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April 19, 2024

ADU Laws and Regulations in Boise - 2024

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Overview of ADU Laws in Boise

In Boise, Idaho, the accessory dwelling unit (ADU) regulations are crafted to maintain the character of neighborhoods while providing options for increased housing. These structures, often referred to as backyard cottages, granny flats, or in-law apartments, are subject to various controls under the City of Boise's zoning laws.

Per Boise's guidelines, ADUs must adhere to the dimensional standards of the zoning district they are located in. This includes compliance with the International Building Code. The integration of ADUs aims to reflect the visual essence of single-family homes and complement existing neighborhood designs.

The project requirements mandate adherence to the City of Boise's permit procedures, ensuring compliance with local regulations. Additionally, the design must harmonize with the surrounding neighborhood's aesthetics, emphasizing compatibility. Owner occupancy is a key criterion, typically requiring the primary property to be inhabited by the owner. Furthermore, size limitations are contingent upon specific zoning regulations, varying accordingly.

It's worth noting that these regulations can influence property value. Constructing an ADU can come with various costs, potentially ranging from $150,000 to $325,000, factoring in the size and finishes. Moreover, adjustments to Boise's zoning code have led to a boost in ADU permit applications.

Recent updates have propelled a surge in permits, signaling a shift towards more dense, affordable housing options. State and city regulations intend to address the growing demand for housing while preserving the cityscape. Consequently, the City of Boise's evolving stance on ADUs demonstrates a forward-thinking approach to urban development and diversity of housing within the State of Idaho.

Types of ADUs Permitted in Boise

In Boise, a range of Accessory Dwelling Units (ADUs) is permitted, broadening the spectrum of housing options. The city recognizes several types of ADUs, crafted with specific design standards to integrate seamlessly into residential areas. Below is an outline of permissible ADU types.

  • Detached ADUs: Stand-alone structures, sometimes referred to as granny units or alley homes, they are separate from the primary residence.
  • Attached ADUs: These are built as an extension of the main home, such as in-law suites or mother-in-law suites.

Boise mandates that ADUs, regardless of type, must maintain the design and appearance of a single-family dwelling, ensuring a consistent aesthetic in neighborhoods.

The types of Accessory Dwelling Units (ADUs) include Detached units, which are independent structures located in the backyard or side yard, Attached units, which share a wall with the main house and are often extensions or conversions, and Above Garage units, built atop existing garage spaces, typically maintaining the same footprint as the garage below.

Boise’s policy acknowledges the value of ADUs in providing affordable housing and increasing density. The city’s regulations aim to encourage the development of ADUs, all while maintaining the character of residential neighborhoods.

Size and occupancy restrictions apply and are dictated by the underlying zoning district rules. ADUs provide a vital role in the urban housing landscape, offering alternatives such as tiny homes for individuals seeking a smaller footprint.

For homeowners interested in developing an ADU on their property, they must abide by the city’s dimensional requirements and adhere to the provisions of the International Building Code as stipulated in a handout released by the City of Boise.

Eligibility and Permitting Process in Boise

Navigating the ADU regulations in Boise requires understanding the stringent eligibility criteria and the multifaceted permitting process. Homeowners must adhere to the guidelines set by the city to ensure lawful and swift approval for their ADU projects.

Eligibility Requirements

To be eligible for an ADU in Boise, homeowners must verify that their property meets specific zoning code regulations. The lot size is a primary consideration, as it dictates the dimensions and placement of the ADU. There are also setback requirements that ensure the unit is situated a proper distance from property lines. Additionally, occupancy requirements must be followed; typically, the homeowner must reside in either the primary or accessory dwelling. It's also crucial to check with any homeowners' associations (HOAs) that may have further restrictions on ADU construction.

Application and Approval

The application process for an ADU permit in Boise starts with submitting the appropriate documents to the City of Boise planning department. This submission must demonstrate compliance with all city regulations, including the updated zoning code provisions. The City thoroughly reviews submitted materials, and the homeowner may need to attend a hearing or adjust their plans based on feedback from the city officials. Once the application meets all the criteria, preliminary approval is granted, subject to the issuance of building permits.

