Technical Drafting and Building Code Standards: Alphabets of Lines, Scales, Elevations, and Architectural Guidelines

Vocabulary practice flashcards covering technical drafting conventions, the alphabet of lines, scaling methods, architectural elevation views, and residential building standards from Presidential Decree No. 1096 (National Building Code of the Philippines).

Alphabet of Lines

A standardized collection of line types, weights, and styles utilized in technical drafting and blueprints to convey the shape, size, and specific characteristics of a design.

Object Line

A thick or visible line used to represent the visible edges and exterior outlines of an object or building element.

Hidden Line

A dashed line type used to depict edges, surfaces, or structural features that are concealed from direct view.

Center Line

A line composed of alternating long and short dashes that indicates the center, longitudinal axis, or axis of symmetry of an object or feature.

Dimension Line

A thin line terminated with arrowheads or tick marks that indicates the exact distance or numerical measurement between two points.

Extension Line

A line extending outward from an object outline to delineate the starting and stopping limits of a dimension line.

Leader Line

An angled line with an arrowhead or dot that points directly to a feature to connect it with a explanatory note, label, or material specification.

Cutting-Plane Line

A heavy line terminating with arrows that identifies the imaginary cutting path through an object to generate a sectional view.

Section Line

Uniformly spaced parallel lines (typically angled at $45^\circ$) drawn across an exposed cut surface to indicate solid material in section views.

Break Line

A line style showing that an object has been partially broken away, cut short, or removed to fit within the drawing space.

Phantom Line

A line composed of a series of one long and two short dashes used to show alternate positions of a moving component, adjacent part relationships, or repetitive features.

Construction Line

A faint, lightweight drafting line used as a temporary layout guide and alignment reference during the initial drafting stage.

Border Line

A prominent, heavy continuous line drawn around the perimeter of a drawing sheet to establish the formal boundary of the drawing area.

Ground Line

A reference line in an architectural elevation that marks the finished ground surface level from which elevations and building heights are measured.

House Elevation

A vertical drawing showing the exterior appearance of a building from a specific viewpoint, communicating height, width, proportions, finishes, and exterior openings.

Triangular Scale

A three-sided measuring tool (architect's scale) calibrated with different ratio scales (such as $1:20$, $1:50$, $1:75$, $1:100$, $1:125$, and $1:200$) used to lay out and measure proportional dimensions on plans.

Floor Plan

A scaled orthographic diagram of a room or building viewed from directly above, displaying horizontal boundaries, walls, dimensions, doors, windows, and equipment layouts.

Presidential Decree No. 1096

The National Building Code of the Philippines, enacted on February 19, 1977, establishing national technical and legal standards for building design, construction, and occupancy.

Group A Dwelling

A residential structure category under Section 708 of the NBCP designated primarily for single-family occupancy or low-occupancy residential use.

Corner Lot Building Coverage and Open Space

A zoning standard allowing a residential building to occupy up to $90\%$ of a corner lot's total area, mandating that at least $10\%$ remain unobstructed open space.

Minimum Setback (Group A Dwellings)

A mandatory spatial clearance requiring residential structures to remain at least $2.0\,\text{m}$ away from all property boundary lines to ensure adequate yards, light, and ventilation.

Stair Dimensions (Group A Dwellings)

Mandated staircase parameters specifying a minimum clear width of $750\,\text{mm}$, a rise of $200\,\text{mm}$, and a minimum run of $200\,\text{mm}$.

Foundation Footing (Group A Dwellings)

The lower structural support of a dwelling required to be at least $250\,\text{mm}$ thick and embedded a minimum of $600\,\text{mm}$ beneath the surface of the ground.

Room for Human Habitation

A primary habitable room required under Section 806 of the NBCP to encompass a minimum floor area of $6.00\,\text{m}^2$ with a least horizontal dimension of $2.00\,\text{m}$.

Kitchen Dimension Standard (Section 806)

A room intended for food preparation, legally required to possess a floor area of at least $3.0\,\text{m}^2$ and a least horizontal dimension of $1.50\,\text{m}$.

Bath and Toilet Dimension Standard (Section 806)

A sanitary installation space requiring a minimum floor area of $1.20\,\text{m}^2$ with a least horizontal dimension of $0.90\,\text{m}$.

Mezzanine Floor Clear Height

The legal vertical headroom clearance on or beneath a mezzanine floor level, which must measure at least $1.80\,\text{m}$.

Residential Firewall

A solid masonry or brick partition wall built with a thickness of $150\text{--}200\,\text{mm}$ or more (commonly $200\,\text{mm}$) to prevent fire spread, grant acoustic privacy, and ensure structural durability between adjoining properties.

Exterior Wall Thickness (Residential CHB)

The standard construction thickness for exterior concrete hollow block (CHB) or AAC block walls, specified as $150\,\text{mm}$ ($6\text{"}$).

Interior Partition Thickness

The standard architectural wall thickness utilized for interior dividing partitions in residential structures, specified as $100\,\text{mm}$ ($4\text{"}$).

Exit Door Swing (Section 1207)

A mandatory egress requirement stating that an exit door must swing outward in the direction of exit travel.