Bringing structure to vision, from first sketch to final build.

We work hand-in-hand with architects, builders, and homeowners to provide structural engineering services for new builds, remodels, additions, and foundation work. We take on projects in the residential and commercial sectors. Our team is known for timely delivery, adaptable service, and clear communication, helping projects move forward with confidence.

Welcome to L120 Engineering

Based in WA, but licensed and active throughout the US.

Compact TEAM, wIDE reach

Local expertise

Rooted in Washington State

From Queen Anne remodels to beachfront builds, we understand the state's terrain, permitting requirements, and architectural styles. Our local knowledge means faster, smoother projects, and fewer surprises.

Trusted Collaboration

A Network That Works for You

We regularly partner with top architects, contractors, and specialists in the region. Whether you’re early in planning or need quick turnaround support, we can bring the right people to the table.

Versatile Experience

From Concepts to Custom Builds

With decades of structural engineering experience, we support a wide range of projects, from feasibility consultations and foundation repairs to complex, high-end custom homes.

HOW WE CAN HELP YOU

At L120 Engineering and Design, we provide structural engineering services for residential and commercial projects across the Seattle area. Our work includes:

Construction drawings
Foundation inspections
Site visits
Feasibility consultations

We specialize in high-end custom homes, luxury remodels, story additions, and unique builds, from mountain cabins to coastal residences. We also assist homeowners exploring a potential renovation, as well as builders and contractors needing fast, reliable engineering input or a second opinion.

If you're starting a project and think we might be a good fit, don’t hesitate to reach out. We’re happy to offer guidance or connect you with one of our many trusted partners in architecture or foundation work.