Building Permits

Upon receiving city approval, homeowners must obtain the necessary building permits. These are essential for legal construction to commence and ensure that all building standards and safety requirements are met. The permit process requires detailed construction plans and may involve the payment of fees as dictated by the state and local ordinances. Building permits are mandatory and serve as a final checkpoint before the physical work on the ADU can begin. Compliance with these regulations safeguards the interests of the homeowner, the community, and the City of Boise.

Building and Design Standards in Boise

In Boise, the standards for building and designing an Accessory Dwelling Unit (ADU) revolve around ensuring the structure is safe, aesthetically consistent with the existing community, and compliant with size and placement regulations.

Construction Requirements

Construction of ADUs in Boise must adhere to the 2018 International Building Code (IBC). This includes considering ground snow load and roof snow load specifications to ensure structural stability. Costs associated with ADU construction have risen due to factors such as labor shortages and material costs. Current figures indicate that an ADU may range from $150,000 to $325,000. Furthermore, if the ADU is intended for rental purposes, Boise building codes dictate that the proper permits are obtained and that the construction is completed according to safety standards.

Design and Aesthetic Standards

ADUs within Boise must be designed to maintain the character of the neighborhood, especially within historic districts. They are required to resemble the primary dwelling in design, thereby necessitating a careful selection of materials and colors. ADUs should also follow guidelines pertaining to the historic district to preserve the district's unique identity and heritage.

Foundation and Size Limits

ADUs in Boise are subjected to specific foundation and size limits to ensure they fit appropriately within the property. They must not exceed 700 square feet or ten percent of the lot area, whichever is smaller. Also, they should meet setback requirements from the property lines and not interfere with any existing driveway. The foundation requirement assures that ADUs are permanent, safe structures that complement the main residence.

Financial Considerations in Boise

When planning to build an Accessory Dwelling Unit (ADU) in Boise, homeowners should prepare for several financial aspects, including the cost of construction, potential funding, and mandatory fees. Awareness of these financial factors is crucial for accurate budgeting and maximizing the benefits of creating affordable housing.

Cost Estimation

The cost of constructing an ADU in Boise can be considerable. Factors affecting this cost include size, design, amenities, and choice of finishes. Homeowners should anticipate an all-in cost ranging from $150,000 to $325,000 according to a complete guide for homeowners. Precise estimation is key to ensure financial readiness for the project ahead.

Funding and Grants

Homeowners looking to build ADUs in Boise might find financial support through local funding opportunities or grants aimed at developing affordable housing. It is essential to research and apply for any available programs that might alleviate the financial burden. The City of Boise may offer resources or initiatives that encourage ADU construction to boost housing options.

Impact Fees

Boise homeowners also need to consider impact fees, which are charges imposed by the city to fund the infrastructure required to support the new housing unit. These fees cover the additional use of city services like water, sewer, roads, and parks. Details on impact fees and regulations can be acquired by reviewing the Boise City Code. It's important for homeowners to factor these costs into the overall budget for the construction of an ADU.

Usage Restrictions and Opportunities in Boise

In Boise, Accessory Dwelling Units (ADUs) have specific usage restrictions and also present various opportunities for homeowners. These regulations ensure that ADUs contribute positively to the cityscape and community, while also providing avenues for rental income and flexible living arrangements.

Rental Regulations

Boise's regulations permit homeowners to use ADUs for long-term rental purposes, providing a source of rental income. However, homeowners must be aware that the city discourages the use of these units for short-term rentals, such as those often listed on platforms like Airbnb. This approach prioritizes housing availability for residents over tourist accommodations.

Owner Occupancy

The owner occupancy requirement specifies that the owner of the property must reside in either the main dwelling or the ADU. This rule is instituted to maintain neighborhood character and prevent absentee ownership, which could lead to less-maintained properties and a shift away from long-term community residency.

Non-Residential Uses

While primarily intended for residential use, ADUs in Boise can accommodate non-residential functions such as a home office or studio. Constraints, however, are placed to prevent the operation of more impactful businesses. ADUs must also provide at least one parking space unless they qualify for an exemption, ensuring that the increased density does not adversely affect street parking availability.

