Tag Archives: Where can an ADU be built

5 Decisions to Make Before Starting Your ADU Construction

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This entry is part 2 of 11 in the series Accessory Dwelling Unit

 

 

If you want a source of passive income and to do a community service at the same time, a rare opportunity to be sure, there’s no better option than constructing an ADU (accessory dwelling unit) on your property. This is Honolulu’s best answer to the increasingly pressing crunch for affordable housing and while there are some very specific rules, it’s a great chance for current homeowners to significantly increase the value of their property, provide a new home to family or renters in need, and enjoy the excitement of a new project literally in your backyard. However, before you start putting up timbers, there are a few important decisions you need to make.

1) Is the ADU for You, Family, or Renters?

The reason you’re building an ADU will shape every other decision you make, so you might as well start at square one. ADUs can serve a number of interesting, helpful, and profitable purposes depending on how they are used. If you (the homeowner) plan to move into the ADU and leave the main house for the family or high-dollar renters, the design should be fit to your personal needs. If the ADU is to house an overflow of family, consider their preferences and look into ohana housing instead, which has fewer regulations but isn’t as versatile if the family moves out. Finally, if you’re planning for renters, you’ll want the ADU to be as welcoming as possible for anyone who might move in.

2) Would it be better Attached or Detached from the Main House?

You may not have realized it, but ADUs can absolutely be built as an attachment to your main house. In some cases, this may be the only way to achieve the required number of parking spots or fit the second dwelling onto an oddly shaped lot. That said, attached ADUs are more ideal for the family as you’ll be living in close proximity, along with sharing a wall and possibly a door to the main house. For ADUs you plan to rent or plan to eventually be able to rent, later on, it would be better to build a detached dwelling for added privacy and personal space.

3) Are You Prepared for a Very Small Dwelling?

ADUs come with a maximum size restriction depending on the square footage of your lot, and these can be pretty darn small. If your lot is between 3,500 and 5,000 sq ft, your ADU could have a maximum size of 400 to 800 sq ft. That may be smaller than you’re imagining. With 400 sq ft, there’s usually enough room for one bedroom with a full to queen sized bed, a compact kitchen/living/dining area, and a small bathroom. Once you know how big an ADU you can build, take a walk through a few models and existing homes around the same size to really get a feel for the functional size of the home. That said, people have reported living comfortably in less than 200 sq ft.

4) Can You Convert an Existing Accessory Structure?

If you have a large shed or well-built workshop already on your property, there’s a chance that you might be able to convert this into all or part of your new ADU. For this to be a viable option, the accessory structure needs to be sturdy and capable of being upgraded to good quality living conditions. You’ll need insulation, real walls and floors, a kitchen, and a bathroom along with the necessary power, water, and possibly gas connections. It may just be easier to build a new structure, perhaps even making room by knocking down the old shed rather than repurposing it.

5) Do You Want to Go “Off-Grid”?

One of the really nifty options for a brand new ADU is the ability to go ‘off-grid’. What this means for most is solar panels. Big ones, with enough battery power to ensure that the lights and water heater work at night as well. You can even install a rainwater collection and filtering system but we suggest keeping the water pipes even if your ADU is power independent. An off-grid ADU will cost a little more to make but for the rest of its life will add nothing to the power bill. If you’ve got the money to invest and love the idea of renewable energy, this could be a great ADU choice that will, incidentally, also raise its value as a rental property. While you’re at it, throw some solar on the main house, too.

Here at Owner Built Designs, we specialize in making your Honolulu ADU dream a reality. For more helpful tips on designing the perfect ADU for you, your family, and your property contact us today!

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The 9 Basic Requirements for Building an ADU in Hawaii

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This entry is part 10 of 11 in the series Accessory Dwelling Unit

 

Since the dawn of property ownership, people have been building smaller dwellings near their pre-existing homes. In Australia, they call them Granny Flats, in certain parts of the continental US, they’re called Mother-in-Law houses and here in Hawaii, the official term is ADU, short for Accessory Dwelling Unit. Like the acronym says, these are little homes that act as complete residential unit accessories to a main house on a shared property. Theoretically, anyone can build an ADU simply by making a nice addition or building with a kitchen, bedroom, and bathroom but officially there are certain legal guidelines for an approved ADU construction. Before you break out your carpentry tools or call a contractor, make sure your home and plans conform to the 9 basic requirements for building an ADU.

1) Proper Zoning

Zoning in Hawaii and knowing your exact zone can be a little tricky and ADUs can only be built in six specific zones. Before even thinking about building one of these tiny separate houses, make sure to check your lot’s zone by address and ensure that it matches one of the following:

  • R-3.5
  • R-5
  • R-7.5
  • R10
  • R20
  • Country District

2) Lot is At Least 3,5000 Square Feet

To ensure that there is plenty of room for your ADU, anyone who wants to build one needs to have a house lot that reaches at least 3,500 square feet of space. Fortunately, your original house is allowed to sit on some of it. Rather than breaking out the incredibly long measuring tape, you can check your lot’s size online to figure out if you qualify. Bigger is always better, and you’ll find out why with point nine.

3) Lot is Not Landlocked

To build an ADU, your lot will need to actually make contact with the road. Due to certain access requirements, a landlocked lot cannot hold an ADU. However, you can have an ADU if your lot is connected via driveway to the road by way of an easement through another closer lot. Flat lots are also perfectly fine.

4) Lot Has One Current Dwelling

You cannot build an ADU unless there is only one complete dwelling on your lot. This means that duplexes, apartment buildings, and lots that already have two or more homes on them cannot build an ADU. However, renovated apartments above the garage or in the basement are just fine as long as they’re not legally a second dwelling.

