Signature Construction Services
Our core service offerings represent our highest areas of expertise and the projects we've built our reputation on.
New Construction
Building from the ground up is our specialty. We manage every phase of new residential and commercial construction — from architectural coordination and permitting through framing, systems installation, and final finishes. Our team delivers structurally sound, code-compliant builds that reflect your vision with precision.
New Additions
Need more space without moving? A well-designed room addition can dramatically expand your living or working area while increasing property value. We seamlessly integrate new additions with your existing structure — matching architectural style, roofline, and finishes for a cohesive, premium result.
Garage Conversion to Living Space
Unlock the hidden potential of your garage. We convert underutilized garage space into beautiful, fully habitable living areas — whether that's a studio apartment, home office, media room, or guest suite. Every conversion is fully permitted, insulated, and code-compliant.
ADU Specialist
California's ADU laws have made adding a second unit easier and more profitable than ever. MJ3 Builders specializes in detached ADUs, attached ADUs, and junior ADUs — all designed to maximize rental income or multigenerational living value while fully complying with state and local regulations.
