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Accessory Dwelling Units

During the third series of Community Conversations on Growth, the City shared various proposals to address the need for affordable housing. A key component of this effort is exploring ways to maximize land use to support the creation of additional affordable housing in appropriate locations by amending the development code.

The first area the City is considering changes relates to Accessory Dwelling Units (ADUs).

If you’re unfamiliar with ADUs, they’re a second, smaller dwelling that can be built on property already occupied by a single family home.

While Boise allows ADUs, the City is considering four changes that may remove barriers to affordable housing with minimal impact on existing neighborhoods.

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Increase Maximum Size for ADU's

Currently, ADUs are limited to 600 square feet or 10% of the parcel size, whichever is smaller. The City is considering a slight increase to the 600 square foot cap, while maintaining the 10% limit. This would allow larger ADUs on larger parcels.



Allow More Than One Bedroom in ADU's

ADUs are currently limited to one bedroom. This effectively precludes ADUs as an affordable housing option for a small family. The City is considering removing this restriction, which would allow for more bedrooms, contingent upon the overall size of the ADU.

Eliminate On-Site Parking Requirement

Clarifying that two-bedroom ADUs must have at least one dedicated parking space on-site or on an immediately adjacent street with no exceptions (current requirements of one parking space per ADU can be waived depending on individual situations).

Eliminate Owner Occupancy Requirement

Current regulations require that the property owner reside in either the primary unit or the accessory dwelling unit. The City is considering removing this requirement.

Submit Feedback

To ensure the City’s approach is consistent with the vision of the larger community, we’re continuing to solicit feedback about these items.

Please take time to review each of the four concepts and share any comments or concerns. All feedback will be considered as the City proposes an update to the Accessory Dwelling Unit Ordinance. Additionally, the Planning Team is available to meet in person or over the phone at (208) 608-7086.

Online feedback for ADUs is now closed. Please check back for updates.

Published: January 23, 2019