Below is a glossary of architectural elements and terms that appear in LPC’s application instructions and on this website.
Architect: An individual, partnership, corporation or other legal entity licensed to practice the profession of architecture under the education law of the State of New York.
Architrave: 1. The lowest part of a classical entablature. 2. A molding enframing an opening such as a window or areaway or the open space between a rowhouse and the sidewalk, usually beside the stoop.
Armature: A metal structural support for a rigid projecting sign. The armature may support the bracket sign by means of one or two projecting arms.
Authorization to Proceed (ATP ): A letter from LPC notifying an applicant that certain work types, such as the installation of air conditioners or replacement windows, conform with the provisions of an approved Master Plan.
Awning: A metal frame clad with fabric attached over a window, door, porch opening or storefront to provide protection from the weather.
Baluster: One of a series of short vertical posts, often ornamental, used to support a rail.
Balustrade: A railing composed of balusters and a top rail running along the edge of a porch, balcony, roof, or stoop.
Banking Interior: The area of the designated interior historically used for banking operations and any associated interior spaces including, without limitation, entrance vestibules or mezzanines identified in the designation report as part of the designated interior.
Bay: A regularly repeating division of a façade, marked by fenestration.
Bay Window. A projecting form containing windows that rises from the ground or from some other support, such as a porch roof; see also oriel.
Block Plan: A drawing of a building’s foot print within an entire block in simplified, non-detailed form
Bracket: A projecting angled or curved form used as a support, found in conjunction with balconies, lintels, pediments, cornices, etc.
Bracket Sign: A rigid outdoor sign, with two display faces, installed perpendicular to a building facade and hanging from an armature, used as an announcement for an establishment in the building, consisting of the rigid display faces and all letters, words, numerals, illustrations, decorations, trademarks, emblems, symbols or their figures or characters associated with the name of the establishment that are applied to the faces. In addition, a bracket sign may consist solely of an outline of a shape and/or letters intended to act as a symbol or sign for the establishment.
Brick Molding: A milled wood trim piece covering the gap between the window frame and masonry, which can be rectilinear, curved, or composite-curved.
Bulkhead: The part of a storefront that forms a base for one or more display windows
Building Plan: A drawing that shows a horizontal view
Building Streetwall: The predominant plane of the building facade at the level of the storefront.
Came: A slender rod of cast lead, with or without grooves, used in casements and stained-glass windows to hold the panes or pieces of glass together
Canopy: A metal frame clad with fabric that projects from a building entrance over the sidewalk to the curb where it’s supported on vertical posts
Cap flashing: A waterproof sheet that seals the tops of cornices and walls.
Capital: The topmost member, usually decorated, of a column or pilaster.
Casement: A window sash that is hinged on the side.
Cast Iron: A type of iron, mass-produced in the nineteenth century, created by pouring molten iron into a mold; used for ornament, garden furniture, and building parts.
Clapboard Wood: Siding composed of horizontal, overlapping boards, the lower edges of which are usually thicker than the upper.
CNE: A Certificate of No Effect as defined by section 25-306 of the New York City Administrative Code.
Colonnade: A row of regularly spaced columns supporting an entablature.
Colonnette: A diminutive column which is usually either short or slender.
Color : The sensible perception of hue, value and saturation characteristics of surfaces of window components. In the event of disagreement, the Munsell system of color identification shall govern.
Column : A vertical, cylindrical support. In classical design it is composed of a base (except in the Greek Doric order), a long, gradually tapered shaft, and a capital.
Commission: The Landmarks Preservation Commission (LPC) as established by Section 3020 of the New York City Charter.
Commissioners: The 11 Commissioners, including the Chairman, as established by Section 3020 of the Charter. All are appointed by the Mayor.
Configuration: The number, shape, organization and relationship of panes (lights) of glass, sash, frame, muntins or tracery.
Console: A scroll-shaped projecting bracket that supports a horizontal member.
Coping: A protective cap, top, or cover of a wall parapet, commonly sloping to protect masonry from water
Corbel : An architectural member which projects upward and outward from a wall that supports a horizontal member.
Cornice: A projecting molding that tops the elements to which it is attached; used especially for a roof or the crowning member of an entablature, located above the frieze.
Cresting: A decorative element, frequently of iron, usually located at the peak or edge of a roof.
Crocket: An ornamental foliate form placed at regularly spaced intervals on the slopes and edges of the spires, pinnacles, gables, and similar elements of Gothic buildings.
