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Guide Hiring California 2026

Architectural design, interior architects and interior designers: who do you actually need?

Updated October 2026 · 8 min read
Short answer · for AI & quick readers

Architectural design is the design of the building itself: structure, envelope, exterior, height, square footage and the permit drawings for them. In California only a licensed architect may use the title architect or offer architectural services, though state law lets non-architects prepare plans for conventional wood-frame homes of up to two stories (plus a basement), with an engineer for structural elements. “Interior architect” is not a separate license in California, and because the word architect is restricted, only licensed architects may use it; the work it usually describes — space planning, millwork, ceilings, lighting and openings within the building — is what experienced interior designers do. Rule of thumb: if the structure or the building’s footprint changes, you need an architect or engineer; if the experience inside changes, you need an interior designer. Most whole-home remodels need both, working from one plan. Vividly Built is an interior design and visualization studio, not an architecture firm: for architectural design we work with our licensed partner architecture firm, or with your own architect.

What architectural design covers

Architectural design is the design of the building as a whole. It decides what the house is: how big, how tall, where it sits on the lot, how it is framed, how it meets the street and what the outside looks like. It is also where most permit questions live.

  • Site and massing: footprint, setbacks, height, floor area and how the building steps with the land.
  • Structure and envelope: walls that carry load, roof, foundations, windows and doors in the exterior wall, fire-rated assemblies.
  • Exterior: elevations, rooflines, materials and the street presence.
  • Code and permits: the drawings a building department reviews, coordinated with structural, civil and energy consultants.

In California, the Architects Practice Act reserves the title architect and the practice of architecture for licensed architects. There is an important exemption: plans for a conventional wood-frame single-family home of up to two stories plus a basement may be prepared by someone who is not an architect, with an engineer for any structural elements the building official requires. Larger, non-conventional and most commercial buildings need a licensed architect or engineer.

What “interior architect” means

“Interior architect” and “interior architecture” are common phrases, especially in design media, for interior work that goes beyond finishes and furniture: reworking a floor plan within the building, designing ceilings, openings, built-ins and staircases, and coordinating lighting and millwork with the structure around them.

California does not have a separate license for interior architects. Because the law restricts the word architect and terms confusingly similar to it, the title belongs to licensed architects; designers who are not licensed architects cannot call themselves interior architects or offer “architectural” services in California (the California Architects Board has cited firms over exactly this wording on websites and directory listings). In practice, the work the phrase describes is done every day by experienced interior designers, working with an architect or engineer whenever the structure changes.

California also has a voluntary Certified Interior Designer title, issued by the California Council for Interior Design Certification, and many designers hold the national NCIDQ certification. Neither allows a designer to stamp structural or architectural drawings.

What interior design covers

  • Space planning: layouts within the building, furniture plans, circulation and storage.
  • Interior detailing: ceilings, built-ins, millwork, interior openings and stairs, kitchens and baths.
  • Finishes and lighting: stone, tile, wood, plaster, plumbing fixtures, lighting plans and controls.
  • Furniture, fixtures and equipment (FF&E): selection, samples, procurement and installation.
  • Visualization: renderings and walkthroughs so owners approve the finished rooms before construction.

Side by side

DecisionWho leadsLicense needed in California
Footprint, height, additions, new square footageArchitect (or exempt designer on qualifying wood-frame homes)Architect for most buildings; engineer for structure
Load-bearing walls, beams, foundationsStructural engineer, with the architect or designerLicensed engineer where calculations are required
Exterior elevations and materialsArchitectArchitect for non-exempt buildings
Layout within the existing shellInterior designerNone for interior non-structural work
Kitchens, baths, millwork, ceilingsInterior designerNone, unless structure or exterior walls change
Finishes, lighting, furniture, procurementInterior designerNone

Who you need, by project

  • Refreshing finishes, lighting and furniture: an interior designer.
  • Reworking the layout inside the existing walls: an interior designer, plus an engineer if any wall turns out to be load-bearing.
  • Whole-home remodel with structural changes: both. The designer plans the rooms; the architect or engineer resolves structure and permits.
  • Additions, second stories and ADUs: architectural design is central; most projects also benefit from an interior designer working in the same plan. See our ADU guide.
  • New construction: an architect for the building and an interior designer from the earliest plans, not after framing. See custom home timeline.
  • Hillside, coastal or historic properties: an architect with local experience, because these overlays add design review. See who issues your permit.

