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How Much Do You Know About ADUs? – 101 Compelling Facts About Accessory Dwelling Units


Did you know that in California the number of ADUs (Accessory Dwelling Units) has grown exponentially in number as more cities, counties, and homeowners become interested in ADUs as one solution to increasing the supply of affordable housing? One benefit of building an ADU is they give homeowners the flexibility to share independent living areas with family members and others, allowing seniors to age in place as they require more care. That’s amazing!  We know finding facts and figures about ADUs can be time-consuming and frustrating, so we put together this list of the top 101 facts, notes, and statistics so you can easily reference them and refer back to them any time in the future.  This space is constantly changing, so if you see a fact that is not up-to-date, feel free to let us know. And if you know a stat that we should add, let us know that too!

Table of Contents

Fact #1: An Accessory Dwelling Unit Is A Secondary Residential Unit On A Single Property. 

They are often known by other names like “granny flats”, “mother-in-law suites”, or “backyard cottages”.


Fact #2: Legally, ADUs Are Part Of The Same Property As The Main Dwelling. And, That’s What Sets Them Apart. At The Same Time, An ADU Cannot Be Bought Or Sold Separately From The Main Property. 

It follows that the owner of the main home also owns the ADU.


Fact #3: ADUs Can Be Fully-Functional.

They can be stand-alone homes with full kitchens, bathrooms, and living areas, while others attach to your current home and simply include kitchenettes, bathrooms, and sleeping spaces. 


Fact #4: ADUs Are A Great Way To Optimize Space On Your Property While Providing Additional Functionality — And Long-Term Resale Value. 

It can add value to a property and increase the resale value of a property.


Fact #5: The Maximum Allowed ADU Size Is 1,100 SF.

This will comfortably accommodate two bedrooms. The maximum allowed for a second-floor area is 600 SF.


Fact #6: ADUs Pose As A Possible Solution To The Affordable Housing Crisis In The West Coast.

ADUs give homeowners the chance to maximize the use of their land by building an additional home on their property.


Fact #7: Seattle And The Entire State Of California Have Recently Passed New Rules That Make It Easier For Homeowners To Construct An ADU On Their Property And Offer It To Renters.

ADUs offer renters the flexibility to find affordable housing in these expensive areas. Cities see them as a way to quickly alleviate the need for affordable housing.


Fact #8: Homeowners Build ADUs In Preparation For The Future.

Families can use this space to house adult children, giving them a separate and private living area or house a senior family member who wants the independence of living alone but the security of having relatives nearby. Similarly, a growing number of aging homeowners are considering building an ADU to accommodate a future live-in caretaker.


Fact #9: The Most Common Reason For Homeowners To Build An ADU Is To Provide Affordable Housing For Their Families. 

They want to provide affordable housing for elderly parents, affordable housing for boomerang kids, and even affordable housing for themselves—with the ability to share their main home with even more families. Throw in a dash of retirement security from potential rental income, and they’ve got themselves a pretty impressive plan to combat housing affordability for their family.


Fact #10: ADUs Can Be An Effective Solution For Family Caregivers And People With Disabilities.

The elderly demographic is living longer, and as the likelihood of developing a disease rises with age, they will need in-home treatment. Since the majority of older people choose to age in their own homes, they may need more in-home care as they get older.


Fact #11: ADUs Can Be An Economic Solution For Many Strained Under The Weight Of High Housing Costs Such As Aging Homeowners, Single Parents, And College Graduates Saddled With Student Loan Debt.

The societal benefits associated with the creation of accessory dwelling residences cannot be overstated.


Fact #12: ADUs Make Cities More Livable.

Since it enables senior citizens to live in healthy family settings and in neighborhoods with facilities and facilities that enable them to live actively, peacefully, and with dignity.


Fact #13: The Newest Wrinkle In The ADU Business Is Popularly Called A Granny Pod. 

It offers high-tech monitoring capabilities so that the inhabitant can be checked on via remote access. Other devices include a timed medication dispenser. The amenities that can be installed include a toilet that checks temperature and does simple urinalysis.