Cupola: A small dome on a base crowning a roof
Day: Any day other than a Saturday or Sunday or legal holiday.
Decorative Masonry: Terra cotta, cast-stone or natural stone (such as limestone, marble, brownstone or granite) facade areas and/or any ornamental feature which is a component of the facade such as, belt courses, banding, water tables, cornices, corbelled brick work, medallions, enframements, and surrounds, and ornamental bonding patterns, e.g. tapestry brick or diaper patterns.
Demolition: Dismantling or razing of all or part of an existing improvement.
Dentil : A small, square, tooth-like block in a series beneath a cornice.
Details: The dimensions and contours of both the stationary and moveable portions of a window, and moldings.
Display Window: The large glazed portion of the storefront, and the associated framing, above the bulkhead and below the transom, extending from pier to pier. The display window is typically used for the display of goods and to provide daylight and visibility into the commercial space.
Doric: One of five classical orders, recognizable by its simple capital. The Greek Doric column has a fluted shaft and no base; the Roman Doric column may be fluted or smooth and rests on a molded base.
Dormer: A vertical structure, usually housing a window, that projects from a sloping roof and is covered by a separate roof structure.
Double hung: A type of window with two sash, each sliding on a vertical track.
Drip molding: A projecting molding around the head of a door or window frame, often extended horizontally at right angles to the sides of the frame, intended to channel rain away from the opening; also called a drip lintel.
Dunnage: Supports for air conditioning and other equipment above the roof of a building.
Eave: The overhanging edge of a roof.
Egg and dart. An ornamental band molding of egg forms alternating with dart forms.
Elevation: A drawing of a face of a building with all the features shown, as if in a single vertical plane
Enframement: A general term referring to any elements surrounding a window or door.
Engineer: Any individual, partnership, corporation or other legal entity licensed to practice the profession of engineering under the education law of the State of New York.
English bond: A pattern of brickwork with alternate courses of headers and stretchers.
Entablature: A major horizontal member carried by a column(s) or pilaster(s); it consists of an architrave, a frieze, and a cornice. The proportions and detailing are different for each order, and strictly prescribed.
Establishment: A manufacturing, commercial or retail business or profession.
Entrance recess: The recessed opening in the facade leading up to the doorway of a storefront or building entrance.
Existing windows: The windows existing at the time of designation or windows which have been changed subsequent to designation pursuant to a permit issued by the Commission.
Eyebrow dormer. A curved dormer with no sides, covered by a smooth protrusion from the sloping roof.
Façade: The main exterior face of a building, sometimes distinguished from the other faces by elaboration of architectural or ornamental details.
Fanlight: A semicircular or semielliptical window above a door, usually inset with radiating glazing bars.
Fascia: A horizontal, flat element often combined with a cornice and architrave.
Fenestration: The arrangement, proportioning and design of windows in a building.
Festoon: A carved ornament in the form of a band, loop, or wreath, suspended from two points; also called a “garland” or “swag”.
Finial. The crowning ornament of a pointed element, such as a spire.
Finish: The visual characteristics including color, texture and reflectivity of all exterior materials.
Fixture: An appliance or device attached to the facade (e.g. awning, sign, lighting fixture, conduit, or security gate).
Flashing: Strips of sheet metal bent to fit the angle between any two roof surfaces or between the roof and any projection, such as a chimney.
Floor Plan: A scaled drawing showing the horizontal arrangement of one level of the building that typically indicates walls, doors and dimensions
Flemish bond: A pattern of brickwork in which each course consists of headers and stretchers laid alternately; each header is centered between the stretcher above and the stretcher below it.
Foliate: Decorative leafage, often applied to capitals or moldings.
Frame: The stationary portion of a window unit that is affixed to the facade and holds the sash or other operable portions of the windows.
French door or French window: A tall casement window that reaches to the floor, usually arranged in two leaves as a double door.
Frieze: 1. The middle horizontal member of a classical entablature, above the architrave and below the cornice. 2. A similar decorative band in a stringcourse, or near the top of an interior wall below the cornice.
Gable: The upper portion of an end wall formed by the slope of a roof.
Galvanized Iron: Iron that has been coated with zinc to inhibit rusting.
Glazing: The material, usually glass, that fills spaces between sash members (rails, stiles and muntins), commonly referred to as panes or lights.
Glazing Bar: See mullion.