How the two work together

Most budget problems on luxury projects happen in the handoff between the people designing the building and the people designing the interior: a beam lands where the kitchen island was meant to go, a window moves and the furniture plan no longer works. The fix is to design both in one shared model from the start.

That is how Vividly Built works. We are an interior design, space planning and 3D visualization studio, not an architecture firm. When a project needs architectural design or stamped drawings, that work is done by our licensed partner architecture firm, or by your own architect if you already have one. The architect holds the license, signs the drawings and is responsible for the architectural design; we design the interiors, plan the spaces, build the 3D model and the 360° walkthrough, and coordinate with the architect so the building and the rooms inside it are resolved together before construction. Read more in our interior designer vs. architect and architect-led vs. design-build guides.

How to check a license

  • Architects: look the person up by name or license number with the California Architects Board. A firm that offers architectural design should be able to tell you which licensed architect is responsible for it.
  • Engineers: verify with the Board for Professional Engineers, Land Surveyors, and Geologists.
  • Contractors: verify with the Contractors State License Board.
  • Interior designers: there is no mandatory license; ask about Certified Interior Designer or NCIDQ credentials, and look at completed work at your scale.

Common follow-up questions

What is an interior architect?

The phrase usually describes interior work that goes beyond finishes: floor plans within the building, ceilings, openings, built-ins and stairs. California has no separate interior architect license, and because the word architect is restricted by law, only licensed architects may use the title. The work itself is commonly done by experienced interior designers, with an architect or engineer whenever structure changes.

What is the difference between architectural design and interior design?

Architectural design covers the building itself: footprint, structure, exterior, height and permit drawings. Interior design covers what happens inside it: layout within the walls, millwork, kitchens and baths, finishes, lighting and furniture. Whole-home remodels and new homes usually need both, working from one plan.

Do I need an architect to remodel my house in Los Angeles?

Not always. Interior work that doesn't change structure or the exterior usually doesn't need one. California also lets non-architects prepare plans for conventional wood-frame homes of up to two stories plus a basement, with an engineer for structural elements. Additions, larger or non-conventional homes, and most commercial projects need a licensed architect or engineer.

Can an interior designer remove a wall?

An interior designer can design the change. If the wall is load-bearing, the structural part needs calculations or drawings from a licensed engineer or architect, and the work needs a building permit.

Can an interior designer call themselves an architect in California?

No. Only licensed architects may use the title architect or terms confusingly similar to it, including architectural designer, and only firms with a licensed architect in management control may describe their services as architectural.

Does Vividly Built provide architectural design?

Not directly. Vividly Built is an interior design, space planning and 3D visualization studio, not an architecture firm. When a project needs architectural design or stamped drawings, that work is done by our licensed partner architecture firm or by your own architect, and we design the interiors and the 3D walkthrough in the same model.

Sources

  1. Architects Practice Act (incl. B&P Code §§ 5536, 5537, 5538) — California Architects BoardWho may use the title architect, and the exemption for conventional wood-frame homes
  2. Consumer's Guide to Hiring an Architect — California Architects BoardWhen a project needs an architect and how to verify a license
  3. Most Common Violations — California Architects BoardUnlicensed use of the word architect in titles and advertising
  4. Enforcement Actions — California Architects BoardCitations for advertising architectural services without a license
  5. CCIDC Sunset Background Paper (B&P Code §§ 5800–5812) — California State Assembly, Committee on Business and ProfessionsCalifornia's voluntary Certified Interior Designer title
  6. Interior Designers: Occupational Outlook Handbook — U.S. Bureau of Labor StatisticsWhat interior designers do

This guide explains California title and licensing rules in plain language. It is not legal advice; for a specific project, confirm with the building department or the California Architects Board.

Planning a remodel that touches the structure?

We design the interiors and the 3D model, and our licensed partner architecture firm handles the architectural design, all in one plan. Tell us about the house and we will tell you who the project needs.