5) Owner or Family Lives On the Lot

To qualify for ADU construction, the homeowner or at least one member of their family needs to live on the lot when the ADU is complete. This means they can either live in the main house or the ADU based on preference, as long as the owner or a family member is in residence. You are allowed to rent out whichever building you’re not going to live in.

6) Record Your Covenants

When you do build an ADU, you are required to record covenants with the land with either the Bureau of Conveyances or the Land Court of the State of Hawaii or both. This ensures that you will never sell the ADU separately from the rest of the property and the lot cannot be subdivided into two separate properties. There are also other related rules in the Declaration of Restrictive Covenants.

7) No ADU Covenant Restrictions

Check any private covenant signed for your land to ensure that it doesn’t prohibit an ADU. If you have already agreed not to build one, starting construction now would be both illegal and quite silly. However, you may not be aware that the prohibition exists to make sure to check with your HOA to be sure.

8) Room For One More Parking Space

An ADU is officially an entirely separate second dwelling and because of this, it’s expected that the resident is likely to have their own car. Therefore to build a legal ADU, you’ll need room within the lot’s parking areas for one more parking space than your lot’s minimum spaces unless the edge of your property is within a half mile of a rail station.

9) ADU Plans Meet Maximum Size

The maximum square foot size of your ADU is limited by the square footage of the lot itself. For a lot at the minimum size of 3,500, your ADU can only be 400 square feet. For just under 5K, it can be up to 800 sq-ft, and for lots above 5K, you can have a much larger ADU.

By the end of this list, you should have a fairly good idea of whether or not you’re legally allowed to build an ADU on your property in addition to your single-family home. If you do decide that an ADU is right for you, your lot, and your family contact us today! We’ll be happy to help you figure out the next steps.

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What’s the 411 with Hawaii ADUs?

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This entry is part 4 of 11 in the series Accessory Dwelling Unit

Honolulu‘s mayor signed a provision for accessory dwelling units (ADUs) in September 2015. Now, qualifying owners of freestanding, single-family homes have a new way to generate revenue – by renting a secondary residence situated on their property. ADUs are a response to the Mayor’s Affordable Housing Strategy, developed in response to the shortage of inexpensive rental housing on the island.

It is important to understand that ADU approvals, design and permitting requires adherence to very specific standards. Honolulu’s Department of Planning and Permitting (DPP) discusses frequently asked questions about permitting related to ADUs at this link.

Frequently Asked Questions

Here we discuss some of the most common questions about ADUs:

Q: What is an ADU?

The DPP specifically defines an ADU as “an accessory or second dwelling unit, including its own kitchen, bedroom, and bathroom facilities, attached or detached from the primary dwelling unit on the zoning lot.”

Importantly, an ADU is subordinate to the primary residence. However, it does not have to be detached from the existing home. While many ADUs feature new construction, it is possible to remodel some existing single-family homes to create them. However, every ADUdesign must include a kitchen, a bathroom, and at least one bedroom. Current building codes apply to such renovations/additions.

ADUs are usually found to the rear or side of the existing dwelling, and they are subject to strict size limitations. For example, an ADU on a lot from 3,500 to 4,999 square feet (SF) in size must be 400 SF or smaller. On a 5,000+ SF lot, ADUs can be up to 800 SF in size.

Q: In what ways are ADUs important?

ADUs help address Honolulu’s chronic housing shortage, and they provide aging residents a convenient way to downsize.

Relieve Housing Shortage – It is no surprise to those living in Honolulu that the cost of living is substantial. In fact, one site ranks Hawaii’s capital 4th out of 66 U.S. cities, although it is still 14 percent less expensive to live in Honolulu than New York City. However, with rent for a 900 sqr-ft furnished apartment averaging more than $2,000 per month, and utilities averaging more than $250/mo, many workers struggle to find affordable housing. ADUs address this need.

Aging in Place – ADUs also offer aging homeowners a unique opportunity to downsize while remaining on the very same property that likely hosted endless parties and other memorable family events over the years. A senior can “age in place” by eventually moving out of the larger primary residence and into the smaller ADU. The homeowner can then rent out the larger home to generate potentially substantial rental income.

Q: Where can an ADU be built?

Zoning is crucial to ADU development. Although there is an important caveat, an ADU may be built on lots zoned R-3.5, R-5, R-7.5, R-10 or R-20. Construction of an ADU is also possible in a Country District with a lot measuring 3,500 SF. The caveat? Even when a lot is appropriately zoned, there must be adequate utility infrastructure in place, and the ADU cannot conflict with existing restrictive covenants. This effectively eliminates ADUs from consideration in master planned communities or those with homeowners associations. The ADUmust also comply with any land use provisions that come with the specific zoning.

When eligible, only a single ADU is possible on a lot with one single-family home on it. This excludes lots with duplex homes as well as those with an existing ohana unit or guest house.

Q: How do ohana units and ADUs compare?

These two kinds of living spaces differ as to maximum size, occupancy, and parking. ADUs are subject to size restrictions, while ohana units are not. Only family members may live in an ohana unit, while there is no such restriction with an ADU. Finally, ohana units must have two off-street parking spaces, while ADUs only need one (those less than a half-mile from a rail station have no parking requirement).

It is also important to note that the property owner (or appropriate relative) must live in the primary residence or the ADU. Exceptions exist for serious illness or active military deployment. Leases for ADUS must be at least six months long. When a property is sold, the primary residence and the ADU must be sold together.

Owner Built Design, LLC is a key resource when you are looking into an ADU. Let me put my decades of experience to work for you. Please contact me today.

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