Gothic Sash : A window sash pattern composed of mullions that cross to form pointed arches.
Grille: A decorative, openwork grating, usually of iron, used to protect a window, door, or other opening.
Gutter: A shallow channel of metal or wood set immediately below and along the eaves of a building to catch and carry off rainwater.
Head : The upper horizontal part of a window frame or window opening.
Header: A masonry wall unit of brick which is laid so that its short end is exposed.
Historic Appearance: The visual appearance of a structure or site at a specific point in time after it has undergone alterations or additions which enhance or contribute to the building or site’s special architectural, aesthetic, cultural, or historic character.
Historic Fabric: A building's original or significant historic façade construction material or ornament, or fragments thereof.
Historic windows: (1) windows installed at time of construction of the building; or (2) windows of a type installed at time of construction of similar buildings in similar periods and styles; or (3) windows installed at time of major facade alterations 30 or more years ago.
Hood: A projection that shelters an element such as a door or window.
HVAC Equipment: Window, through-wall and yard-mounted heating, ventilation, and air conditioning equipment, including window louvers, wall-mounted grilles and stove, bathroom and/or dryer vents.
Improvement: Any building, structure, place, work of art, or other object constituting a physical betterment of real property, or any part of such betterment.
Ionic: One of the five classical orders, characterized by capitals with spiral elements called “volutes,” a fasciated entablature, continuous frieze, dentils in its cornice, and by its elegant detailing.
Jamb: The side parts of a window frame or window opening, as distinct from head and sill.
Jigsaw Carving: Wooden ornament cut with a thin narrow saw blade.
Joist : One of a series of parallel timber beams used to support floor and ceiling loads, and supported in turn by larger beams, girders, or bearing walls; the widest dimension is vertically oriented.
Key. A block, often used in a series, which projects beyond the edge of the enframement of an opening and is joined with the surrounding masonry. A block handled in such a manner is keyed to the masonry; see quoin.
Keystone. The central wedge-shaped member of a masonry arch; also used as a decorative element on arches in wood structures.
Landmarks Law: Refers to Section 3020 of the New York City Charter and Chapter 3 of Title 25 of the Administrative Code of the City of New York.
Landmarks Preservation Commission: The Commission acting in its agency capacity to implement the Landmarks Law.
Landscape improvement: A physical betterment of real property or any part thereof, consisting of natural or artificial landscaping, including but not limited to grade, terrace, body of water, stream, rock, hedge, plant, shrub, mature tree, path, walkway, road, plaza, wall, fence, step, fountain, or sculpture.
Latticework. Thin strips of wood arranged in a netlike grid pattern, often set diagonally.
Leaded window. A window composed of small panes, usually diamond-shaped or rectangular, held in place by narrow strips of cast lead.
Leade. A horizontal or vertical cylinder, usually made of metal, which carries water from the gutter to the ground.
Light. A pane of glass; a window, or a compartment of a window.
Lighting: The method or equipment for providing artificial illumination.
Lintel: A horizontal structural element over an opening which carries the weight of the wall above it.
Loggia: 1. An arcaded or colonnaded structure, open on one or more sides, sometimes with an upper story. 2. An arcaded or colonnaded porch or gallery attached to a larger structure.
LPC Staff: The staff of the Landmarks Preservation Commission acting in the Commission's agency capacity.
Lunette. A crescent-shaped or semicircular area or opening on a wall surface.
Mansard. A roof having a double slope on all four sides, the lower slope being much steeper. In rowhouse design, a double-sloped roof on the building front, below a flat roof.
Master plan: The term has two meanings: 1) a permit type issued to large residential or commercial buildings that sets a building-wide standard for future changes that could cover certain repetitive changes, such as window and air conditioner installation and 2) a set of rules created by the LPC that apply to historic districts and outline creteria for certain types of changes that can be approved under a staff-level permit.
Match. Either an exact or approximate replication. If not an exact replication, the approximate replication shall be so designed as to achieve a suitable, harmonious and balanced result.
Materials: The substances used to fabricate the various elements and details of a building
Mature tree: Any tree with a trunk diameter of 12" or greater.
Meeting rail: A sash rail in a double-hung window designed to interlock with an adjacent sash rail.
Mechanical equipment: Includes, but not be limited to, heating, venting and air conditioning equipment, water tanks and their supporting structures, satellite dishes, stair and elevator bulkheads, screens, dunnages, baffles and other accessory installations but shall not include telecommunication equipment and conventional television antennas. Mechanical equipment can also include unenclosed decks, garden trellises, or associated railings.