Fact #14: Aging In Place Is A Movement That Allows Older People To Maintain Some Autonomy While Keeping Them Out Of Care Facilities. 

ADUs are a solution for this rapidly growing subset of people.


Fact #15: ADUs Increase The Supply Of Affordable Housing Without The Need For More Infrastructure Or Further Land Development.

Their smaller size allows for better integration into communities with minimal negative impact to neighborhood character.


Fact #16: ADUs Can Be Used As An Area Dedicated To Work, Like A Home Office.

Remote jobs are becoming more and more popular, and those who work from home often want a space they can retreat to where they can focus without getting distracted.


Fact #17: Other People Leverage Their ADU As An Extra Source Of Income.

They rent the unit out to tenants, or list it on homestay sites like Airbnb and VRBO.


Fact #18: Two ADU Types Exist: Attached And Detached.

Depending, on which you’re building, the regulations will vary slightly, so it’s important to research regulations for the type of ADU you’re trying to build.


Fact #19: An Attached ADU Attaches Within Your Primary Structure. 

They can be additions to your house, garage conversions, and basement of attic conversions.


Fact #20: A Detached ADU Is A Stand-Alone Unit, Usually Situated In The Backyard Of The Property. 

It can be a tiny house or cottage that is not attached to the main structure at all. Detached ADUs tend to be a more expensive and involved project than attached ADUs.

Fact #21: A Garage ADU Makes Use Of An Attached Or Detached Garage By Converting The Space Into A Residence.

Other options involve adding a second-story ADU above a garage or building a new structure for both people and cars.


Fact #22: An Internal ADU Is Created When A Portion Of An Existing Home Is Partitioned Off And Renovated To Become A Separate Residence.

This can be an entire floor, part of a floor, or an attic or basement. 


Fact #23: A Lower-Level ADU Is Typically Created Through The Conversion Of A Home’s Existing Basement, During Construction Of The House, Or As Part Of A Foundation Replacement And House Lift.

For this type of ADU, height and safety conditions must be met.


Fact #24: The Planned Use Of An ADU Usually Determines Its Design.

The ADU should be equally responsive to changing needs. That is, it is designed to be adaptable to the needs of different families or people at different life stages. Universal architectural features will be applied to the room for those who have or may have reduced mobility as they age.


Fact #25: ADUs Are Typically Owned And Managed By Homeowners Who Live On The Premises. Such Landlords Are Less Likely To Raise The Rent Once A Valued Tenant Has Moved In.

The income provided by an ADU tenant can be especially important for older people on fixed incomes.

Fact #26: Market Rate Rents For ADUs Tend To Be Slightly More Than For Similarly Sized Apartments.

But they often represent the only affordable rental choices in single-family neighborhoods, which typically contain no studio or one-bedroom housing options at all.


Fact #27: Some Municipalities Are Boosting ADUs As Part Of Affordable Housing And Anti-Displacement Strategies.

Santa Cruz, California, is one of the cities with services to assist low-income families in constructing ADUs or residing in them at consistently low rentals.


Fact #28: ADUs Work Well For The One- And Two-Bedroom Homes Needed By Today’s Smaller, Childless Households.

ADUs generally measure between 600 and 1,000 square feet and are perfect for childless households which now account for nearly two-thirds of all households in the United States.


Fact #29: ADUs Use Significantly Less Energy For Heating And Cooling.

Of all the ADU types, internal ones tend to have the lowest building and operating costs.


Fact #30: ADUs Offer A Way To Include Smaller, Relatively Affordable Homes In Established Neighborhoods With Minimal Visual Impact And Without Adding To An Area’s Sprawl.

ADUs are community-compatible.


Fact #31: ADUs Provide A More Dispersed And Incremental Way Of Adding Homes To A Neighborhood Than Other Options, Such As Multistory Apartment Buildings.

As a result, it’s often easier to get community support for ADUs than for other housing types.


Fact #32: While Today’s Interest In ADUs May Be New, The Housing Type Is Centuries Old. 

