back-nailing: The practice of nailing roofing felts to the deck under the overlap, in addition to hot-mopping, to prevent slippage of felts.
backer rod: In glazing, a polyethylene or polyurethane foam material installed under compression and used to control sealant joint depth, provide a surface for sealant tooling, serve as a bond breaker to prevent three-sided adhesion, and provide an hourglass contour of the finished bead.
backfill: The slope of the ground adjacent to a house. The replacement of excavated earth into a previously excavated area, such as a trench around and against a basement foundation. In carpentry, the process of fastening together two pieces of board by gluing blocks of wood in the interior angle.
backflow: Movement of water (or other liquid) in any direction other than that intended.
backflow preventer: A device or means to prevent backflow of contaminated water into the potable water supply.
backhand: A simple molding sometimes used around the outer edge of plain rectangular casing as a decorative feature.
backhoe: Self-powered excavation equipment that digs by pulling a boom-mounted bucket toward itself, and used to dig basements and footings, and to install drainage and sewer systems.
backout: Work that the framing contractor does after the mechanical subcontractors (heating, plumbing and electrical) finish their phase of work at the rough stage (before insulation) to get the home ready for a municipal frame inspection. Generally, the framing contractor repairs anything disturbed by others and completes all framing necessary to pass a Rough Framing Inspection.
backsplash: The raised portion of tile, stone, etc., located at the rear of a wall-mount sink or lavatory that is installed to protect the wall behind.
balancing damper: Baffle or plate used to control the volume of air flow into a confined area.
balcony: An exterior floor projecting from and supported by a structure without additional independent supports.
balloon framing: In carpentry, the lightest and most economical form of construction in which the studding and corner plates are set up in continuous lengths from the first floor line or sill to the roof plate to which all floor joists are fastened.
balusters: The vertical members in a railing installed between the top rail and bottom rail or stair treads.
balustrade: A railing made up of balusters, top rail and sometimes bottom rail, used on the edge of stairs, balconies and porches.
band joist: Dimensional lumber used as a perimeter joist of a building’s framing.
barge: Horizontal beam rafter that supports shorter rafters.
barge board: A decorative board covering the projecting rafter (fly rafter) of the gable end. At the cornice, this member is a fascia board.
barometer: An instrument that measures atmospheric pressure.
barrel roof: A roof design that in cross-section is arched.
base flashing: The upturned edge of a watertight membrane formed at a roof’s termination point by the extension of the felts vertically over the cant strip and up the wall for a varying distance, where they are secured with mechanical fasteners.
base molding: Molding used to trim the upper edge of interior baseboard.
base ply: An asphalt-saturated and/or -coated felt installed as the first ply with 4-inch laps in a built-up roof system under the subsequent courses of felt, which can be installed in a shingle-like fashion.
base shoe: Molding used next to the floor on interior base board, sometimes called a carpet strip.
baseboard: Wood or vinyl installed around the perimeter of a room to cover the space where the wall and floor meet; a board placed against the wall around a room next to the floor to properly finish the area between the floor and the plaster.
baseboard heat: An electric or hot-water heating system whose heating unit is located along the perimeter of the wall where the baseboard would normally be located.
basement: That portion of a building that is partly or completely below grade.
basement wall: A wall that is mostly below grade.
basement window insert: The window frame and glass unit that is installed in the window buck.
basket strainer: Basket-shaped strainer for a sink drain that has holes which allow water to drain while catching food and other solids. Can also be closed to fill the sink with water.
bathroom: A room containing plumbing fixtures, including a lavatory/sink, water closet, urinal, bidet, bathtub and/or shower.
batt insulation: Strips of (typically) fiberglass insulation that fit between studs and other framing.
batten: Narrow strips of wood used to cover joints and/or as decorative vertical members over plywood or wide boards.
batten plate: A formed piece of metal designed to cover the joint between two lengths of a metal edge.
batter board: One of a pair of horizontal boards nailed to posts set at the corners of an excavation used to indicate the desired level, and also used as a fastening for stretched strings to indicate the outlines of foundation walls.
batter boards: Temporary structures that hold strings used to locate and square the corners of a building.