Member: A component part of a window.
Minimally Visible: Refers to any rooftop addition which when viewed from any public thoroughfare, projects into the maximum line of sight from such public thoroughfare by not more than 12 inches in height, or, due to its placement and size does not call attention to itself nor detract from any significant architectural features.
Modification: Any work to an existing improvement or landscape improvement other than (a) ordinary maintenance or repair; or (b) any Addition.
Modillion: A projecting scroll-shaped bracket or simple horizontal block arranged in series under the soffit of a cornice.
Molding: A piece of trim that introduces varieties of outline or curved contours in edges or surfaces as on window jambs and heads. Moldings are generally divided into three categories: rectilinear, curved and composite-curved.
Mullion: A vertical primary framing member that separates paired or multiple windows within a single opening.
Muntin: A tertiary framing member that subdivides the sash into individual panes, lights or panels. Note: Grids placed between two sheets of glass are not considered muntins.
Newel: The main post at the foot of a stairway or stoop.
Non-significant features: The interior architectural features of the designated interior that the LPC has determined do not contribute to the special historic, cultural, and/or aesthetic character for which the interior was designated. These features comprise all of the interior architectural features of the interior with the exception of those features that are underscored in the designation report.
Notice of Compliance: A letter or notice from LPC that certifies that completed work complies with a permit
Notice of Violation: A notice from the Landmarks Preservation Commission that work on a landmark site or within an historic district was performed without a permit or was not performed in accordance with a permit issued by the Landmarks Preservation Commission.
Oblique: View in which a three-dimensional object is represented by a drawing (oblique drawing) in which the face. usually parallel to the picture plane, is represented in accurate or exact proportion, and all other faces are shown at any convenient angle other than 90°.
Occupiable space: A room, or enclosure and accessory installations thereof, which are intended for human occupancy or habitation
Operation: The manner in which a window unit opens, closes, locks, or functions; e.g. casement, double-hung, etc. If non-operable, a window unit (such as a side light) is identified as "fixed."
Oriel: A projecting bay window carried on corbels or brackets.
Original appearance: The visual appearance of a structure or site at approximately the time of its completed initial construction.
Palladian Window: A three-part window opening with a tall, round-arched center window flanked by smaller rectangular windows and separated by posts or pilasters.
Panel: A portion of a flat surface recessed, or raised from the surrounding area, distinctly set off by molding or some other decorative device.
Panning: An applied material, usually metal, that covers the front (exterior) surface of an existing window frame or mullion
Parapet: A low wall that serves as a vertical barrier at the edge of a roof, terrace, or other raised area; in an exterior wall, the part entirely above the roof.
Parting strip: The small member, usually wood and usually removable, that separates the upper and lower sash pockets in the jamb of a double-hung window
Paver: A block of stone used in sidewalk or areaway paving.
Pediment: 1. The triangular space forming the gable end of a roof above the horizontal cornice. 2. An ornamental gable, usually triangular, above a door or window.
Permit: Any permit other than a Notice to Proceed issued by the Landmarks Preservation Commission in accordance with the Landmarks Law: (a) "PMW shall mean Permit for Minor Work as defined by Section 25-310 of the Landmarks Law. (b) "CNE shall mean Certificate of no Effect as defined by Section 25-306 of the Landmarks Law. (c) "CofA shall mean Certificate of Appropriateness as defined by Section 25-307 of the Landmarks Law.
Pier: 1. A column designed to support concentrated load. 2. A member, usually in the form of a thickened section, which forms an integral part of a wall; usually placed at intervals along the wall to provide lateral support or to take concentrated vertical loads. 3. A vertical supporting member or element (usually of brick, stone, or metal) placed at intervals along a wall, which typically separate each storefront opening from the adjacent storefront opening.
Pilaster: An engaged pier or pillar, often with capital and base.
Pitched: Sloping, especially referring to a roof.
Plinth: A platform base supporting a column or pilaster.
Pointing: The treatment of joints between bricks, stone, or other masonry components by filling with mortar; also, called tuck-pointing
Portico: A small porch composed of a roof supported by columns, often found in front of a doorway.
Post-1939 Building: Any building in the Riverdale Historic District built on or after January 1, 1940.
Pre-1940 Building: Any building in the Riverdale Historic District built, in whole or in part, prior to January 1, 1940 including buildings which have undergone subsequent remodeling and alterations.
