THE SERVICE
Expand Your Bay Area Home with a Custom Addition or ADU
Whether you’re expanding your living space, adding a new bedroom, or building a detached ADU for guests or rental income, Artemis Building Co. delivers expert design-build services that seamlessly integrate with your home and meet California’s building standards. We make the process smooth, efficient, and built to last.
Creativity
From creative space planning to maximizing natural light and privacy, we design additions and ADUs that feel like they’ve always belonged.
Craftsmanship
Our team builds with precision and integrity — using quality materials, experienced trades, and a strong commitment to getting every detail right.
Communication
We guide you through every step — from permitting to punch list — with clarity, responsiveness, and transparency.
WHAT WE DO FOR YOUR HOME
Home Addition & ADU Services
Room & Second-Story Additions
Add more space and value to your home with expertly built bedrooms, family rooms, or full second stories — all tailored to your lifestyle.
Garage Conversions
We convert existing garages into beautiful, functional living spaces, complete with plumbing, electrical, insulation, and finishes.
Detached ADUs
We design and build stand-alone accessory dwelling units (ADUs) ideal for guests, renters, home offices, or multigenerational living.
Attached ADUs & In-Law Suites
Create self-contained living spaces within your home that provide comfort and privacy — all while maintaining a cohesive design.
Permitting & Code Compliance
We handle all permitting, planning, and code compliance so your project runs smoothly and meets all local and state requirements.
Service Areas
Frequently Asked Questions
What’s the difference between a home addition and an ADU?
How much does it cost to build an ADU or home addition?
Costs vary based on size, design, and existing site conditions. Most ADUs start around $150,000, while home additions typically range from $75,000 to $250,000+. We’ll provide a detailed estimate after your consultation.
How long does the construction process take?
Timelines vary by scope, but most additions and ADUs take 3–6 months from permit approval to final walkthrough. We give you a clear project schedule before we begin.
Do I need permits for an ADU or addition?
Yes — permits are required for both. We handle all the permitting, zoning checks, and coordination with your local city or county.
Can I build an ADU on my property in the Bay Area?
Most single-family lots in the Bay Area are eligible for ADUs under California law. We’ll assess your property, zoning, and lot size during the initial consultation to confirm what’s possible.
Will the new space match the style of my existing home?
Absolutely. We design additions and ADUs to seamlessly blend with your existing architecture, materials, and finishes.
Can you help with architectural plans and design?
Yes. We partner with experienced architects and designers to create build-ready plans that reflect your goals and budget.
