NCIDQ IDPX key terms

The research phase in which the designer gathers and documents client needs, goals, budget, and space requirements before any design work begins. Its output is a written program that scopes the project.

A grid that rates how closely each pair of spaces should be located, using symbols or numbers. Designers use it to test bubble diagrams and stacking options against functional relationships before committing to a plan.

A loose, non-scaled drawing of circles or blobs representing rooms and lines showing desired connections. It explores zoning and relationships early, before walls, dimensions, or code constraints are fixed.

A scaled diagram showing each space as a simple rectangle at correct size and location. It tests whether the programmed areas actually fit the building shell before detailed design begins.

The usable floor area of spaces that serve the occupant directly, such as offices, workstations, and conference rooms. It excludes walls, corridors, mechanical rooms, and other support space.

The total floor area measured to the outside face of exterior walls, including corridors, mechanical rooms, and structure. It is used for cost estimating, code occupancy calculations, and building comparisons.

Net assignable area divided by gross area, expressed as a percentage. It tells how much of a building actually serves occupants; low ratios signal generous circulation or heavy core and mechanical space.

The floor area used to calculate a tenant's rent, typically including a share of common corridors, restrooms, and lobby space. Leasing standards such as BOMA define how it is measured and allocated.

The centralized zone containing elevators, stairs, restrooms, shafts, and mechanical rooms. Its size and position drive efficiency, travel distances, and structural bay planning on each floor.

The paths people use to move through a space, including corridors, aisles, stairs, and entries. Good circulation separates public, private, and service routes and keeps travel direct and legible.

Designing environments usable by the widest range of people without adaptation, addressing reach, clearance, vision, hearing, and cognition. It goes beyond minimum accessibility codes to support aging, injury, and varied ability.

A continuous, unobstructed path connecting entries, rooms, and amenities that meets minimum width, slope, and surface requirements. It must remain usable in the same location as the general circulation path.

The unobstructed ground area needed for a wheelchair or scooter to approach and use a fixture, control, or element. Codes specify its size and position for forward and side approaches.

The diameter of the circle a wheelchair needs to reverse direction or turn around, commonly 60 inches for a full turn. It sets minimum sizes for restrooms, vestibules, and tight work areas.

The number of people a space is calculated to hold, based on floor area divided by a code occupancy factor for that use. It drives egress width, exit count, and plumbing fixture counts.

The continuous, unobstructed means of escape from a building to a public way, including exit access, exits, and exit discharge. Codes govern its width, number of exits, and protection.

The measured length of the path from the most remote point in a space to the nearest exit. Codes cap it by occupancy type and whether the building is sprinklered.

The portion of the egress path that leads from any occupied point to an exit, such as a corridor or aisle. It is distinct from the exit itself, which is protected from fire and smoke.

The fire-rated walls, doors, and construction that protect an exit stairway or passage from smoke and fire. It keeps the escape route tenable while occupants evacuate.

Construction that resists fire spread for a rated period, such as a one-hour or two-hour wall assembly. Ratings are assigned by building code based on occupancy, height, and area.

Dividing a building into fire-rated zones with rated walls, floors, and doors to limit fire and smoke spread. It buys time for evacuation and protects property and critical functions.

The time in hours or minutes that a material or assembly resists fire under standardized testing, such as ASTM E119. Ratings appear in code tables and govern walls, doors, and structure.

A rating of how quickly flame travels across a material's surface during a standard test, reported as a flame spread index. Codes limit it for finishes in corridors and exits.

A rating of how much smoke a material produces when burned in a standard test. Codes limit it, along with flame spread, for interior finishes in exits and corridors.

A continuous membrane of rated construction that resists smoke passage, used to separate smoke compartments. Unlike a full fire wall, it addresses smoke movement more than structural fire endurance.

The exposed surface material of walls, ceilings, and floors, such as paint, paneling, or carpet. Its class rating for flame spread and smoke limits where each finish may be used.

Required lighting along the escape path so occupants can find their way out during normal and emergency conditions. It is backed by exit signs and battery or generator power.

An illuminated or photoluminescent sign marking the direction of travel to an exit. Codes specify its visibility, lettering, and power source so it remains legible during an outage.

The phase after programming in which the designer tests concepts, layouts, and massing against the program. Deliverables include plans, sections, elevations, and preliminary budgets for client approval.

The phase that refines an approved schematic into coordinated drawings and specifications, fixing materials, systems, and dimensions. It ends with a set complete enough to begin construction documents.

The final drawings and specifications that define the work for bidding and construction. They must be coordinated, code-compliant, and detailed enough to build from and administer the contract.

Written requirements describing materials, products, workmanship, and quality standards for the project. Specs complement drawings and are organized by standard divisions such as CSI MasterFormat.

A contractor's product data, shop drawing, or sample submitted for the designer's review before installation. Review confirms the item meets the design intent but does not relieve the contractor of responsibility.

A list of incomplete or defective items identified during a final walkthrough near substantial completion. The contractor must correct them before final payment and closeout.

The stage when the work is sufficiently complete for the owner to occupy and use it for its intended purpose. It starts warranty periods and shifts certain risks to the owner.

A structured review after occupants have used a space for a while, measuring performance against the original program and goals. Findings inform future projects and can justify adjustments to the current one.

A written record of the assumptions, codes, standards, and performance goals behind the design. It documents what the design must achieve and supports later verification and commissioning.

A quality process that verifies building systems are installed, function, and perform as the owner intended. It spans design review, testing, and training, and produces documented confirmation.