More home. Same address.
Whether you need a primary suite that finally feels right, a second story that makes the lot work harder, or a family room that connects the way your home never did — Onyx designs and builds additions that feel like they were always there.
The home you want is already on your lot
Most Los Angeles homeowners don't need to move — they need more room, in the right place, built in a way that makes the existing house better rather than just bigger.
The addition has to belong to the house
A home addition that looks appended — mismatched roofline, different stucco texture, awkward proportions — diminishes the whole. Onyx treats matching as a structural and aesthetic priority, not an afterthought. Every addition is designed so the seam disappears.
Zoning, permits, and structural reality come first
Los Angeles has some of the most variable zoning conditions in the country — lot coverage limits, setback requirements, height restrictions, and hillside rules all affect what's buildable. Onyx assesses feasibility before design begins, so no planning effort is wasted.
What are you adding?
Each addition type comes with its own structural considerations, permit requirements, and design opportunities. Read each one as a starting point — not a constraint.
Room Addition
A single-room addition — bedroom, home office, family room, or guest suite — is the most direct way to add what's missing without touching what already works. Built outward from the existing footprint, it works on most LA lots where setbacks and coverage allow.
Second Story Addition
When the lot doesn't allow outward expansion, building up is the answer. A second story typically adds the largest square footage relative to site impact — bedrooms, bathrooms, and a primary suite above a footprint that already exists. It requires a foundation and structural assessment before design begins.
Kitchen or Living Room Expansion
Expanding a kitchen or living area outward — even by ten to twelve feet — can transform how the home functions daily. This is often the addition that changes the most about how a family actually lives, and one of the highest-return investments in Los Angeles real estate.
Primary Suite Addition
A dedicated primary suite — with a bedroom, bathroom, walk-in closet, and wherever possible a private outdoor connection — changes the quality of daily life in a home that never had one. It's the addition most often described by homeowners as the one they wish they'd built sooner.
The hardest part isn't building it — it's matching it
Any contractor can frame a room. The challenge is making the addition read as part of the original house rather than something tacked on. That requires matching stucco finish and texture, matching roof pitch and overhang, continuing interior flooring and millwork profiles, and aligning structural and electrical systems in a way that doesn't show.
Onyx focuses on this from the first design conversation. The seam between old and new construction is where the quality of an addition contractor reveals itself — and it's where most fall short.
Homeowners in Brentwood, Hancock Park, Los Feliz, Pasadena, and Santa Monica have a particular need for this precision, where the architectural character of the neighborhood is part of what makes the home valuable.
What every addition project includes
Onyx manages the full scope — from initial feasibility through final inspection. There is no hand-off between design and construction.
Feasibility & zoning review
Lot coverage, setbacks, height limits, and structural capacity — assessed before any design work begins.
Design & plans
Architectural drawings developed in collaboration with your vision and submitted for permit approval.
Permits & inspections
All LADBS permits handled in-house, including structural, electrical, plumbing, and framing inspections.
Construction & finish
Full construction management, subcontractor coordination, and quality control through punch-list and final walk.
From first conversation to finished addition
The decisions made before construction begins determine more of the outcome than any choice made during it.
Assess what's possible on your lot
Before design, we review your zoning, setback requirements, lot coverage, existing foundation, and any neighborhood-specific restrictions that affect what can be built.
Design for how you want to live
The addition is designed around your household's actual needs — how you move through the home, what's currently missing, and what the new space needs to do — not just around square footage.
Permits and pre-construction
We submit for and obtain all required permits, finalize the material package, and coordinate subcontractors before a single wall is opened. No surprises after construction begins.
Build and deliver
The addition is built to the approved plans, matched to your existing home, inspected, and delivered with the finish quality and timeline agreed upon at the start.
Why homeowners across Los Angeles choose Onyx
Home additions are among the most structurally complex residential projects in LA. They require the same quality standard as new construction — in a home you're still living in.
LA zoning expertise
Los Angeles zoning varies block by block — R1 lots, hillside ordinances, fire zones, and historic overlay districts each carry different constraints. Onyx has built across Santa Monica, Bel Air, Silver Lake, Sherman Oaks, and Encino, and navigates these requirements without delays or redesigns.
Design-to-build continuity
The same team that designs the addition manages the construction of it. There is no gap between what was drawn and what gets built — a gap that accounts for most of the disappointments homeowners describe after working with multiple firms on a single project.
Matching as a priority
Every addition Onyx builds is designed to read as original construction. Material selection, detailing, and finish are held to the same standard as the existing home — not approximated. Homeowners in Hancock Park, Pasadena, and Mar Vista know the difference, and so do buyers.
Common questions about home additions in Los Angeles
Home additions in Los Angeles typically range from $300 to $600 per square foot depending on scope, materials, structural complexity, and neighborhood. A single-room addition is generally less complex than a full second story. Onyx provides detailed project estimates before any commitment is made.
Yes. All home additions in Los Angeles require permits through the Department of Building and Safety. Onyx handles the full permitting process — plans, applications, inspections, and approvals — as part of every project.
A single-room addition typically takes three to five months from permit approval to completion. A second story or larger expansion may take six to ten months depending on scope, structural requirements, and finish selection. Onyx provides a detailed timeline before construction begins.
In most cases, yes. The feasibility depends on your existing foundation, lot zoning, setback requirements, and current structural condition. Onyx evaluates these factors during the initial assessment and provides a clear recommendation before any design work begins.
Matching is a central priority for every Onyx addition. The design phase focuses on ensuring the addition reads as part of the original home — in material, proportion, and architectural character — rather than as something appended to it.
For most ground-floor additions, yes. The construction sequence is managed to minimize disruption to occupied areas. For full second-story additions or projects involving extensive structural work, temporary relocation may be recommended for a portion of the build.
Ready to talk about your addition?
Most projects begin with a conversation about what's missing from the home and what the lot can support. Onyx can walk you through both — before any plans are drawn or budgets are committed.