Primary Façade: A facade facing a street or a public thoroughfare that is not necessarily a municipally dedicated space, such as a mews or court.
Principal Façade: A facade facing a street or a public thoroughfare that is not necessarily a municipally dedicated space, such as a mews or court.
P.S.I. Pounds per square inch, a term generally used when describing water pressure when cleaning a building
Public Thoroughfare: Any publicly accessible right of way including, but not limited to a street, sidewalk, public park, and path.
Quoin A structural form, usually of masonry, used at the corners of a building for the purpose of reinforcement, frequently imitated for decorative purposes.
Rail. A horizontal sash member.
Relief. Carved or molded ornament that projects from a flat surface.
Rehabilitation Any repair work that requires a permit.
Repair Any work done on any window to correct any deterioration or decay of or damage to a window or any part thereof and to restore same, as closely as may be practicable, to its condition prior to the occurrence of such deterioration, decay or damage. The term "ordinary repair" shall refer to work that does not require a permit.
Repointing : Process of renewing mortar joints; see pointing
Residential Awning: Any awning on a residential building and any awning on a commercial or mixed-use building except for storefront awnings.
Restoration: The process of returning, as nearly as possible, a building or any of its parts to its original form and condition.
Retractable Awning. An awning attached to a frame which allows it to be extended out or folded or rolled back tight against the building façade
Return: The part of a molding cornice, or wall surface that changes direction, usually at a right angle, toward the building wall.
Reveal: The side of an opening for a door or window between the frame and the outer surface of a wall, showing the wall’s thickness.
Reversible Alteration: An alteration in which the altered feature can be readily returned to its appearance prior to the alteration.
Roof Plan: A drawing showing the arrangement of fixtures on the roof
Rooftop addition: A construction or an installation of mechanical equipment and/or occupiable space situated on any structure's roof.
Rock-faced: Masonry treated with a rough surface that retains or simulates the irregular texture of natural stone.
Roll-down gate: A security gate with a mechanism that allows it to roll up and down.
Rosette: A round floral ornament, usually carved or painted.
Round arch: A semicircular arch.
Rowhouse: One of a group of an unbroken line of attached houses that share common side walls, known as party walls.
Rubble stone: Irregularly shaped, rough-textured stone laid in an irregular manner.
Rustication: Rusticated stonework composed of large blocks of masonry separated by wide, recessed joints; often imitated in other materials for decorative purposes.
Sash: The secondary part of a window which holds the glazing in place; may be operable or fixed; usually constructed of horizontal and vertical members; sash may be subdivided with muntins.
Scissor Gate: A security gate with a sideways retractable mechanism.
Secondary Façade: A facade that does not face a public thoroughfare or mews or court and that does not possess significant architectural features.
Section Drawing: A drawing representing a vertical plane cut through the structure
Security gate: A movable metal fixture installed in front of a storefront or inside the display window or door to protect the store from theft or vandalism when the store is closed. A security gate can be either the roll-down or scissor variety.
Security gate housing: The container that houses the rolling mechanism of a roll-down security gate.
Security gate tracks. The interior or exterior tracks along the sides of the storefront (for roll-down gates) or along the top and bottom of the storefront (for scissor gates) that hold the edges of the gates.
Segmental arch. An arch that’s in the form of a segment of a semicircle
Segmental or Curved-Head Window: A window with a non-rectilinear sash or frame as illustrated and defined as a special window in Appendices A and C of Chapter 3 of these rules.
Semi-detached: A building attached to a similar one on one side but unattached on the other.
Shaft: The vertical segment of a column or pilaster between the base and the capital.
Shed Dormer: A dormer window covered by a single roof slope without a gable.
Shingle: A unit composed of wood, cement, asphalt compound, slate, tile or the like, employed in an overlapping series to cover roofs and walls.
Shouldered Arch: An arch composed of a square-headed lintel supported at each end by a concave corbel.
Shutter Dogs: The metal attachments which hold shutters in an open position against the face of a building.
Sidelight: A vertically framed area of fixed glass, often subdivided into panes, flanking a door.
Sight line drawing: A drawing representing an uninterrupted view from eye level
Sign: A fixture or area containing lettering or logos used to advertise a store, goods, or services.
Signage : Any lettering or logos in general, used to advertise a store, goods, or services.
