A project of the Santa Clara County Planning Collaborative

A project of the Santa Clara County Planning Collaborative

ADU 101

Let's start at the beginning

What is an ADU?

Accessory dwelling units (ADUs) come in many shapes and sizes but are always a self-contained home that is smaller than the main house and legally part of the same property. 

They must have a kitchen, bathroom, and place to sleep, and can range from small efficiency studios to 1,000-square-foot homes with multiple bedrooms. ADUs are also often called granny flats, backyard cottages, in-law units, or converted garage or basement apartments.

HOW LONG DOES IT TAKE?

ADU Project Timeline

Building an ADU is an investment of time as well as money. Most projects take one to two years to complete, with interior conversions being the fastest.

Types of ADUs

There are many different types of ADUs:

DETACHED
New freestanding structure separate from the main home, like a backyard cottage

ATTACHED
New structure (may include some converted space) sharing at least one wall with the main home

CONVERSION
Converted existing space in the main home or on the property (bedroom, basement, detached garage

JADU
A type of conversion up to 500 square feet within the main home (existing or proposed)

MULTI-FAMILY
Any type (except JADU) that is part of a multi-family building (existing or proposed)

Two Approaches to ADU Construction

Site-Built: A traditionally constructed ADU is designed and built specifically for your preferences and property and built on-site (“stick-built”). This option allows for a lot of customization and smaller changes to be made throughout the construction process.

Site-Built

Modular/Prefab/ Manufactured

Modular/Prefab/Manufactured: These ADUs are partially or mostly built in a factory, then shipped to your site to be put together. Using these designs can save time and be more straightforward, but they also typically offer less customization and can be difficult in permitting. Note that not all banks will finance these ADUs.

FAQs

Here are a few of the most frequently asked questions about ADU basics:

This site walks you through each part of the ADU process, from gathering initial inspiration and learning what you can build through construction and becoming a landlord or moving in.

You can also use our Process-At-A-Glance resource for an overview of the process and some initial issues to consider as you get started.

本网站将引导您了解 ADU 过程的每个部分,从收集最初的灵感和了解您可以建造什么,到建造、成为房东或搬入新居。

您还可以使用我们的 “流程概览 “资源,了解流程概述以及开始时需要考虑的一些初步问题。

該網站將引導您完成ADU流程的每個部分,從收集最初的靈感到瞭解您可以通過施工建造什麼,成為房東或搬入。

您還可以使用我們的 流程概覽 資源來概述流程以及入門時要考慮的一些初始問題。

Este sitio le guía a través de cada parte del proceso de ADU, desde la búsqueda de inspiración inicial y aprender lo que usted puede construir a través de la construcción y convertirse en un propietario o mudarse.

También puede utilizar nuestro recurso “El proceso de un vistazo ” para obtener una visión general del proceso y algunas cuestiones iniciales que debe tener en cuenta al empezar.

यह साइट आपको एडीयू प्रक्रिया के प्रत्येक भाग के माध्यम से चलती है, प्रारंभिक प्रेरणा इकट्ठा करने और सीखने से कि आप निर्माण के माध्यम से क्या बना सकते हैं और मकान मालिक बन सकते हैं या आगे बढ़ सकते हैं।

आप प्रक्रिया के अवलोकन के लिए हमारे प्रोसेस-एट-ए-ग्लांस संसाधन का भी उपयोग कर सकते हैं और शुरू करते समय विचार करने के लिए कुछ प्रारंभिक मुद्दों पर विचार कर सकते हैं।

Trang web này hướng dẫn bạn qua từng phần của quy trình ADU, từ việc thu thập cảm hứng ban đầu và tìm hiểu những gì bạn có thể xây dựng thông qua xây dựng và trở thành chủ nhà hoặc chuyển đến.

Bạn cũng có thể sử dụng tài nguyên Process-At-A-Glance của chúng tôi để biết tổng quan về quy trình và một số vấn đề ban đầu cần xem xét khi bạn bắt đầu.

