`ADU & Garage Conversions`

Maximize your property’s value and living space. From functional garage transformations to fully detached backyard homes, we handle everything from city permits to the final coat of paint.

Our ADU Solutions

From converting existing spaces to building brand new units, we offer solutions to fit your property and investment goals.

Garage Conversions

Transform your unused garage into a profitable rental unit or a comfortable guest suite. We handle the structural upgrades, Title 24 insulation, and new utility connections required by California code.

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Detached ADUs (Ground-Up)

Maximize your backyard’s potential with a fully independent home. As a licensed Class B contractor, we manage the entire build: from trenching and pouring the foundation to expert framing and final interior finishes.

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Navigating California ADU Laws

Building an ADU in Orange County involves strict zoning laws, setbacks, and Title 24 energy compliance. Coastline Harmony Builders, Inc. simplifies this complex process. We execute your architect’s plans with precision, ensuring your project is fully permitted, legally compliant, and built to the highest structural standards.

Ready To Expand Your Property?

From initial site evaluation to flawless construction, trust Coastline Harmony Builders to deliver a high-quality ADU that adds lasting value to your home.

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Fully Licensed, Insured & EPA Lead-Safe Certified for your peace of mind.