bay window: A window space projecting outward from the walls of a building, typically square or polygonal in plan.
bead: In glazing, an applied sealant in a joint, irrespective of the method of application, such as caulking bead, glazing bead, etc.; also, a molding or stop used to hold glass or panels in position.
beam: A supporting member of wood or steel; structural support member (of steel, concrete, lumber, etc.) transversely supporting a load that transfers weight from one location to another.
bearing header: (a) A beam placed perpendicular to joists and to which joists are nailed in framing for a chimney, stairway or other opening. (b) A wood lintel. (c) The horizontal structural member over an opening, such as a door or window.
bearing partition: A partition that supports any vertical load in addition to its own weight.
bearing point: A point where a bearing or structural weight is concentrated and transferred to the foundation.
bearing wall: A wall that supports any vertical load in addition to its own weight.
bed molding: A molding in an angle, as between the overhanging cornice or eaves of a building and its side walls.
bed, bedding: In glazing, the bead compound or sealant applied between a lite of glass or panel and the stationary stop or sight bar of the sash or frame. It is usually the first bead of compound or sealant to be applied when setting glass or panels.
bedrock: A sub-surface layer of earth that is suitable for supporting a structure.
bedroom: A room used for sleeping purposes.
bell reducer: In plumbing, a bell-shaped fitting that has one opening of a smaller diameter used to reduce the size of the pipe in the line, with its opposite opening of larger diameter.
below grade: Describes the portion of a building that is below ground level.
bent glass: Flat glass that has been shaped during manufacture into curved shapes.
bevel: The angle of the front edge of a door, usually from 1/8-inch to 2 inches.
bevel siding: Wedge-shaped boards installed in a lapped pattern used as horizontal siding. This siding varies in butt thickness from 1/2-inch to 3/4-inch and in widths up to 12 inches, and is normally installed over some type of sheathing. Also called lap siding.
bid: A formal offer by a contractor, in accordance with specifications for a project, to do all or a phase of the work at a certain price, in accordance with the terms and conditions stated in the offer.
bid bond: A bond issued by a surety on behalf of a contractor that provides assurance to the recipient of the contractor’s bid that, if the bid is accepted, the contractor will execute a contract and provide a performance bond. Under the bond, if the bid is accepted and the contractor fails to execute the contract or to provide a performance bond, the surety is obligated to pay the recipient of the bid the difference between the contractor’s bid and the bid of the next lowest responsible bidder.
bid documents: Drawings, details and specifications for a particular project.
bid security: Funds or a bid bond submitted with a bid as a guarantee to the recipient of the bid that the contractor, if awarded the contract, will execute the contract in accordance with the bidding requirements of the contract documents.
bid shopping: A practice by which contractors, both before and after their bids are submitted, attempt to obtain prices from potential subcontractors and material suppliers that are lower than the contractors’ original estimates on which their bids are based, or after a contract is awarded, seek to induce subcontractors to reduce the subcontract price included in the bid.
bidding requirements: The procedures and conditions for the submission of bids. The requirements are included on documents, such as the notice to bidders, advertisements for bids, instructions to bidders, invitations to bid, and sample bid forms.
bidet: A toilet-like plumbing fixture designed to promote posterior hygiene; not a toilet.
bifold doors: Doors that are hinged in the middle to allow them to open in a smaller area than standard swing doors, typically used for closet doors in residential installations, and kitchen doors separating the kitchen from the dining area in commercial installations.
binder: A receipt from a seller for a deposit from a buyer that secures the right to purchase a home under agreed-upon terms.
bird’s-mouth cut: A cutout in a rafter where it crosses the top plate of a wall, providing a bearing surface for nailing. Also called a heel cut.
bite: The dimension by which the framing system overlaps the edge of the glazing infill.
bitumen: Refers to any of a variety of mixtures of hydrocarbons occurring naturally or obtained through the distillation of coal or petroleum. (See also coal tar pitch and asphalt).
blankets: Fiberglass or rock-wool insulation that comes in long rolls 15 or 23 inches wide.
bleeding: The migration of a liquid to the surface of a component or into/onto an adjacent material.
