Read first. Decide later.
Guides, a checklist and a project brief you can use on your own. None of them asks for your contact details.
Guides
ADU types explained
Which kind of ADU could work on my property?
An accessory dwelling unit (ADU) is a second, complete home on the same lot as a house. There are three common ways to create one, and a smaller fourth option inside the house. They differ mostly in what already exists on your property.
Related service: ADUsRemodeling while you live at home
Can we stay in the house while it is remodeled?
Often, yes, but the answer depends on which rooms are involved and when. Planning the sequence of work around daily life matters as much as the design.
Related service: Remodeling & additionsBuilding on a vacant lot
What should I check before buying or designing on an empty lot?
An empty lot looks simple, but most of the early unknowns are underground or on paper. Checking them first avoids designing a home the lot cannot support.
Related service: New homes
Plan on your own
Project brief
Three short questions, then a summary you can print or save as a PDF.
Compare routes
Remodel, addition and attached ADU, side by side.
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Start prepared
A checklist you can use on your own. Nothing here asks for your contact details.
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All questions
Every short answer on the site, grouped by topic.
Zoning and setbacks, whether utilities reach the lot, soil and slope, and access for construction. A site review before you commit is worth more than any early design.
It looks at the lot before anything is designed: zoning and setbacks, where utilities are, soil and slope, access for construction, and anything recorded on the property. The result is a short list of conditions to confirm with the city and any specialists.
It depends on the condition of the existing house, what the city allows, and what you need. Comparing both for the same property is the only honest way to decide.
An addition enlarges your existing home and stays part of one dwelling. An attached ADU is a separate unit with its own entrance, kitchen and bathroom, reviewed under ADU rules.
Often yes, with planning around noise, dust, utilities and access. Some stages, such as work on kitchens or main systems, may make it harder.
Work that changes the structure, plumbing, electrical or mechanical systems usually does; purely cosmetic work often does not. Your city decides, so confirm before work starts.
Through a new foundation beside the house, framing that ties into the existing walls and roof, and weatherproofing where old meets new. How the roofs meet and whether the floor levels match are decided early in design.
Yard space, setbacks, existing structures and utility routes usually narrow it down. A garage conversion reuses a structure; a detached unit needs yard space; an attached unit shares a wall with the house.
For an ADU on a single-family lot, state law says the city may not add an owner-occupancy requirement, but it may require rentals to be for terms of 30 days or longer (California Government Code §66315). Junior ADUs have their own rules, and other local requirements still apply, so confirm with your city before deciding.
A junior ADU is no larger than 500 square feet and is contained entirely within a single-family home. It may have its own bathroom or share one with the house (California Government Code §66313).
State law says a city may not require the lost off-street parking to be replaced when a garage is converted to an ADU (California Government Code §66314(d)(11)). Your city’s other requirements still apply, so confirm them before you plan.
Not exactly from a web page. For remodels, additions and ADUs, the cost calculator on the homepage shows an early planning range based on published California builder pricing; it is not a quote. Cost depends on the site, the size, the design and finishes, so a realistic number for your project comes after the property has been reviewed and a concept exists.
Size, site conditions, how much of an existing structure changes, and finish level. The scope section on each service page explains each one.
Yes. Plans are reviewed and approved by the city before physical work begins, and inspections happen at stages during construction.
You talk through your goals, the property and your questions. Bringing the preparation checklist from the Resources page makes it more useful.