Early settlers often built a small home to live in while constructing their larger, primary house nearby.


Fact #33: With The Rise Of Suburban Single-Family Home Developments Following World War II, ADUs Practically Ceased To Be Built Legally In The United States.

Now, regardless of acreage or exceptions, suburban zoning codes usually allowed only one home per lot. Garages, both attached and detached, used up yard space that should have been used for ADUs.


Fact #34: Elsewhere, Even In Rural Areas With Ample Land, Property Owners Are Often Prohibited From Creating Secondary Dwellings.

Many communities no longer allow new ADUs, even though they did in the past — and even though they do now. (Many units in single-family homes or yards are legally unlawful, but they are permitted since they were built before such dwellings were legal.)


Fact #35: ADUs Began Making A Comeback In The 1980s.

As cities explored ways to support smaller and more affordable housing options within single-dwelling neighborhoods.


Fact #36: In 2000, In Response To A Growing Demand For ADU-Supportive Guidelines, AARP And The American Planning Association Partnered To Release An Influential Model State Act And Local Code For ADUs.

More recently, there has been increased interest at the state and local levels in legalizing and promoting the construction of ADUs, fueled by rising housing costs and, in some cases, the expectation that homeowners with enough land should not be limited in their use of their lands.


Fact #37: Barriers To The Growth Of ADUs Include Municipal Statutes, Zoning Laws, Building Restrictions, Neighborhood Covenants, And Other Regulations.

Many homeowners either neglect or skirt around those rules, which is comparatively straightforward to do when converting a garage or other existing structure but more difficult when constructing a new structure.


Fact #38: Zoning Laws May Limit What Types Of Outbuildings You Can Build On Your Property, And You May Need A Permit Before You Can Build.

While regulations for building an ADU vary between cities, there are a few things you should consider first. Depending on your lot size, you may only be able to build certain sizes of ADUs.


Fact #39: The Zoning Authority Will Often Have Guidelines For How To Manage Utilities. Often, These Will Be Connected And Billed Separately From The Main Residence.

Some municipalities have mandates in place to ensure that connection and utility fees remain reasonable, so as not to discourage the development of ADUs. California, for example, has a statewide mandate requiring that connection and utility fees “shall not be disproportionately higher than those to develop primary dwellings.”


Fact #40: Even If The Homeowner Intends The ADU To Be Occupied By A Relative, It Is Advisable To Install Sub Meters For Utilities At The Time The Dwelling Is Built, As This Is Less Expensive Than Installing A Submeter After The Fact And Desirable For Resale Purposes.

Separate meters will allow ADU inhabitants to save energy and water by holding them financially accountable for the energy and water they use. Billing is often made easier with separate metering.


Fact #41: People Over 50 Who Would Consider Building An ADU Said They Would Do So In The 2018 AARP Home And Community Preferences Survey. 

  • Provide a safe haven for a loved one who is in need of assistance (84% )
  • Give family or mates a place to stay (83%)
  • Getting someone living nearby makes you feel better (64%)
  • Have a place for visitors to stay (69%)
  • Boost the worth of their house (67%)
  • Make a place to stay for a caregiver (60%)
  • Renting to a roommate will help you make extra money (53%)


Fact #42: Some ADUs Are Factory Made.

They’re built off-site and put together like a kit. This one-size-fits-all approach may work for some, but the reality is families (as well as their properties) are not one-size-fits-all. Everyone has specific needs that require customization, personalization, and creative thinking.


Fact #43: Every Town And City In California Has Specific Rules And Regulations Surrounding The Use And Construction Of ADUs In Their Area. 

Rules can even change by lot and neighborhood, and you need to make sure your design and construction partner understands how to navigate their rules. Provisions change all of the time. Every regulation is subject to the interpretation of individual city planners. It’s one thing to review the rules. It’s another to interpret the rules and be able to advise you on how to maintain compliance.


Fact #44: ADUs Are Not Cheap Gimmick Projects. ADUs Are Homes.

