Interior Designer
The professional who plans and specifies the interior spaces of buildings.
Quick Answer
An interior designer is a professional who plans, designs, and specifies interior spaces, including layouts, finishes, lighting, and furnishings. Commercial interior designers must consider building codes, accessibility, and life safety. They produce plans, finish schedules, and details, and may be credentialed through the NCIDQ exam and state registration where required.
The Full Picture
Interior designers shape how interior spaces function and feel. They develop space plans, select finishes and materials, coordinate lighting and ceilings, and specify furniture and fixtures. On commercial projects they work with the architect or sometimes lead tenant improvement projects themselves.
Professional qualifications vary by state. Many jurisdictions regulate use of the title or the practice of interior design, and the NCIDQ examination from CIDQ is a common credential for qualified interior designers. Interior design is distinct from decoration, which focuses on furnishing and styling, and from architecture, which carries broader legal responsibility for building design.
Their deliverables include interior floor plans, reflected ceiling plans, elevations, millwork details, and finish schedules, along with specifications for finishes and furniture. These documents must align with the architect's partition types, ceiling systems, and code requirements, and with MEP coverage for lighting and diffusers.
For contractors, interior packages such as finishes, millwork, and specialty ceilings carry cost sensitivity and long lead times. Finish and furniture scope also often falls between the GC and the owner, so careful review of what is included in the contract versus owner-furnished items is part of preconstruction.
Real Examples
Common Misconceptions
People assume: Interior designers just pick colors and furniture.
Actually: Commercial interior designers handle space planning, code and accessibility requirements, technical details, and specifications, not only aesthetics.
People assume: Interior designers and interior decorators are the same.
Actually: Decorators focus on styling and furnishings and typically do not prepare construction documents. Designers often have formal education, credentials, and responsibility for technical documents.
Frequently Asked Questions
What does an interior designer do?
They plan interior layouts, select and specify finishes, lighting, and furnishings, and produce drawings and schedules, while ensuring the design meets code and accessibility requirements.
Do interior designers need a license?
It depends on the state. Some regulate the title or practice, and many qualified designers hold the NCIDQ certification. Requirements vary widely by jurisdiction.
What is the difference between an interior designer and an architect?
Architects are licensed to design buildings and are responsible for structure, systems coordination, and code compliance. Interior designers focus on interior spaces and often work within a building the architect designed.
What is a finish schedule?
A finish schedule lists the floor, wall, base, and ceiling finishes for each room. It is a key document for estimating interior finish costs.
Why do interior drawings matter to contractors?
They define finishes, millwork, and specialties that carry significant cost and lead time, and they often reveal owner-furnished versus contractor-furnished scope questions.