Glossary of Terms

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

• A

• Alteration
  Any change to the exterior of a building, structure, object or site. Alteration shall include, but is not limited to, changing to a different kind, type or size of roofing or siding materials; changing, eliminating, or adding exterior doors, door frames, windows, window frames, shutters, railings, columns, beams, walls, porches, steps, porte-cocheres, balconies, or ornamentation; or the dismantling, moving or removing of any exterior feature. Alteration includes expanding an existing structure or the construction of an addition to an existing structure.
• Arch
  A curved construct spanning an opening, which is supported by and rests upon two points; often supports overhead weight.
• Architrave
  The beam that makes up the bottom band of the entablature and rests directly on the capital of the column. The surface of the beam is often filled with decorative or ornamental moldings. 2: A set of ornamental moldings that border a rectangular opening, such as a door.
• Awning
  An overhang or covering placed on the exterior of a building, often above the upper edge of an opening or window; often functions to provide shade, filter light, or provide shelter from weather.

• B

• Balloon Frame
  A structural system developed in the United States that became popular through the industrialization of lightweight manufactured wood, metal upright studs and horizontal joists. The interspaced studs and joists are joined, often with nails, into an enclosed form to act as a structural skeleton.
• Baluster
  A vertical shaft or post, the form of which may be square, lathe-turned, or molded; often used to support the handrail of a porch or staircase. Also known as a spindle.
• Balustrade
  Balusters set in a series along a horizontal or inclined surface, functioning as a barrier or protective boundary.
• Batten
  A thin strip of lumber often used to seal a seam.
• Bay Window
  An angled or curved projection (often inset with glazing) from the exterior plane of a building or house.
• Beam
  A horizontal structural element that transfers the load of a building or structure to a foundation or to posts/piers set into the ground.
• Block
  One or more lots, tracts, or parcels of land bounded by streets, easements, rights-of-way, or other physical features or a combination thereof.
• Blockface
  The portion of a block that abuts a street.
• Brace
  A diagonally positioned structural element used as a support between horizontal and vertical structural members.
• Bracket
  A building element (often a piece of wood or stone) used to support or strengthen an overhanging element, such as the eave of a roof; also, a decorative element that appears to be, but does not function as, a structurally supporting member.
• Building
  Any structure used or intended for supporting or sheltering any use or occupancy.
• Building Permit
  An official document or certificate issued by the building official authorizing performance of a specified activity, including the alteration, restoration, rehabilitation, construction, relocation or demolition of a building, structure or object.

• C

• Capital
  The uppermost component of a column or pilaster, sometimes based on ancient Greek or Roman examples; design may be intricate or plain.
• Casement
  A metal or plastic frame into which a plane of glass is inserted into a window construct or sash, where the panel is made operable by a set of hinges on one edge of the frame.
• Casing
  The decorative molding around an opening such as a window or door.
• Certificate of Appropriateness
  A current and valid permit issued by the HAHC or the director, as applicable, authorizing the issuance of a building permit for construction, alteration, rehabilitation, restoration, relocation or demolition required by this article.
• Chimney
  A vertical structure used to draw air into a combustion chamber such as a fireplace, stove, or furnace and then ventilate the resulting smoke and gases to the outside atmosphere; made up of a shaft ( single flue)or a stack (multiple flues).
• Cladding
  The lightweight material used to cover the exterior surface of a load-bearing structure for aesthetic reasons or as a shield from the weather.
• Clapboard
  A narrow, horizontally laid board with one edge thinner than the other, attached to an exterior surface so that the wide edge of each board overlaps the thin edge of the board just below it. Traditionally made of wood, clapboard siding has more recently begun to be created using vinyl, aluminum, and cementitious fiber-board.
• Column
  A building element made up of a load-bearing base which supports a vertical shaft, topped with a capital. Columns are generally cylindrical or rectangular; they may be fluted, tapered, or otherwise shaped in a decorative manner. Bases and capitals are usually wider than the shaft in order to effectively distribute load. A column may be freestanding, but is more often used to structurally support a horizontal beam.
• Construction
  The act of expanding an existing building, structure or object or the erection of a new building, structure or object on a lot, site or other property.
• Contributing Structure
  A building, structure, object or site that reinforces, or that has conditions, which, if reversed, would reinforce, the cultural, architectural or historical significance of the historic district in which it is located, and that is identified as contributing upon the designation of the historic district in which it is located. The term also includes any structure that was identified as "potentially contributing" in any historic district designated prior to October 13, 2010.
• Corinthian Order
  One of the three principal classical orders of Greek and Roman architecture, the column often exhibits thin fluting along its length stopping short of the base, and a highly ornamented capital.
• Cornerstone
  The first stone laid at the intersection of two walls, forming the foundation of the building. This stone is often laid at a formal ceremony.
• Cornice
  The molded projection placed at the edge of the top of the wall, entablature, or roof, thereby finishing, or crowning, the structure.
• Cross Gable
  A roof shape that features two sets of gables; one set facing the front and back of the house and the other facing the sides, which cross to form a right angle.