Just because the Accessory Dwelling Unit is small doesn’t mean it’s cheap. Building in California can be expensive, and different jurisdictions require different provisions. A great way to approach your project is to really think about why you’re getting started. Are you looking to develop a housing plan for your family? Will it be an asset for you and your family for years to come? If the answer is yes, approach building an ADU like any other construction project.


Fact #45: Since ADUs Make Use Of The Existing Infrastructure And Housing Stock, They’re Also Environmentally Friendly And Respectful Of A Neighborhood’s Pace And Style.

An increasing number of towns, cities, counties and even states have been adapting their zoning or housing laws to make it easier for homeowners to create ADUs.


Fact #46: As Of January 1, 2020, Homeowners Who Created Accessory Dwelling Units Without The Required Building Permits May Have The Opportunity To Bring Their ADUs Into Compliance. 

For ADUs that were constructed without building permits, local building officials now have the option to inspect an ADU and apply the building standards that were in effect at the time the unit was constructed.


Fact #47: It Seems That The Cheapest Someone Could Build An ADU For Would Be Around $125k-$175k For A Very Basic, Simple Unit.

It would depend on whether it will be built from the ground up or from an existing structure. It would also consider several other factors (i.e. where is the sewer line, power, gas line, parking etc.)


Fact #48: Local Authorities Cannot Enforce Minimum Requirements For Accessory Dwelling Unit Floor Plans, Lot Coverage, Or Open Spaces Under California’s Accessory Dwelling Unit Law, Assembly Bill 68, Assembly Bill 881, And Senate Bill 13.

Local governments may set a maximum size for ADUs, but it must be at least 850 square feet for a one-bedroom unit and 1,000 square feet for multiple units.


Fact #49: It Is No Longer Required To Have Off-Street Parking Spaces If You Convert The Garage Or Carport Into An ADU. 

Off-street parking had to be allocated for spaces missed due to the conversion prior to SB-1069. This condition was removed from the new bill if the converted device met any of the following criteria:

  • It is within a half-mile of a mass transportation system.
  • It’s in a historically and architecturally important neighborhood.
  • On-street parking permits are required, but they are not given to the new unit’s occupant.
  • Within one block of the new unit, a ride sharing vehicle can be identified.
  • Replacement parking spaces would have to be accommodated on the premises for units that do not follow any of the aforementioned requirements.


Fact #50: A Stipulation For HOA Communities Is Included In The Proposed Accessory Dwelling Unit California Rules. Assembly Bill 670 Nullifies All Provisions In A Homeowners Association’s Regulatory Documents Prohibiting The Building Or Usage Of Accessory Dwelling Units On Single-Family Dwellings.

As a result, creating HOA granny units or secondary housing units on one’s property has never been simpler.

Fact #51: The Main Purpose Of California’s New ADU Laws Is To Address The Housing Crisis In Many Parts Of The State. However, Constructing ADUs Can Be Very Beneficial For Homeowners. 

By renting their ADUs to low- and moderate-income families, homeowners can also create an additional stream of income. This can offset some of the costs of owning a home, which can be crucial during times of economic downturn or a pandemic.


Fact #52: With Access To Historical Multiple Listing Service Data, Researchers Looked For Evidence Of ADUs As Far Back As 1997 And Discovered That The Trickiest Part Was In The Jargon.

The biggest challenge of collecting ADU data from MLS unstructured text was understanding the multitude of terminology and physical forms applicable to ADUs in different locales. There are many terms for ADUs, like granny flat, guest house, in-law suite, and casita among others.


Fact #53: In The 10 Years Between 2009 And 2019, Year-Over-Year Growth Of First-Time Listings Of ADUs Averaged 8.6%.

ADU growth especially in the Northwest has indeed been serious.


Fact #54: Using The 1997-2019 Multiple Listing Service (MLS) Transactions Data, Freddie Mac’s Study Identified 1.4 Million Properties With Accessory Dwelling Units (ADUs) In The United States. 

The study showed that first-time listings with ADUs grew most rapidly during the last decade. While the number and share of ADU listings increased across the United States, the growth was higher in the South and West – the fastest growing regions of the country.