Accessory Dwelling Units (ADUs) come in many shapes and sizes but are always a self-contained home that is usually smaller than the main house and legally part of the same property. They must have a kitchen, bathroom, and place to sleep, and typically range from studios under 500 to 1,000-square-foot homes with multiple bedrooms.

Junior Accessory Dwelling Units (JADUs) are within the footprint of your home (or attached garage) and less than 500 square feet. They can share a bathroom with the main home and/or have an efficiency kitchen (generally a sink, smaller appliances, and counter) Construction costs for JADUs are typically much lower. In most cases, the property owner must live on site in either the main home or the JADU.

State law now allows homeowners to have both a JADU and a regular ADU on their property.

附属住宅单元 (ADU) 有多种形状和大小,但都是独立的住宅,通常比主住宅小,在法律上属于同一房产的一部分。 这些房屋必须有厨房、浴室和睡觉的地方,面积一般从 500 平方英尺以下的单间到 1000 平方英尺的多卧室房屋不等。

初级附属住宅单元 (JADU) 位于住宅(或附属车库)的占地面积内,面积小于 500 平方英尺。 它们可以与主住宅共用一个卫生间和/或有一个高效厨房(一般只有一个水槽、较小的电器和台面)。 在大多数情况下,业主必须住在主住宅或 JADU 内。

现在,州法律允许房主在自己的房产上同时拥有一个 JADU 和一个普通的 ADU。

附屬住宅單元 (ADU) 有多種形狀和大小,但始終是一個獨立的房屋,通常比主屋小,並且在法律上屬於同一財產。 他們必須有廚房、浴室和睡覺的地方,通常範圍從 500 平方英尺以下的工作室到 1,000 平方英尺的多間臥室的房屋。

初級附屬住宅單元 (JADU ) 位於您家(或附屬車庫)的佔地面積內,面積小於 500 平方英尺。 他們可以與主屋共用一個浴室和/或有一個高效的廚房(通常是水槽、較小的電器和櫃檯) JADU的建築成本通常要低得多。 在大多數情況下,業主必須住在主屋或JADU的現場。

州法律現在允許房主在其財產上同時擁有JADU和常規ADU。

Las viviendas accesorias (ADU, Accessory Dwelling Units) tienen muchas formas y tamaños, pero siempre son viviendas independientes que suelen ser más pequeñas que la casa principal y legalmente forman parte de la misma propiedad. Deben tener cocina, baño y un lugar donde dormir, y suelen ir desde estudios de menos de 500 a viviendas de 1.000 pies cuadrados con varios dormitorios.

Las unidades de vivienda accesorias menores (JADU) se encuentran dentro de la huella de su casa (o garaje adjunto) y menos de 500 pies cuadrados. Pueden compartir un cuarto de baño con la vivienda principal y/o tener una cocina eficiente (generalmente un fregadero, electrodomésticos más pequeños y una encimera) Los costes de construcción de las JADU suelen ser mucho más bajos. En la mayoría de los casos, el propietario debe vivir en la vivienda principal o en la UJI.

La ley estatal permite ahora a los propietarios tener tanto una JADU como una ADU normal en su propiedad.

Benefits for Owners and the Community

Building and renting an ADU is truly a community service — ADUs often provide homes for the local workforce and young families who have difficulty finding local housing that meets their needs.  

For homeowners, there are many reasons to build an ADU — keeping multiple generations of family together on the same property, financial security, flexibility over time, and many others.

A HOME AS YOU AGE for a caregiver or an accessible and comfortable option for aging adults

MULTIGENERATIONAL HOUSING for adult children, aging relatives, or loved ones with special needs

RENTAL INCOME for retirement, savings, or a rainy day

SAFETY with an extra set of eyes on the property day-to-day or when you’re away

ENVIRONMENTAL BENEFITS of small-scale living and reduced commutes for workers

AFFORDABLE HOMES for the local workforce and young families

Are you ready to ADU?

We have resources to help you at every step of the way, from initial thoughts through move-in.

Let's do this!

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