 1,000 sq. ft. provides

opportunity for ADUs with more than 1 bedroom.

• Streamlining permitting pathway reduces barriers to ADU

development

• Design guidelines ensure ADUs are compatible with the scale and

character of the primary structure and surrounding neighborhood.

• Simplifies bylaw structure

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Purpose

2021 ADU BYLAW PROPOSAL

• Changing from “supplemental” to “accessory” to become consistent with federal, state, and industry terminology.

• Identify three discrete types of ADUs (contained, attached, and detached)

• Increase maximum square footage for all 3 types to 1,000 sq. ft. and eliminate minimum square footage.

• Attached ADUs (Supplemental II) no longer limited to 10% increase of primary structure square footage, simply defined as being attached to primary structure

• Attached and Contained ADUs allowed by-right (with requirements)

• Detached ADUs allowed by-right (with requirements) if less than 50% of primary structure habitable space (if larger, allowed by ZBA special permit)

• Added design guidelines requiring that the architecture and scale of any ADU is compatible with and secondary to the primary structure.

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Specific Changes

PROPOSED CHANGES SUMMARY

Name Square Footage Regulations Permitting

Supplemental Apartment I

Contained ADU

350 min; 800 max

1,000 max

By Right with Requirements

By Right with Requirements

Supplemental Apartment II

Attached ADU

350 min; 800 max; 10% increase

from primary dwelling

1,000 max

Special Permit

By Right with Requirements

Supplemental Detached

Detached ADU

350 min; 800 max

1,000 max

Special Permit

By Right (if less than 50% of primary dwelling);

Special Permit (if more than 50% primary)

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

Existing Bylaw

2021 Proposal

HABITABLE SPACE

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

ADU EXAMPLES

Lincoln Avenue

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

ADU EXAMPLES

Orchard Valley

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

ADU EXAMPLES

Echo Hill North

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

ADU RESOURCES

ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021

• AARP: All about Accessory Dwelling Units

• American Planning Association: Accessory Dwelling Unit Knowledgebase Collection

• Pioneer Institute (MA): The State of Zoning for Accessory Dwelling Units

• Mass.gov: Smart Growth Toolkit – Accessory Dwelling Units

Source: housable.com

Thank You We Welcome Your Questions and Feedback

For more information, contact

Ben Breger, Planner

bregerb@amherstma.gov

413-259-3187ADU Bylaw Proposal

Amherst Planning Department

February 17, 2021