Fact #55: Since ADUs Are Legally Part Of The Same Property As The Main House, The Census And Most Other Government Housing Surveys Fail To Identify Them.

In places where construction of ADUs is now legalized, building permit data can serve as a good proxy for the number of new legally built ADUs but do not capture unauthorized units coming to the market illegally. 

As a clever alternative, the Freddie Mac team analyzed over 600 million MLS transactions going back to 1997 and identified listings mentioning ADUs for the first time, thus estimating monthly additions to the national ADU inventory.


Fact #56: The Freddie Mac Estimates Show That The Number Of First-Time Listings With ADUs, Including For-Sale And For-Rent Units, Increased Noticeably During The Last Decade.

Close to 70,000 properties with ADUs were sold in 2019, representing 4.2% of total homes sold on MLS. By comparison, only 8,000 properties (1.1%) with ADUs were sold in 2000.


Fact #57: The percentage and number of rental ADUs increased as well. Close to 8,000 ADU rentals were leased in 2019, representing 2.9% of total homes leased on MLS. By comparison, less than 1,000 ADU rentals, or 1.2%, were leased in 2000.

The growth in ADUs matches NAHB survey data, which find that ADU development was widespread in the remodeling industry.


Fact #58: The Study Identified Portland, Dallas, Seattle, Los Angeles, And Miami As The Fastest Growing ADU Markets, Each With Double-Digit Growth Of First-Time ADU Listings Since 2015. 

Detached ADUs are more prevalent in sprawling Western metro areas, while homeowners in denser East Coast cities are more likely to create attached ADUs through conversion of attics, basements or garages.


Fact #59: The U.S. Census Bureau determined that in 2017, California had a rental housing vacancy rate of just 4.3 percent, with only five other states reporting lower vacancy rates. 

California cities are looking for ways to bring new housing units online quickly and affordably, and in some cases, ADUs fit that bill.


Fact #60: Many Cities And Counties Permit ADUs In One Or More Single-Family Zoning Districts By Right, Subject To Use-Specific Standards.

Common provisions include an owner-occupancy requirement (for one of the two dwellings), dimensional and design standards to ensure neighborhood compatibility, and off-street parking requirements.


Fact #61: In Some States, Such As California And Vermont, Localities Must Permit ADUs By Right, Under Certain Conditions. 

State laws preempt some aspects of local zoning for ADUs or actively encourage cities and counties to adopt permissive zoning regulations for ADUs.


Fact #62: Many Older Communities Have An Existing Supply Of Illegally Created ADUs. Some Of These Communities Offer, Or Have Offered, Some Form Of Limited Amnesty To Owners Of Illegal ADUs. 

These amnesty programs may waive permitting and inspection fees in exchange for owners registering their units, and they typically expire within a year or two of adoption.


Fact #63: ADUs Are Only Permitted In Residential Zones.

Cities are composed of buildings with varying uses – residential, commercial, industrial, among others so location and zoning are important variables to consider when planning to build an ADU.


Fact #64: A Significant Driving Force In Accessory Dwelling Units Is The Ability To Subdivide The Lot And Sell An ADU Separately From The Main House.

The condo model splits the land, making it possible to sell the ADU separately. More people are considering this alternative as a way of obtaining capital as a result of this opportunity.


Fact #65: In A Survey Of ADU Owners In Santa Cruz County, CA, More Than Half Said They Used Personal Savings And About 40% Said They Used A Home Equity Line Of Credit For Design And Build. A Refinance Product Was Used By Less Than 10% Of The People.

Commercial lenders and credit unions offer a Home Equity Line of Credit (HELOC) and other home refinance options, such as cash-out refinances.


Fact #66: Building An ADU Is An Affordable Way To Own An Investment Property. 

If you are not yet ready to buy a separate home as an investment, you can start with constructing a granny flat first.


Fact #67: Building An ADU Requires Much Of The Same Research, Contemplation, And Preparation As Making Any Other Large  Financial Investment. 

Families should evaluate their interests and budgets to see if constructing an ADU is a successful investment.