Sign band: The flat, horizontal area on the facade usually located immediately above the storefront and below the second story window sill where signs were historically attached. A sign band may also occur within a decorative bandcourse above a storefront.
Significant Feature: An exterior architectural component of a building that contributes to its special historic, cultural, and/or aesthetic character, or in the case of an historic district, that reinforces the special characteristics for which the historic district was designated.
Significant landscape improvement: Any landscape improvement which is a character-defining element in its historic district, contributing to the special aesthetic and historic character for which the district was designated, and including but not limited to those landscape improvements identified as landscape features in the designation report.
Sill: 1.The lower horizontal part of a window frame or window opening; also the accessory member which extends as a weather barrier from frame to outside face of wall. 2. The horizontal member at the bottom of a window or door.
Site Plan: A drawing of the footprint of the subject building and immediate adjacent buildings indicating the location of the proposed work.
Skirt: A bottom finishing piece of fabric that hangs from the lower edge of an awning.
Soffit: 1. The exposed underside of any architectural element, especially a roof. 2. The underside of a structural component such as a beam, arch, or recessed area.
Spalling: The chipping or erosion of masonry caused by abuse or weathering
Spandrel: 1. A panel between the top of one window and the sill of another window on the story directly above it. 2. An irregular, triangular wall segment adjacent to an arched opening.
Spandrel Area: The portion of the facade below the sill of an upper story window and above the lintel of the window or display window directly below it or above the lintel of a window or display window and the building cornice or top of building.
Special Natural Area District: A district designated by the New York City Planning Commission pursuant to Article X, Chapter 5 of the New York City Zoning Resolution which is mapped in areas where outstanding natural features or areas of natural beauty are to be protected.
Special windows: (1) those windows in which the complexity of the muntin pattern or the molding profiles is one of the characteristics of the style and age of the building; or (2) windows having one or more of the following or similar attributes, including but not limited to: (i) Bay or oriel window (ii) Curved glass (iii) Multi-pane sash, i.e. 12 or more panes in a single sash in which a typical pane does not exceed 30 square inches of open (glazed) area (iv) Stained or otherwise crafted glazing for artistic effect (v) Highly decorated (carved or otherwise embellished) sash or frame (vi) Non-rectilinear sash or frame.
State-of-the-Art Banking Change:
A physical alteration to the bank interior that the applicant has determined to be necessary to accommodate changes in technology and/or banking practice
Stile: A main vertical member of a door or window
Stoop: The steps which lead to the front door; from the Dutch “stoep.”
Storefront: The first story area of the façade that provides access or natural illumination into a space used for retail or other commercial purposes.
Storefront Bay: The area of the storefront defined by and spanning the two piers.
Storefront Infill: The framing, glazing, and cladding contained within a storefront opening in the facade.
Storefront Opening: The area of the facade framed by the piers and lintel, which contains storefront infill
Story: A habitable floor level, including a basement but not including a cellar.
Stretcher: A masonry unit or brick laid horizontally with its length parallel to the wall.
Stringcourse: A narrow horizontal band of masonry, extending across the façade, which can be flush or projecting, and flat surfaced, molded, or richly carved.
Stucco: A coating for exterior walls made from Portland cement, lime, sand, and water.
Subframe: A secondary frame set within a masonry opening.
Sugaring: A term describing the deterioration of stone caused by the breaking up or dissolving of the stone surface.
Surround: The ornamental frame of a door or window.
Swag: A carved ornament in the form of a draped cloth or a festoon of fruit or flowers.
Terra cotta: Hard fired clay, either glazed or unglazed, molded into ornamental elements, wall cladding, and roof tiles.
Tie rod: A metal tension rod connecting two structural members, such as gable walls or beams, acting as a brace or reinforcement; often anchored by means of a metal plate in such forms as an “S” or a star.
Tracery. An ornamental configuration of curved mullions in a Gothic sash.
Transom: 1. A horizontal bar of wood or stone across a window. 2. The cross-bar separating a door from the window, panel, or fanlight above it. 3. The window above the transom bar of a door. 4. The glazed area above a display window or door separated from the main window area or door by a transom bar.
Transom bar. A horizontal element that subdivides an opening, usually between a door and window.
Trefoil. A three-lobed decorative form used in Gothic architecture
Tuck-Pointing: See pointing.
Turret. A small tower, usually supported by corbels.
Volute. A carved spiral form in classical architecture; often used in pairs as in the capitals of Ionic columns.
Voussoir: A wedge-shaped component of an arch.