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what is an ADU? (

An accessory dwelling unit, usually just called an ADU, is a secondary housing unit on a single-family residential lot. There are different types of ADUs. Here at OASYS, we specialize in:

  1. Free-standing new construction sometimes called “granny flats” or “laneway houses”

  2. Garage Replacement construction known as Junior ADUs or JADUs because they are generally 400 sq. ft or smaller.

  3. Home extension or additions known as “bump-out” ADUs that are attached to the existing single family home

why get an ADU?

Our clients are adding ADUs to their properties for so many different reasons, the most common being:

  • live-work space

  • multi-generational living

  • growing families

  • passive income

frequently asked questions

Is my property big enough?

Yes! there is no minimum lot size, as long as you are zoned for single family residences.

Can I build more than one?

Yes! The new laws now allow for up to two ADUs per property. A few of our customers are adding a JADU (Junior ADU) and an ADU to their properties.

How much will I have to pay in fees to the city?

if your new unit is under 750 sq ft, Nothing! Property fees vary depending on the city for ADUs over 750 sq ft. Contact us for more information.

How long will getting a building permit take?

Only up to 60 days! The building department is now required to approve ADU requests within 60 days.

Are these prefabricated homes?

No, these are not prefabricated homes. We combine off-site manufacturing with onsite assembly to overcome the limitations and inflexibility of prefab units. Our approach to home building consists of off-site robotic fabrication of the frame, and on site assembly. This allows us to offer highly personalized designs and exceptional environmental performance.

Will this effect my property taxes?

ADUs do not trigger an overall Home Property Tax Reassessment, you'll only see a slight increase based on the value the ADU brings to your property.

How big can my unit be?

Your ADU can be up to 1200 sq ft, depending on the size of your lot. Contact us for an ADU feasibility report and we will provide you with more information.

What if I don't live on the property?

No matter, the new laws do not have owner occupancy requirements.

Will I need to provide additional parking for the unit?

No, you can now replace your garage and not have to provide parking if your property is within 0.5 miles of public transit.

Does the unit have to be detached?
Not at all, depending on your needs, the unit can either be attached to your home or stand-alone.

Do you bring it over in sections or will you need a crane etc to install? 

We premanufacture the frame and structural components off-site, deliver them in sections and assemble them on site, silently, swiftly, and without cranes. Our approach allows us to avoid the logistical and costly craning process and deliver better unit layouts (that otherwise wouldn't fit in conventional trucks).



ADU 400


ADU 600


ADU 800


ADU 1000

We give shape to joyful homes.

Everyone has a story. What’s yours?

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