Fact #68: Municipalities Nationwide Have Been Relaxing Their Restrictions Against ADUs, And Some States Have Been Encouraging Their Creation By Requiring Communities To Allow Them.

Depending on the community, virtually every house may be converted into an ADU as long as height restrictions, property line setbacks, and location restrictions in relation to the primary residence are adhered to.

Other groups begin with the basic specifications and then add extra requirements, making it difficult to construct an ADU.


Fact #69: In 2017, California Required All Of Its Cities And Counties To Allow ADUs So Long As The Property Owner Secured A Building Permit.

Mayor Eric Garcetti of Los Angeles has stated that ADUs will supply the city with 10,000 housing units. He promotes ADUs as a way for homeowners to contribute significantly to the expansion of our city’s housing supply while still earning some extra cash.


Fact #70: A New Hampshire Law Established That Local Zoning Codes Had To Allow ADUs Nearly Everywhere Single-Family Housing Was Permitted.

The change stemmed in large part from the frustration of builders who couldn’t construct the type of amenities, such as backyard cottages and garage apartments, that their clients desired.


Fact #71: ADUs Are Usually Created By Enthusiastic And Motivated Amateurs.

Although ADUs are occasionally designed into new residential developments, the vast majority are created by individual homeowners after they move in.


Fact #72: An ADU May Present The Ultimate Chance For A Do-It-Yourselfer To Build His Or Her Small Dream Home.

More often, homeowners bring in a combination of architects, designers and construction contractors to do the work, much as they would for a home addition or major kitchen remodeling. 

The local municipality’s planning department can provide guidance on the rules for ADUs and information about what permits, utility connections and fees are involved.


Fact #73: Regulations About ADUs Are Typically Written Or Adopted At The Local Government Level.

Where it’s legal to build ADUs, homeowners still need to follow rules about where it can be done, how tall they can be, how many square feet they can contain, what they can look like and how they can be used. These rules can be found in the local zoning code.


Fact #74: After Portland, Oregon, Relaxed Its ADU Rules In 2010 And Waived Impact Fees (A Savings Of Up To $12,000), The Number Of ADUs Built There Increased From About 30 Per Year Between 2000 And 2009 To Practically One ADU A Day In 2015.

Over the past few decades it has become clear that there’s a balance to strike between the strictness of ADU regulations and how often ADUs get built.


Fact #75: Changes In California’s ADU Laws Allowed Los Angeles To Achieve An Even More Dramatic Increase, Going From 80 Permit Applications In 2016 To Nearly 2,000 In 2017. 

This allowed both an ADU and a “Junior ADU,” or JADU, on land in Sonoma County — an interior ADU of 500 square feet or less — one of the immediate measures enacted in the aftermath of Northern California’s many destructive fires.

Fact #76: In Many Jurisdictions, Well-Intentioned But Burdensome Rules Can Stymie The Creation Of ADUs.

ADU-related zoning codes should be restrictive enough to prevent undesirable development but flexible enough that they actually get built.


Fact #77: Recognizing That ADUs May Represent A New Housing Type For Existing Neighborhoods, Communities Often Write Special Rules To Ensure They’ll Fit In Well. 

Visual alignment with the primary residence, appearance from the street (if the ADU can be seen), and anonymity for neighbors are usually addressed in these guidelines.


Fact #78: Each Community Can Strike Its Own Unique Balance Between Strict Rules To Ensure That ADUs Have A Minimal Impact On Neighborhoods And More Flexible Rules That Make Them Easier To Build.

This can be achieved by strictly adhering to zoning codes and rules in your city or community.


Fact #79: It’s Not Uncommon For Homeowners To Convert A Portion Of Their Residence Into An ADU In Violation (Knowingly Or Not) Of Zoning Laws Or Without Permits.

Such illegal ADUs are common in cities with tight housing markets and a history of ADU bans. One example is New York City, which gained 114,000 apartments between 1990 and 2000 that aren’t reflected in certificates of occupancy or by safety inspections.


