Home Additions & Renovations

Code-compliant residential expansion and renovation design focused on structural integration, feasibility, and seamless alignment with existing building systems.

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Home additions and renovations at Lumignus are treated as structural and regulatory reconfigurations rather than simple design upgrades. Every modification to an existing building introduces new constraints related to structure, zoning, building code, and permitting requirements.

In California, even minor residential changes can trigger complex regulatory review depending on scope, location, and structural impact. This makes early feasibility analysis essential to determine what can be built, modified, or expanded within existing legal and physical conditions.

Our process begins with a detailed evaluation of the existing structure, site conditions, and jurisdictional constraints. This allows us to define realistic expansion opportunities while avoiding design directions that would fail during permitting or construction.

We integrate architecture, structural engineering, and permitting strategy into a single workflow to ensure that additions and renovations are fully coordinated with existing systems. This includes structural load verification, code compliance review, MEP integration where necessary, and alignment with California energy and safety standards.

Whether expanding a single-family residence, reconfiguring interior layouts, or adding new functional space, our focus is on delivering solutions that feel seamless, structurally sound, and fully compliant with local requirements.

Our services are ideal for:

Private Homeowners in California
You own a lot and dream of a custom home, backyard ADU, or a thoughtful renovation. We’ll help you navigate zoning, design a buildable solution, and get permits—without surprises.
Real Estate Investors
You need projects that are fast to approve, compliant, and deliver strong ROI. We validate feasibility first, so your capital goes into construction—not redesigns.
Small & Mid-Sized Developers
From SB-9 duplexes to ADU portfolios and small multifamily builds, we provide end-to-end technical support—ensuring your projects are bankable, code-compliant, and on schedule.
Commercial Property Owners
Upgrading an office, retail space, or hospitality venue? Our integrated team minimizes downtime, meets strict CA codes, and enhances your asset’s value—seamlessly.
Architecture & Design Firms
You focus on vision—we handle the technical backbone. From structural coordination and BIM modeling to permitting and Title 24 compliance, we’re your reliable engineering partner.
Out-of-State Property Owners
Managing California permitting remotely introduces unnecessary complexity and risk. Lumignus acts as your local representative, coordinating directly with jurisdictions, consultants, and reviewers on your behalf throughout the entire approval process.
Have a property or idea? Let’s see what’s possible.
Whether it’s a hillside lot, an ADU, a renovation, or a commercial space — we’ll help you understand what’s buildable, what it takes, and how to move forward with confidence.
Start Your Project

Existing Structures as Active Constraints

At Lumignus, renovations and additions are understood as interventions within an existing system rather than isolated design exercises.

Every project must respond to:

  • existing structural conditions and load capacity
  • zoning limitations and setback requirements
  • California building code compliance
  • seismic and safety considerations
  • MEP system integration and capacity
  • construction feasibility within occupied or constrained sites

By addressing these conditions early, we reduce uncertainty and ensure that design decisions are grounded in real constraints rather than assumptions.

This approach minimizes redesign cycles and improves the reliability of permitting outcomes.

Integrated Renovation Approach

Our home addition and renovation services operate within a coordinated workflow that includes architecture, structural engineering, MEP systems, civil coordination where needed, and permitting administration.

This allows existing structures to be evaluated and modified as part of a unified design system rather than treated as isolated architectural problems.

Instead of separating design intent from technical feasibility, we continuously align both throughout the entire process.

The result is a more predictable, controlled, and constructible path from concept to approval and construction.

Our Core Principles

Safety

Every project is designed with structural integrity, seismic resilience, and life safety as top priorities. By integrating architecture and engineering from day one, we ensure not just a beautiful building—but a safe one for everyone who lives, works, or visits.

High Standards

Even on complex sites—steep slopes, tight zoning, or high-risk areas—we maintain full control over technical and regulatory details. The result? Fully permitted, code-compliant, and constructible designs that meet the highest professional standards.

End-to-End Support

We’re with you from initial feasibility through final construction. Need a zoning check on a weekend? A quick BIM coordination review? We’re available when it matters—because your timeline doesn’t stop at 5 p.m.

Trusted Provider

Lumignus has delivered hundreds of buildable projects across California—from hillside homes to commercial retrofits. Every client receives a risk-aware, financially sound solution. We guarantee technical accuracy, transparency, and on-time delivery—every time.