• D

• Demolition
  An act or process that destroys in whole or in part any building, structure, object or site.
• Dentil
  A series of small rectangular or square blocks of stone or wood that trim the edge of a cornice in Ionic, Corinthian, and Composite Orders.
• Design Guidelines
  An inventory and analysis of historic resources within a geographic area of the city designated or proposed for designation as an historic district pursuant to the provisions of this article that contains standards for alteration, rehabilitation, restoration, construction, relocation and demolition of buildings, structures, objects or sites in an historic district, and approved by the city council.
• Designation
  The formal recognition by the city council of a building, structure, object, site or district as historically, architecturally, culturally or archaeologically significant to the city, state, nation or region.
• Doric Order
  The least ornate column construct, beside the Tuscan order, of the three original classical Greek and Roman orders; made up of a base, shaft, capital, and entablature.
• Dormer
  A building element that projects from a sloping roof surface, often inset with a window or vent to provide light and ventilation to a room or attic space.
• Double-Hung Sash Window
  A window having two panels (sashes), each of which is framed to hold one or more panes of glass, and both of which can be moved up and down.

• E

• Eave
  The overhanging lower edge of a roof.
• Elevation
  One vertical side of a building or structure.
• Exterior Feature
  An element of the architectural character and general arrangement of the external portion of a building, structure or object, including building material, that is visible from a public right-of-way.

• F

• Façade
  The exterior surface (often front-facing) of a building or construct.
• Fascia
  A band of molding that runs horizontally along the uppermost edge of a wall, just below the eave.
• Fenestration
  The system (arrangement and proportioning) of openings penetrating an exterior wall system; also, an opening in an exterior surface or membrane.
• Fluting
  The slender, vertical grooves, often shallowly inset along the shaft of a column, pilaster or other surface.
• Foundation
  The ground beneath a building; or, the base supporting structure beneath a building or structure, which transfers loads to the ground.
• Fretwork
  A decorative design cut out of a solid piece of material or carved in low-relief on a solid background; may be a geometric, grid, lattice or intertwined pattern.
• Frieze
  An ornamental band, often positioned just below the cornice and above the architrave, with its surface sometimes filled with bas-relief sculpture or left empty.
• Front Façade
  The elevation of a building that is parallel to an adjacent public right-of-way, on a corner lot, or lot adjacent to more than one public right-of-way;also contains the main entrance to the building.

• G

• Gable-on-Hip
  A roof structure in which a steeply-sloped gable roof rests upon and extends from the top central surface of a hipped roof.
• Gable
  The generally triangular portion of a wall between the two sloped edges of a roof. Multiple gable shapes exist.
• Gambrel
  A bilateral roof formation in which two slopes are used, the upper slopes shallow and the lower slope steep.
• Glazing
  A transparent pane, made of glass or plastic, which is set into a window sash or a door; often set into a groove within the frame and secured with triangular glazing points, putty or molding.

• H

• HAHC
  The Houston Archaeological and Historical Commission.
• Handrail
  A rail attached firmly to a surface or supporting structure, designed to be grasped for added stability.
• Header
  The brick laid within a wall so that the short end is exposed and the wide side is parallel to the ground.
• Hip-on-Gable
  A roof structure in which the peak of a gable roof, instead of rising to a point, is clipped short and appears to turn downward. Also known as a clipped gable or jerkinhead.
• Hipped Roof
  A roof structure in which all sides slope down from a central peak or ridge, and the sides also meet at ridges.
• Historic District
  A geographical area designated by the city council that possesses a significant concentration, linkage or continuity of buildings, structures, objects or sites united by historical, cultural, architectural or archaeological significance to the city, state, nation or region.