Fact #80: A Survey Of ADU Owners In Three Pacific Northwest Cities With Mature ADU And Short-Term Rental Markets Found That 60 Percent Of ADUs Are Used For Long-Term Housing As Compared With 12 Percent For Short-Term Rentals.

Short-term rentals may be more lucrative than long-term rentals in common cities, enabling homeowners to recoup their ADU costs faster. In addition, short-term rentals will provide owners with enough revenue to enable them to rent out their ADU to friends and family on occasion.

However, if ADUs primarily serve as short-term rentals, such as for Airbnb and similar services, it undermines the objective of adding small homes to the local housing supply and creating housing that’s affordable.


Fact #81: One Of The Best Things About Having An Accessory Dwelling Unit As Part Of Your Property Is Its Flexibility.

ADUs may be used in a variety of forms, including the fact that they are usually constructed in the shape of a small house or apartment.


Fact #82: In View Of The COVID-19 Pandemic, Remote Working And Interactive Classrooms Have Become The “Latest Standard” For 1 In 4 American Employees And Nearly 93 Percent Of Households With School-Aged Children. Such Units Are Being Seen As A Solution To The Challenges That Such Scenarios Will Offer.

For some, ADUs are serving as detached office spaces or homeschool spaces, allowing remote workers and students to maintain a sense of balance between their work and home or school lives.


Fact #83: With COVID Driving More And More People To Stay Closer To Home For Work And School, The Appeal Of These Separate Living Spaces Is Predicted To Rise. 

Being aware of and complying with local zoning regulations is key to ensuring that the ADU will remain a viable solution for families that is both affordable and good for the environment.


Fact #84: Many ADUs Fall Into The Tiny House Category, And The Surge In Interest In Tiny House Living Has Been A Boon To Grandparents Who Are Interested In This Type Of Housing.

As multigenerational housing becomes more accepted, ADUs are likely to become more prevalent. Realtors and builders report that they are already a good selling point.


Fact #85: It Takes Between 10 To 12 Weeks To Build An ADU From Scratch. 

This is just the build. And it doesn’t allow time for building sites that are slightly more complicated or require significant changes before the building work can even begin.


Fact #86: The Time Spent On Building An ADU Can Be Minimized If You Plan Appropriately. It Would Be Wrong To Assume That All ADU Builds Will Be Straight Forward.

Some building situations are much more complicated than others and the various stages can vary significantly in duration.


Fact #87: When Building An ADU, It Is Usually A Good Idea To Consult A Professional Right From The Assessment Stage.

It is hard for a layman to understand certain property limitations or regulations that may make the project much more expensive and difficult.


Fact #88: ADUs Can Complement People’s Lifestyle While Also Providing Solutions To Life’s Challenges.

Despite the fact that many people purchase and live in their homes for decades, their desires change.


Fact #89: There Are A Lot Of Reasons Cities Stand To Benefit From ADUs. Affordable Housing, And Lack Thereof, Is At The Top Of The List.

Cities such as San Francisco, San Diego, Los Angeles, Portland, Seattle, and Austin face rising rent costs and a scarcity of housing.


Fact #90: According To 2018 Reports, San Diego, A City Of 1.4 Million, Is Expected To Grow By One Million People By 2050.

ADUs aren’t going to fix California’s housing shortage, but they will certainly improve.


Fact #91: An ADU Will Increase The Assessed Value Of Your Property And May Increase Your Property Taxes As Well. 

It really depends on your state and if there are property tax caps that you have already reached.


Fact #92: ADUs In San Diego  Have Become Increasingly Popular In Recent Years Due To Their Convenience, Privacy, And Versatility For Homeowners.

70% of San Diegans cannot afford to purchase a house in this area, with the average property price now at $610,000. 

Fortunately, new laws have been introduced that would make it simpler for homeowners to construct an ADU in San Diego, including expedited ADU approvals, the right to use pre-approved county construction plans, and the waiver of some fees.


Fact #93: There Are No Laws In San Diego (Or The Rest Of California) That Prohibit Homeowners From Renting Out Their ADU To A Tenant, As Long As The Living Space Meets Regular Requirements. 

