About the Interior Design Professional Exam (IDPX)
By: PPI
October 1, 2020

Making the decision to become a certified interior design professional by the National Council for Interior Design Qualification(NCIDQ) is a big step. Learn about the second section of the NCIDQ, the IDPX (Interior Design Professional) exam.
IDPX Exam Format and Length
The Interior Design Professional Exam division of the NCIDQ Exam is four hours long with 175 questions.
One hundred fifty of these interior design fundamentals questions are scored and the remaining 25 are used for developmental purposes and not scored.
IDPX Exam Test-Taking Tips
We recommend reviewing our interior design study books, as well as using the following tips for taking the NCIDQ IDPX:
- Try to complete each question in no more than 1 minute 15 seconds to leave a reserve of about 20 minutes to guess at unanswered questions at the end of the exam session.
- Eliminate any obviously incorrect options before attempting to guess. The chances are better between two choices than among four.
- Look for an exception to a rule or a special circumstance that makes the obvious, easy response incorrect. Although there may be a few easy and obvious questions, it’s more likely that a simple question has a level of complexity that is not immediately obvious.
- Take note of absolute words such as “always,” “never,” or “completely.” These words often indicate some minor exception that can turn what reads like a true statement into a false statement, or vice versa.
- Watch for words like “seldom,” “usually,” “best,” or “most reasonable.” These words generally indicate that some judgment will be involved in answering the question, so look for two or more options that may be very similar.
- If a question appears to be fundamentally flawed, make the best choice possible under the circumstances. Flawed questions do not appear often on the exam, but when they do, they are usually discovered by the council in the grading process. These questions will not negatively impact your score.
IDPX Content Areas
Project Coordination (15 questions, 10%)
For example:
- Critical path (e.g., design milestones, sequencing)
- Project team dynamics
- Project budgeting/tracking during design phases
- Architects
- Engineers (e.g., electrical, structural, mechanical, civil)
- Specialty consultants (e.g., landscape, lighting A/V, acoustical, food service, graphics/ signage)
- Contractors/construction managers
Real estate professionals (e.g., realtor, landlord, leasing agent, developer, property owner)
Codes and Standards (27 questions, 18%)
For example:
- Universal/accessible design
- Life safety (e.g., egress, fire separation)
- Zoning and building use
- Environmental regulations (e.g., indoor air quality, energy conservation, renewable resources, water conservation)
- Square footage standards (e.g., code, BOMA, lease)
Building Systems and Integration (24 questions, 16%)
For example:
- Building construction types (e.g., wood, steel, concrete)
- Building components (e.g., doors, windows, wall assemblies)
- Mechanical systems
- Electrical systems
- Lighting systems (e.g., zoning, sensors, daylighting)
- Plumbing systems
- Structural systems
- Fire protection systems
- Low voltage systems (e.g., data and communication, security, A/V)
- Acoustical systems
- Sequencing of work (e.g., plumbing before drywall)
- Permit requirements
Product and Material Coordination (21 questions, 14%)
For example:
- Cost estimating
- Product components (e.g., types, assembly, methods)
- Material detail drawings (e.g., custom products)
- Lead time (e.g., manufacturing time, delivery)
- Installation
- Life safety (e.g., flammability, toxicity, slip resistance)
- Technical specifications
- Maintenance documents (e.g., warranties, manuals)
- Existing FF&E inventory documentation
- Procurement procedures (e.g., purchase orders, prepayment requirements)
Contract Documents (24 questions, 16%)
For example:
- Cover sheet (e.g., General Conditions and Notes, drawing index)
- Code required plans (e.g., egress, accessibility, specialty codes)
- Elevations, sections and details (e.g., partition types, millwork)
- Consultant drawings (e.g., MEP, structural, security, specialty consultants)
- Specification types (e.g., prescriptive, performance, and proprietary)
- Specification formats (e.g., divisions)
Contract Administration (27 questions, 18%)
For example:
- Project management (e.g., schedule, budget, quality control)
- Forms (e.g., transmittals, change orders, bid/tender, addenda, bulletin, purchase orders)
- Punch list/deficiency lists
- Site visits and field reports
- Project meetings/meeting management/meeting protocol and minutes
- Shop drawings and submittals
- Construction mock-ups
- Value engineering
- Project accounting (e.g., payment schedules, invoices)
- Contractor pay applications
- Project close-out
- Post-occupancy evaluation
Professional and Business Practices (12 questions, 8%)
For example:
- Scope of practice
- Proposals (e.g., time and fee estimation, RFP process, project scope)
- Budgeting principles and practices (project specific)
- Contracts
- Phases of a project
- Business licenses (e.g., sales and use tax, resale certificates)
- Accounting principles (office/business)
- Legal considerations (e.g., liabilities and forms of business)
- Insurance
- Professional licensure, certification, registration
- Economic factors
Ready to ace the NCIDQ exam?
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