• I

• Ionic Order
  The second of the three original classical orders; distinguished by mellifluous volutes in its capital resting atop the shaft and base of the column.

• J

• Jamb
  The vertical piece or surface that forms the side of an opening, such as a window, door or vault.
Joist
A structural member laid horizontally in a series from wall to wall or beam to beam, to support the weight of a floor, ceiling or roof. Joists may be made of wood, metal or concrete.
Keystone
The vertical wedge-like architectural piece set at the crown of an arch or vault, designed to lock the other pieces into position.
Landmark
Any individual building, structure, object or site designated by the city council for its historical, cultural, architectural or archaeological significance in the city, state, nation or region.
Latticework
A decorative panel made of thin strips of material in a criss-crossed pattern.
Lite (or Light)
A piece or section of glass, set within a frame in a window or door. A single window unit may have multiple lites, which may be individual panes of glass or a single piece of glass visually divided by false muntins.
Lintel
A horizontal beam that carries the load above an opening, such as a window or door.
Louvers
Horizontal slats or fins, sometimes movable, which are set into an opening at a slant to admit light and air but keep out rain.
Mandatory Repair
A repair of a building or structure that is necessary to comply with Article IX of Chapter 10 of Houston Code of Ordinances as evidenced by an order of the hearing official or the building and standards commission or by a citation.
Mansard
A roof of French origins such that each side is made up of two slopes, the lower slope steeper than the upper slope.
Modillions
Small ornamental blocks or brackets that run along the length of the underside of a cornice, just above the bedmold, as often seen with Corinthian orders.
Molding
A decorative strip of material placed atop a surface for ornamental or finishing purposes.
Mullion
A vertical bar of a metal, wood, or stone that separates adjacent window units in a row of windows.
Muntin
A thin vertical strip of wood or metal used to separate and hold in place the panes of glass within a window sash.
Noncontributing Structure
A building, structure, object or site that does not reinforce the cultural, architectural, or historical significance of the historic district in which it is located, and is identified as noncontributing upon the designation of the historic district in which it is located.
Object
A material thing of a functional, aesthetic, cultural, historical or scientific value that may be moveable by nature or design, yet related to a specific setting or environment.
Ordinary Maintenance and Repair
Any work to correct or prevent deterioration, decay or damage to a building, structure, object or site (or any part thereof), including but not limited to painting or adding or replacing fences, provided that the work does not change the design, character, texture or material of any exterior feature or constitute an 'alteration' as defined above.
Ornament
A building element that is decorative rather than structural; may be used to conceal structural elements, indicate the function of a part of the building, or express a particular style or type of design.
Panel
A flat or raised surface, usually set into a frame.
Parapet
A low wall bounding the precipice of any surface, e.g., bridge edge or house-top.
Pedestal
The base or block beneath a structural or decorative element, essentially structurally supporting the object above.
Pediment
The enclosed triangular surface bound above by the members on the end of a pitched roof and below by the members of the entablature. The surface is often filled with bas-relief sculpture or left blank. The straight or curved feature is often used just above door and windows.
Pent Roof
A roof structure composed of a single slope.
Pergola
A structure composed of a pillars or posts supporting beams and latticework from which woody vines and foliage grow as a shading device for objects within its scope.
Pier
A post constructed of masonry units. See post.
Pier-and-Beam
(Please refer to entry for Post-and-beam)
Pilaster
A shallow, often rectangular decorative element applied to the vertical surface of a wall, in order to create the look of a column without providing structural support.
Pinnacle
The uppermost section of an element.
Pitch
The slope of a surface, e.g., a roof.
Plate Glass
A flat sheet of glass, such as may be inserted into a window or door.
Plate Height
The distance from the subfloor of a building to the top of the framed wall.
Porch
A raised, usually unenclosed platform attached to one or more sides of a building and used primarily as a sitting area, outdoor living space, or covered access to a doorway.
Porte Cochère
A covered structure attached to a building, through which a vehicle can pass, which allows passengers to exit vehicles and enter the building under cover and out of the weather.
Portico
A central façade element, open or partially enclosed, attached to the front of an entrance composed of a pediment and columns.
Post
A vertical structural element that supports a horizontal structural element (beam) laid across its upper ends.
Post-and-Beam
A simple type of construction system, composed of vertical structural members that support a horizontal structural member.
Protected Landmark