Moreover, although ADUs are seen as a step towards increasing affordable housing, they are not without their own restrictions, such as size limitations that define them as tiny homes. These rules are designed to integrate ADUs seamlessly into existing neighborhoods, balancing the benefits of increased density with maintaining the character and livability of the city.

Local Community Impact in Boise

Boise's recent update to its zoning regulations has resulted in a significant uptick in permits for accessory dwelling units (ADUs), influencing various aspects of the community. This regulatory adjustment is seen as a step toward mitigating the affordable housing crunch that many residents face.

Planning and Growth in Boise With ADUs now more feasible to build, the planning departments have seen a steady influx of permit applications. This change aligns with the city's growth plans, providing additional housing without significantly altering existing neighborhoods.

Affordability Concerns The introduction of ADUs offers a less costly alternative to traditional housing options. The costs associated with constructing an ADU vary but tend to be more affordable, lending a hand to alleviate the housing pressure in Treasure Valley.

Impact on Homeowners and Property Values Homeowners now have the opportunity to add value to their property by constructing ADUs. This can serve as a potential source of rental income or a means to house extended family, which may, in turn, have a stabilizing effect on the community.

Community Response Reactions among the Boise community have been mixed. While many acknowledge the benefits ADUs bring to affordability and housing availability, concerns over increased density and its effect on neighborhood character persist.

The full impact of the zoning changes within Boise's housing landscape will continue to unfold, as property owners and city officials navigate these new opportunities for growth and development provided by accessory dwelling units.

Construction and Professional Services in Boise

When embarking on the construction of an Accessory Dwelling Unit (ADU) in Boise, homeowners must make informed decisions regarding professional services, including selecting a reputable contractor and effectively managing the construction process.

Choosing a Contractor

Homeowners should rigorously vet potential contractors for their ADU project. It is advisable to confirm that the contractor is licensed to perform residential construction in Boise. Homeowners may want to review past projects to gauge quality and reliability. Obtaining multiple bids from different contractors is beneficial to ensure costs reflect the current market rates for constructing an ADU.

  • Check licensing through Boise's official channels.
  • Examine the contractor's portfolio of completed ADUs.
  • Obtain at least three bids for comparison.

Navigating Construction Projects

Once a contractor has been selected, it’s essential to understand the construction timeline and the roles of various parties involved. Clear communication with the general contractor is key, as they will coordinate with builders and subcontractors to keep the project on track. Homeowners should be prepared for potential delays due to factors like weather or material availability.

  • Establish a timeline with milestones for project completion.
  • Monitor progress through regular updates from the general contractor.
  • Anticipate possible delays and maintain flexibility.

Ancillary Benefits and Uses in Boise

Accessory Dwelling Units (ADUs) in Boise provide valuable additional living space and flexibility, catering to the diverse needs of homeowners and contributing to the array of affordable housing options. ADUs often serve as self-contained living quarters, which can be utilized in various ways that support the dynamics of today's modern households.

Additional Living Space

ADUs provide homeowners with the ability to expand their living area without having to purchase a larger primary dwelling. This space can be utilized for many purposes, including tiny homes for adult children returning home or in-law suites for aging parents. Offering an alternative to larger, more expensive housing, ADUs are an efficient way to maximize residential properties and support relatives who may benefit from close proximity while maintaining their independence.

Flexible Housing Options

The incorporation of ADUs as part of Boise's residential landscape has introduced a layer of flexibility not just for homeowners, but also for the community at large. Homeowners may use these units for affordable housing solutions, creating opportunities for rental income or accommodating a growing family. For homeowners looking to assist adult children or care for aging parents, ADUs present a separate, yet nearby, living solution that balances privacy and accessibility. As the housing needs of Boise's residents evolve, ADUs serve as a versatile tool in addressing these changes.