It is important to note, however, that anyone renting a granny flat in San Diego must sign a rental agreement that includes a minimum of 30 days occupancy.


Fact #94: Inglewood, Nestled Nicely In The South Bay Of Los Angeles County, Boasts One Of The Most Lenient ADU Ordinances In The State.

Not only are there no lot size limitations in Inglewood, but there are also no construction limits, height restrictions, a limited number of apartments, or a minimum size for an ADU of only 150 square feet. If you really wanted to, you might fit the ADU into your little backyard.


Fact #95: Just A Short Drive From San Diego, You’ll Have La Mesa. This City Has No Parking Requirements For Your ADU.

There are also no restrictions for listing your ADU on AirBnB, making this a prime spot for short term rentals.


Fact #96: Lakewood’s ADU Regulations And Fees Are Almost Identical To Inglewood’s Meaning, You Can Build Your ADU With Ease And Little Restrictions.

Lakewood is a city in Los Angeles County that is bordered by Long Beach and Cypress. Despite its reputation as a more residential town than its neighbors, this area is ideal for those who work in the city but want a more tranquil setting to live in.


Fact #97: The City Of Pasadena Has Recently Passed The Affordability Covenant And Landlord Agreements For Accessory Dwelling Units. With These Documents, Property Owners Can Apply For A Reduced Residential Impact Fee, Which No Doubt Will Be A Great Relief On Your Wallet.

Los Angeles County takes the cake again with yet another city on the best list. Even without the fee reduction, property owners looking to build an ADU can expect to pay just about $29,000 in fees. Plus, there are no minimum or maximum unit restrictions and no parking restrictions for converted ADUs.


Fact #98: Shasta Lake, Located In The Northernmost Portion Of California, This City Is Known For Its Beautiful Tourist Destinations, Making This A Prime Place For Building An ADU For Short Term Rentals.

Not very many people know about Shasta Lake, but they should because it’s a great place to build an ADU. There are no lot size requirements and maximum ADU sizes are generous at 1,200 square feet. There are also no restrictions on the number of bedrooms your ADU can contain as long as you stay within the size regulation.


Fact #99: Walnut Creek Of Contra Costa County Is One Of The Worst Cities To Build An ADU.

Despite being just a short BART trip from San Francisco, Walnut Creek fails to impress with its stringent specifications. An ADU’s overall size is limited to 950 square feet. ADUs must also fit the current key home on the property precisely, according to the city. This entails the use of the same colors, textures, windows, and other elements. Walnut Creek has also provided a lengthy ADU handbook that describes all of the necessary design elements. Don’t forget about the costs. The typical homeowner can budget $69,000 to pay expenses such as traffic calming, a construction design approval charge, and other costs.


Fact #100: Atascadero, A City Of San Luis Obispo County Has The Potential To Be A Great ADU City But It Currently Prohibits 34 Areas From Building. This Makes It Almost Impossible For Most Homeowners To Get Approved In Addition To All Of The Other Requirements.

In 2018, the city of Atascadero accepted only five ADU programs. This is a shockingly low number, particularly for a town known for its wineries, which make it a popular tourist destination.


Fact #101: Los Banos Of Merced County In Central California Follows The Normal State Laws For ADUs But Requires An Accessory Dwelling Unit Zoning Certificate Prior To Receiving A Permit.

They often make it impossible for homeowners to rent out their ADUs on a short-term basis by prohibiting them from being occupied for fewer than 30 days.

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As the best Bathroom Contractor in the San Francisco East Bay, we have over 20 years of experience transforming homes and living spaces. We specialize in full-service home remodeling, kitchens, bathrooms, room additions, home offices, garage conversions and ADU’s. Say “Hello!” to the home you’ve always wanted. Partnering with our contracting team will deliver amazing results with less stress. Discussing realistic timelines, setting expectations, working within your budget and having open communication keeps anxiety low and everyone – especially you – happy! Check out our portfolio for examples of recent custom work. Are you ready to get started? Your vision. We build it. Contact us today to get started!