A landmark whose owner has elected to permanently protect the landmark by foregoing the 90-day waiver certificate authorized by this article.
Public Right-of-Way
An area dedicated to the public for the passage of people or goods.
Pylon
A rectangular, shortened, or pyramidal member used to designate an opening or mark a boundary.
Pyramidal Roof
A type of hipped roof with a square base and four sides that meet at a central peak.
Quoins
Masonry or stone blocks at the corner of a wall; may be structural or simply decorative; often laid so that they appear to wrap around the corner with alternating short and long sides.
Rafter
A structural member that rets on the top of a wall or other supporting surf ace and rises at a slope to the ridge or peak of the roof; a series of rafters supports the roof deck and eaves.
Rafter Tail
The exposed end of a rafter, which may extend to or beyond the edge of the roof eave.
Rehabilitation
The act or process of returning a building, structure, object or site to a state of utility that makes possible an efficient contemporary use while preserving those portions or exterior features that are historically, architecturally and culturally significant.
Relocation
Any change in the location of a building, structure or object.
Restoration
The act or process of accurately recovering the form and details of a building, structure, object or site and its setting as it appeared at a particular period of time by the removal of later work, or by the replacement of missing earlier work or both.
Ridge Board
The horizontal beam at the central apex of a roof, to which the upper end of the rafters are attached.
Roof Pitch
The slope of a roof surface expressed in inches of vertical rise per twelve inches of horizontal distance.
Sash
Narrow pieces of material, (i.e.wood, metal, or plastic) often used to frame the glazing inset into an opening, such as in a window, capable of being fixed or moved.
Shingle
A standardized, wedge-shaped piece of wood or asbestos/cement material used in overlapping courses to provide a weatherproof covering on a roof or wall structure; may be cut into shapes (e.g., square, fish-scale, octagon, staggered, diamond, cove) to form patterns.
Shiplap
A type of board lumber fabricated with overlapping edge rabbit joints; often used as a supporting member and siding found on the interior of historic wood frame houses.
Sill
The horizontal structural member at the base of a wall, window or door opening, to which vertical members (such as studs or posts) are attached.
Site
Property upon which a significant event occurred, including, but not limited to, any land, building or natural resource where prehistoric or historic occupations or activities occurred and the location of buildings and structures, whether standing, ruined, demolished or relocated, where the location retains historical, architectural or archaeological value and integrity.
Slab
A flat concrete plate, often reinforced with steel rebar, that forms the floor of a building.
Soffit
The underside of a construction element, such as a roof eave.
Spandrel
The material that fills the space between the exterior of two arches from the apex at the top of the arch to the point at which they meet on the side. The arches may be positioned at a 90 degree angle or in a single plane.
Step
Part of a stairway, consisting of a tread (horizontal piece upon which one steps) and a riser (the vertical piece between steps).
Stoop
A small staircase leading to the entrance of a building.
Structure
That which is built or constructed, an edifice or building of any kind, or any piece of work artificially built up or composed of parts joined together in some definite manner.
Stucco
A decorative exterior wall coating usually made of lime, Portland cement, sand, water and other materials that add strength and flexibility; frequently applied over a metal or plastic mesh that helps the stucco bond to the wall material.
Transom
The horizontal crossbar over a door or window (also known as a lintel); also, a window above a door or other window, which rests upon and may be hinged to the transom.
Trim
Material used to decorate or frame a building façade or an opening, such as a door or window.
Truss
A structural system made of straight wooden or metal members arranged into triangular units; typically used in a bridge building or to support a roof, because a truss can carry heavier loads and span greater distances than a simple beam.
Veneer
A thin slice of wood or a relatively thin single width of brick, stone or masonry used to cover a surface.
Veranda
A porch that lines the exterior of a building on one or more sides, often partially enclosed by a railing and a series of columns or posts.
Verge Board
An ornamental board attached to the projecting edge of a gable roof; also known as a barge board.
Vestibule
The small chamber set off to the side of an entrance.
Volute
A sculptural element, consisting of curls of stone or wood, that adorn the base of a capital, found especially on the Ionic, Corinthian, and Composite orders.
Water Table
The architectural feature that consists of a projecting drip mold on the surface of a wall for the purpose of preventing moisture from creeping up the rear of the cladding surface. The water table is often positioned horizontally at the base of a building or at the juncture between two materials.
Weep Hole
An opening built into an exterior masonry wall, which allows water to pass from inside a wall system to the outside.
Wing
An extension or addition to an existing or main building.