Accessory Dwelling Units

Accessory dwelling units, ADU’s, second dwellings, or the more affectionately known Granny Units are a great way to help the broad need for housing in our community.  ADU’s typically range from 400-1,200 square feet and can either be attached or detached to the main house.

Below is some information we hope you find helpful.  There is more information than we can clearly explain on a page so we are happy to walk you through the process. Send us an email or call our office to see if an ADU is right for you.


This is a sample of our 3 most economical layouts.  However, we can customize and create a floor plan for your space if needed!

488 Square Feet, Approx Cost $125k

632 Square Feet, Approx Cost $160k

858 Square Feet, Approx Cost $210k

Boomerang Kids

A higher percentage of kids 18-34 are moving back home to live with their parents.  High cost of living and student debt have forced the younger generations to seek alternative living arrangements.  An ADU provides a low cost rental.

Getting old or knowing someone who is

Let’s face it, none of us are getting any younger.  Granny units are a great way to downsize from a 2 story larger home to smaller single level living.  Alternatively, they can be used as a living arrangement for aging parents who need to be closer to care.  Building new construction allows for accessibility items to be incorporated including wider doorways for walkers, curbless showers, and side by side appliances for less bending and lifting.

Community Benefits

Second units can help address the housing challenges in our community by adding homes that are generally more affordable.  This provides workforce housing and preserves diversity and community character.


The process varies by jurisdiction but generally follows the same procedure.  California law has made it even easier and eliminated a number of barriers to entry including reduced parking, lower fees, and quicker approvals.  Information for Accessory Dwelling Units can be found here

Santa Rosa Accessory Dwelling Unit Info here

Sonoma County ADU info here

Healdsburg Second Dwelling Unit info here 

Feasibility Analysis

Typically this starts with a look through online resources like Google Maps and APN maps to make sure the unit will fit.  Secondly, if the unit will fit, does the budget meet the clients expectations.  We offer a range of options to try to accommodate each budget.

Permits and Approvals

The next step is to obtain approval by submitting construction documents to the jurisdiction.  Our team will take care of that entire process.  Clients can save considerable time and money by reusing an existing plan.

Time to Build!

You’ll work with our team to select all the interior and exterior selections.  Then we will begin production in our factory while the team prepares the site for the core.  Construction time can take as little as 30 days with all the right pieces!

Modular Benefits

hybridCore Homes is proud to be a better way to build.  Each individual project will be able to capitalize on varying degrees of benefits, often beating conventional construction by a long shot.

Fraction of the Construction Time

Fraction of the Construction Time

By completing most of the home in the factory, a hybridCore significantly cuts the construction time in half.  This means less intrusion in your personal space and quicker time to market for rental properties.

Fixed Costs

Fixed Costs

Once we have the plans finalized we can provide a total cost of construction.  That means you know exactly how much your project will cost and can make the necessary decisions based on the budget.

Efficient Green Building

Efficient Green Building

Factory efficiency means that each piece of lumber, metal, or materials is recycled and reused whenever possible to eliminate waste.

Industry Standard Warranty

Industry Standard Warranty

Our Cores are backed by a one year service warranty for appliances, wiring, and plumbing.  A ten year structural warranty backs the bones of the house.

Get your project started

Interested in learning more? Send us a message and we’ll get in touch.

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