Licensed & Verified Professionals

All work is led and reviewed by licensed architects and engineers. As required by California law, architectural and engineering services are coordinated exclusively through appropriately licensed experts. This ensures legal compliance, smooth permitting, and zero surprises during construction.

Our Clients

Case Study

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Reviews

28.06.2026

We worked with Lumignus on two projects—an ADU conversion and a one-bedroom addition with a full remodel of our main house. Ilia, Sasha, and Kevin were great to work with throughout the process.Despite tight deadlines and challenging winter weather, both projects were completed on time and within budget. Communication was clear, the quality of work was excellent, and we are very happy with the results. We highly recommend Lumignus for any construction or remodeling project.

Rajolu Venukumari
24.06.2026

I had a fantastic experience working with Ilia and Kevin. We hired their company for a kitchen remodel, ADU construction, and landscaping project, and the results exceeded our expectations. Everything turned out even better than we imagined. The pricing was fair, communication was great, and the entire process was smooth and stress-free. We are very happy with the final outcome.

John Martinez
15.06.2026

We bought a 3-bedroom house from the 1960s that was in very poor condition. Lumignus first prepared a feasibility study and then helped us transform the property by adding a second floor with 2 bedrooms and 1 bathroom, plus a guest house.They handled everything from architectural, structural, and MEP plans to permits and construction. The entire process was smooth, and we are very happy with the result. Highly recommend!

Brodie Phillips
09.06.2026

We had a clear vision for what we wanted to create with our guesthouse, and from the very beginning Kevin really understood what we were looking for. Not only did he listen to our ideas, but he also brought creative suggestions and even better solutions that elevated the final result.Kevin was always responsive, straightforward about what was possible, and kept everything moving without delays. We truly appreciated the communication, professionalism, and attention throughout the process.

Scarlett Bennett
17.10.2026

I had the pleasure of working with Josh, Ilia, and Lois on the build-out of our new dermatology and laser medical office in West LA, and I couldn’t be happier with the outcome! From start to finish, their professionalism, dedication, and attention to detail were exceptional — every part of the office was built to the highest standards.They not only created a beautiful, functional space but also maintained excellent communication throughout the entire process. Thank you for an outstanding job!

Maxwell Scott
5.10.2025

Lumignus did an incredible job on my ADU. The entire process went smoothly — they clearly know their work. I had lots of questions along the way, and they patiently explained everything in detail. The final result exceeded my expectations — it looks solid, clean, and exactly the way I wanted. Highly recommend!

Muhammad Riaz
27.09.2025

If I could, I’d give Ilia 10 stars instead of 5! He did double the work at just a third of the price compared to other architects I spoke with. His team was incredibly responsive, always available to address my questions and concerns. They were just as driven as I was to get my plans approved. Thanks to Ilia, navigating the challenging process with the City of Beverly Hills became a manageable experience. Thank you!

Ken Ive
24.09.2025

I highly recommend Lumignus for their talented team of architects. We hired them to design plans for remodeling our kitchen and bathrooms, as well as creating a new master bedroom and bathroom by converting an existing space. After our initial meetings, they quickly understood our design preferences, and the 3D renderings looked fantastic. The team was professional, easy to work with, and delivered high-quality work. Their customer service was exceptional—they were very responsive and also took care of filing all the necessary permits.

Isla Warfield
24.09.2025

To start, I didn’t originally hire Lumignus—my previous contractor did. However, after firing that contractor due to various issues, I decided to continue working with Lumignus. I needed engineering support to permit previously unapproved work on a 2,300 square foot shop. The county required those permits before issuing approval for our interior remodel, which included removing a load-bearing wall, eliminating a kitchen soffit, and more. The process was complicated, and the county’s requirements were often difficult and at times seemed unreasonable. Beatrice worked closely with my new contractor, and together they managed to address all of the county’s demands. I'm very grateful for their help—thank you both.

Pamela Labreche
24.09.2025

Nadia designed 4 ADUs for me, each unique and perfect. She was incredibly prompt, handling all the clearances efficiently, saving me tons of time. Her fees were reasonable, and the final designs exceeded my expectations. Highly recommend!

Richard Henry

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