Regulatory and Legal Framework in Boise

The legal complexities of Accessory Dwelling Units (ADUs) in Boise are framed by specific local legislation and adherence to state-enforced building codes. These regulations are pivotal for homeowners and builders to navigate the process of creating ADUs legally and effectively.

Local Legislation

In Boise, local legislation dictates the specific requirements and regulations for ADUs. Per the City of Boise, these dwellings are intended to increase affordable housing options and maintain the character of neighborhoods while allowing for increased density. Key points of Boise's ADU regulations include:

  • Size Restrictions: ADUs must not exceed ten percent of the lot area or 700 square feet, whichever is smaller.
  • Occupancy Limitations: Only one additional family unit is allowed in an ADU.
  • Location Constraints: The ADU must be located on the same property as a single-family home.

It's crucial for homeowners to ensure that their planned ADU conforms to these guidelines. Moreover, navigating Boise's zoning laws requires an understanding of the area's zoning district and the relevant development standards.

State Building Codes

When constructing an ADU, compliance with the State of Idaho building codes is essential. These codes ensure that structures are safe, efficient, and meet a state-wide standard of construction quality. Builders must consider:

  • Building Permits: Successful acquisition of a building permit is reliant on adherence to both state and local regulations. Boise has experienced an increase in permits for ADUs indicating a more accessible process for homeowners.
  • Safety Regulations: Construction plans must meet safety standards covering areas such as egress, fire safety, and structural integrity.
  • Compliance Audits: After construction, ADUs may be subject to inspections to verify compliance with all applicable codes.

Following these guidelines is not just a legal necessity but also a measure to ensure the safety and durability of the ADU. Local municipalities are expected to enforce the state's building codes, but there may be additional municipal requirements or incentives that can impact ADU development.

Frequently Asked Questions

This section addresses common inquiries about the regulations governing accessory dwelling units in Boise, providing clarity on specific rules and recent legislative updates.

What are the current setback requirements for constructing an ADU in Boise?

In Boise, accessory dwelling units must observe setback requirements intended to maintain privacy and open space. These are analogous to other residential structure regulations and can vary depending on zoning designations.

Are there any new developments in the ADU laws and regulations for Boise residents to be aware of?

Recently, Boise has experienced a surge in permits for ADUs, following adjustments to the city's zoning code. With more residents applying for permits, it's clear that awareness of the changes and opportunities they present is crucial for homeowners.

What is the maximum allowable size for an ADU in Boise, Idaho?

Boise city code stipulates that an ADU must not exceed ten percent of the lot area or 700 square feet, whichever is smaller, ensuring that ADUs remain subordinate to the primary residence.

How does the cost of building an ADU in Boise compare with traditional home extensions?

Construction of an ADU in Boise typically incurs a significant cost, influenced by factors such as labor, materials, and design choices. These costs can rival or sometimes surpass those of traditional home extensions, due to the comprehensive nature of creating a fully independent living space.

Can an accessory dwelling unit in Boise be larger than the primary residence on the same lot?

In Boise, the accessory dwelling unit must be smaller than the primary residence. This requirement maintains the property’s single-family nature, while allowing for additional, albeit limited, residential space.

What are the specific ADU zoning requirements for Meridian, Idaho, compared to those in Boise?

The zoning requirements for accessory dwelling units in Meridian differ from those in Boise, with unique conditions on size, location, and owner occupancy. It is essential for individuals considering an ADU in Meridian to review the specific city ordinances for accurate guidance, as regulations can vary even between neighboring jurisdictions.

This post is for informational purposes only and does not serve as legal, financial, or tax advice. Consult your own legal, financial, or tax advisor for matters mentioned here. The information on this site is general in nature. Any description of coverage is necessarily simplified. Whether a particular loss is covered depends on the specific facts and the provisions, exclusions and limits of the actual policy. Nothing on this site alters the terms or conditions of any of our policies. You should read the policy for a complete description of coverage. Coverage options, limits, discounts, deductibles and other features are subject to individuals meeting our underwriting criteria and state availability. Not all features available in all states. Discounts may not apply to all coverages. Steadily is not liable for any actions taken based on this information. If you believe any of this information may be inaccurate please contact us.

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