900 East Main Street, Suite 109

Grass Valley, CA 95945

530-648-4232

1250 East Ave #10

Chico, CA 95926

530-715-7184

Accessory Dwelling Units (ADUs)

Welcome to our ADU information page! We have gathered our information and plans related to ADUs and compiled it all here! Granny Flats, Mother-in-law quarters, tiny homes and backyard units are all considered to be Accessory Dwelling Units (ADUs).

Jackson & Sands Engineering, Inc. provides plan designs, engineering, and planning consultations to help get you started with building an ADU, regardless of where you are located within California. 

We are happy to work with you in creating a custom design to fit your property and needs or providing prepackaged designs that can save you both time and money (as well as renting the unit out sooner!).
We’re excited to help you with your housing solutions. Drop us a quick note today and let us know where you live and what types of housing opportunities you are searching for.

Plans Available for IMMEDIATE Download!

We have dozens of plans with multiple options developed to help reduce the time and effort required to get YOU an ADU! Options include different sizes, roof styles, varying architectural features, Universal Design layouts, and more! Furthermore, these plans can be adapted to your local jurisdictional requirements.

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Download Your Free Plan!

Please fill out the form below to download your free plans. After you submit the form, please wait for the download page to load as it may take a few seconds. If your browser does not let the download page load, please email us directly for the plans at

Why an ADU

Generally, ADUs can provide an economical housing solution to many of your housing problems!
ADUs can serve multiple purposes, from providing housing opportunities to aging family members while still maintaining privacy to providing long term (and in many jurisdictions short term) rental income.

ADUs can provide as much living space as apartments or condominiums, and can be well suited for all age groups, from young adults to seniors and everyone in between! Additionally, ADUs have become popular with empty nesters ready to down size, but not ready to leave their beloved property and/or neighborhood.

ADUs can provide much needed passive income by creating rental units on property you already own!

How to Start your ADU today!

Download our accessory dwelling unit plans and see if there’s a perfect match for you. If there’s not, that’s OK! We can develop a custom plan for YOU! Set up a FREE, no obligation appointment with us to discuss your backyard cottage or ADU project.

What our Clients are Saying

Articles Related to ADUs

Here at Jackson & Sands Engineering, Inc, we have developed many resources for you in your pursuit to build an Accessory Dwelling Unit, ADU, granny flat, backyard cottage, etc. We have answered many FAQs on the subject matter, including questions about solar and size of ADU requirements. We have added a guide to walk you through what size ADU you could place on your property. If you’re new to building and landlording, we have some great advice for what to expect in contracting . We even sat down with a real estate professional to discuss the value an accessory dwelling unit or granny flat could add to your property. If you had considered adding an ADU to your property in the past, and was told you could not, legislation that went into effect in 2020 could allow you to add that backyard cottage now! We have defined some ADU terms and provided information on what the energy code requires of your mother-in-law quarters.

Permit Ready Plan Programs

Jackson & Sands Engineering, Inc. is proud to be a part of the permit ready programs various jurisdictions are putting together. We are the trusted designer for many Jurisdictions, having completed permit ready ADU and small home designs for the following:

  • City of Chico
  • City of Citrus Heights
  • City of Grass Valley
  • City of Lathrop
  • City of Nevada City
  • City of Orland
  • City of Winters
  • Happy Camp (Siskiyou County)
  • Nevada County
  • Placer County
  • Sierra County
  • Town of Paradise
  • Town of Truckee
  • Yuba County