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California Department of
Housing and Community Development

Adequate Sites Alternative

Government Code Section 65583.1 (a) and (c) allows accessory dwelling units (ADU) and, under prescribed conditions, units that are substantially rehabilitated, converted from market rate to affordable, or where unit affordability is preserved to be counted towards the adequate sites requirement.


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Requisite Analysis

Local governments can employ a variety of development strategies and/or commit to specific programs to address the adequate sites requirement. As provided in Government Code Section 65583.1(a) and (c), in addition to identifying vacant or underutilized land resources, local governments can meet up to 25 percent of the requirement to provide adequate sites by making affordable units available through development of accessory dwelling units, rehabilitation, conversion, and/or preservation.

Accessory Dwelling Units

Under limited circumstances, a local government may credit up to 25 percent of their adequate sites requirement per income category through ADUs based on the number of ADUs developed in the prior housing element planning period whether or not the units are permitted by right, the need for these units in the community, the resources or incentives available for their development, and any other relevant factors, as determined by the department. Nothing in this section reduces the responsibility of a city or county to identify, by income category, the total number of sites for residential development as required.

To rely on ADUs as part of an overall adequate sites strategy to accommodate (a portion) of the regional housing need, the element must include an estimate of the potential number of ADUs to be developed in the planning period based on an analysis that considers the following factors:

  1. the number of ADUs developed in the prior planning period;
  2. community need for these types of housing units,
  3. the resources and/or incentives available that will encourage the development of ADUs; and
  4. other relevant factors as determined by HCD.

The projection of ADUs development must be based on realistic capacity and development trends of ADUs in the previous planning period. In addition, the housing element must describe and analyze factors that could affect ADUs development within the planning period. At a minimum, the element should analyze development standards (i.e., heights, setbacks, minimum unit sizes, lot coverage, parking standards, etc.), what zones allow ADUs (by right), architectural review standards, fees and exactions, and any other components of the ordinance potentially impacting or constraining the development of ADUs.

ADU Affordability: The housing element should also include an analysis of the anticipated affordability of ADUs. The purpose of this analysis is to determine the housing need by income group that could be accommodated through ADU development. ADU affordability can be determined in a number of ways. As an example, a community could survey existing ADUs for their rents and include other factors such as square footage, number of bedrooms, amenities, age of the structure and general location. Another method could examine market rates for reasonably comparable rental properties to determine an average price per square foot in the community. This price can be applied to anticipated sizes for ADUs to estimate the anticipated affordability of ADUs.

Substantial Rehabilitation, Conversion, and Preservation

Under limited circumstances, a local government may credit up to 25 percent of their adequate sites requirement per income category through existing units that will be:

Substantially Rehabilitated: Units to be substantially rehabilitated must result in a net increase in the stock of housing affordable to low- and very low-income households and include the following provisions:

Converted: Converted units are those located on a foreclosed property or in a multifamily rental or ownership housing complex of three or more units that have been converted from non-affordable to affordable rental by acquisition of the unit or the purchase of affordability covenants and restrictions. These units are not to be acquired by eminent domain and must provide a net increase in the stock of housing affordable to low- and very low-income households.

Converted units must be made available for rent at affordable housing costs; not already occupied by low- or very low-income households; and in decent, safe, and sanitary condition when occupied. Long-term affordability covenants (not less than 55 years) apply to these units. Relocation assistance must be provided to any occupants temporarily or permanently displaced and the local government must require that any displaced occupant will have the right to reoccupy the rehabilitated units.

To convert existing multifamily ownership units, the housing element must demonstrate that for each ownership unit converted to an affordable unit and counted under the Alternative Adequate Sites, a new multifamily rental unit affordable to lower-income households will be constructed within the planning period of the housing element. For example, for a community to count the conversion of 10 multifamily ownership units to units affordable to lower-income households, the housing element must demonstrate that at least 10 new multifamily rental units will be produced within the planning period of the housing element. The housing element could describe the number of multifamily units that will be constructed within the planning period to be affordable to lower-income households, identify the date new construction was or is anticipated to be completed, and include a description of the regional housing need allocation credit methodology used to determine affordability. The jurisdiction could also include certificates of occupancy to satisfy this requirement. The number of units affordable to low- and very low-income households that have been constructed must meet or exceed the number of converted ownership units credited against particular regional housing need allocation income categories.
While foreclosed properties converted by acquisition or the purchase of affordability covenants currently qualify under the same conversion provisions for multifamily units, as of January 1, 2015, these units are now also required to demonstrate multifamily rental production as stated in the above paragraph.

Preserved: Units to be preserved at affordable housing costs to lower-income households by acquisition of the unit or the purchase of affordability covenants for the units. Preserved units must meet all of the following requirements:

Units must also be found (via a public hearing) eligible for preservation, with a reasonable expectation that the units will change from affordable to another use during the next five years. When units are identified for preservation, they must be available at costs affordable to persons and families with low- or very low-incomes.

Additional Requirements:

“Committed assistance” exists when a local government has entered into a legally enforceable agreement during the first two years of the housing-element planning period that obligates sufficient, available funds to make identified units affordable and ensures the units will be made available for occupancy within two years of the execution of the agreement. “Net increase” refers only those units that were not provided committed assistance in the immediately prior planning period.

This Alternative Adequate Sites Checklist (DOC) provides guidance in determining whether the provisions of Government Code Section 65583.1(c) can be used to address the adequate sites program requirement. A “yes” answer to the questions means the alternative site program option(s) may be applicable to your community.

Helpful Hints

An assisted housing development is any multifamily rental housing development that receives governmental assistance under any of the following programs: