OBC Large Buildings key terms

The statute that establishes the legal framework for building regulation, including permit issuance, inspector powers, enforcement, and the authority to adopt the building code itself.

Written municipal authorization required before constructing, altering, demolishing, or changing the use of a building, issued only after plans and documents satisfy code requirements.

The appointed official responsible for administering and enforcing building regulations within a jurisdiction, including issuing permits, directing inspections, and ordering compliance or remedial action.

A written enforcement notice issued when work contravenes the code or proceeds without a permit, directing the owner or constructor to stop, correct, or legalize the non-compliant condition.

An enforcement instrument halting construction activity that is unauthorized or unsafe, remaining in force until the cited deficiencies are resolved and the authority permits resumption.

A licensed architect or professional engineer who signs and seals design documents, taking legal responsibility for the portions of work within their professional scope and competence.

Documented periodic site observation by the registered design professional during construction to confirm that work substantially conforms to the sealed design and to report identified deviations.

Authorization allowing a completed building or portion to be used for its intended occupancy, granted after inspections confirm compliance with life safety and accessibility requirements.

A design, material, or system that differs from the acceptable solutions in the code but achieves the required level of performance through demonstrated equivalency accepted by the authority.

A design approach that satisfies stated objectives and functional statements through engineering analysis rather than prescriptive rules, often using fire modeling and probabilistic assessment.

The stated goals and the broad functional requirements in the code that acceptable solutions are presumed to satisfy, used to judge whether an alternative solution is equivalent.

A demonstration that an alternative design provides a level of safety and performance at least equal to that expected from compliance with the applicable acceptable solutions.

The categorization of a building or space by its intended use, such as assembly, business, residential, mercantile, industrial, or storage, which determines applicable safety and construction rules.

A principal use classification assigned to a building or fire compartment that governs allowable height, area, construction type, and fire protection requirements for that space.

A building containing two or more major occupancies, requiring fire separations, ratings, or compartmentation to limit hazard transfer between differing uses.

The measured floor area of a building used to test compliance with size limits, calculated per prescribed rules that account for exposed building face and street proximity.

The vertical dimension measured from grade to a defined reference plane, used to limit building size according to construction type and fire protection features.

A classification describing the combustibility and fire-resistance of structural elements, ranging from noncombustible protected assemblies to heavy timber or combustible framing.

A permitted enlargement of the base building area granted for features such as frontage on streets, sprinkler protection, or open space around the building perimeter.

A space enclosed by fire separations or firewalls with a required resistance rating, intended to confine fire and smoke and limit spread to other parts of a building.

A construction assembly that resists the passage of fire for a stated period, used to divide spaces, separate occupancies, or protect exits and hazardous areas.

The time in hours or minutes that a building element, assembly, or separation withstands a standardized fire exposure test without failing its assigned criteria.

A continuous and unobstructed path of travel from any point in a building to a public way, comprising exit access, the exit itself, and exit discharge.

The measured length of the path an occupant follows from a point in a floor area to the nearest exit, limited according to occupancy and fire protection features.

The clear capacity dimension of exit stairs, corridors, and doorways, calculated from occupant load to ensure rapid evacuation without crowding or blockage.

The computed number of persons a space or floor is designed to hold, derived from floor area and use factors, and used to size exits and life safety features.

The design quality enabling persons with disabilities to approach, enter, use, and exit a building and its facilities independently, achieved through prescribed dimensional and feature requirements.

A continuous route through a building that is free of steps and obstructions, with adequate width, slope, and surface conditions for independent wheelchair travel.

A toilet room designed with required clear floor space, grab bars, fixture heights, and turning radius so that a person using a mobility device can maneuver and use fixtures.

A force or demand imposed on structural elements, including dead, live, snow, wind, earthquake, and thermal effects, used as the basis for design calculations.

A design method verifying that a structure resists factored loads without collapse and performs acceptably under service conditions, using specified load and resistance factors.

A prescribed arrangement of factored or unfactored loads applied simultaneously in design, reflecting the probability that different load effects occur together.

The environmental separator comprising walls, roofs, windows, and foundations that controls heat, air, and moisture transfer between interior and exterior conditions.

A continuous assembly of materials resisting uncontrolled air leakage through the envelope, preventing energy loss, condensation, and moisture damage within assemblies.

A material layer restricting diffusion of water vapour into building assemblies, positioned to prevent condensation within walls, roofs, and floors.

The measure of an assembly's resistance to heat flow, expressed as an R-value, used to set minimum insulation performance for envelope components in each climate zone.

Demonstration that a building meets prescribed energy performance requirements, either through prescriptive envelope and equipment rules or through whole-building performance modeling.

The required number and type of sanitary fixtures determined from occupant load and use, ensuring adequate facilities for the building's occupants.

A document describing emergency procedures, occupant responsibilities, inspection schedules, and system maintenance for a building, required for certain occupancies and alternative solutions.

An automatic fire suppression network of piping and heads that discharges water on detection of heat, often permitting reductions in other fire protection or size requirements.

The examination of submitted drawings and supporting documents by the authority to verify compliance with code requirements before a permit is issued.

A signed statement by a registered design professional confirming that the design described in permit documents complies with the code and applicable standards.