blind nailing: Nailing in such a way that the nail heads are not visible on the face of the work, usually at the tongue of matched boards.
blind stop: A rectangular molding, usually 3/4-inch by 1-3/8 inches or more in width, used in the assembly of a window frame, serving as a stop for storm and screen or combination windows and to resist air infiltration.
blister: An enclosed raised spot evident on the surface of a building, mainly caused by the expansion of trapped air, water vapor, moisture or other gases.
block out: To install a box or barrier within a foundation wall to prevent the concrete from entering an area. Foundation walls are sometimes blocked in order for mechanical pipes to pass through the wall, to install a crawlspace door, or to depress the concrete at a garage door’s location.
blocked (door blocking): Wood shims used between the door frame and the vertical, structural wall framing members.
blocked (rafters): Short 2x4s used to keep rafters from twisting, and installed at the ends and at mid-span.
blocking: In carpentry, the process of fastening together two pieces of board by gluing blocks of wood in the interior angle.
blown-in insulation: Fiber insulation in loose form used to insulate attics and existing walls where framing members are not exposed.
blue stain: A bluish or grayish discoloration of sapwood caused by the growth of certain mold or other fungi on the surface and in the interior.
blue stake: A utility company (telephone, gas, electric, cable TV, sewer and water, etc.) locating and spray-painting the ground and/or small flags inserted in the ground to show where their service is located underground. Also called utility notification.
blueprints: Architectural plans for a building or construction project typically including floor plans, footing and foundation plans, elevations, plot plans, and various schedules and/or other details.
board and batten: A method of siding in which the joints between vertically-placed boards or plywood are covered by narrow strips of wood.
board foot: The volume of a piece of wood measuring 12 inches square and 1 inch thick. A piece of lumber that is 1/2-inch thick, 6 inches wide and 24 inches long is equal to 1 board foot.
boards: Yard lumber less than 2 inches thick and 2 or more inches wide.
bodied linseed oil: Linseed oil that has been thickened in viscosity by suitable processing with heat or chemicals. Bodied oils are obtainable in a great range in viscosity, from a little greater than that of raw oil to just short of a jellied condition.
boiled linseed oil: Linseed oil in which enough lead, manganese or cobalt salts have been incorporated to make the oil harden more rapidly when spread in thin coatings.
bolster: A short horizontal timber or steel beam on top of a column that supports and decreases the span of beams or girders.
bond breaker: A substance or a tape applied between two adjoining materials to prevent adhesion between them.
bond plaster: In addition to gypsum, bond plaster used as a base coat that contains 2% to 5% lime by weight and chemical additives that improve the bond with dense, non-porous surfaces, such as concrete.
bond, bonded: An amount of money (usually between $5,000 and $10,000) that must be on deposit with a governmental agency in order to secure a contractor\’s license. The bond may be used to pay for the unpaid bills or disputed work of the contractor. (Not to be confused with a performance or surety bond, which is an insurance policy that guarantees proper completion of a project, and rarely used in residential construction.)
bonding: The permanent joining of metallic parts to form an electrically conductive path that ensures electrical continuity, and the capacity to safely conduct any fault current likely to be imposed.
bonding strip (electrical): A thin strip of metal inside armored or BX cable, which is meant to back up the primary ground.
boom: A truck used to hoist heavy material up and into place, such as to put trusses on a home or to set a heavy beam into place.
Boston ridge: A method of applying asphalt or wood shingles at the ridge or at the hips of a roof as a finish.
bottom chord: The lower or bottom horizontal member of a truss.
bottom plate: The 2x4s or 2x6s that lay on the subfloor upon which the vertical studs are installed. Also called asole plate.
bow: A curve, bend, warping or other deviation from flatness in glass or wood.
box cornice: A cornice completely closed with trim work.
brace: An inclined piece of framing lumber applied to a wall or floor to stifle the structure, often used on walls as temporary bracing until framing has been completed.
bracing: Ties and rods placed to support and strengthen various parts of a building; used for lateral stability for columns and beams.
brake metal: Sheet metal that has been bent to the desired configuration.
branch circuit: Wiring that runs from a service panel or sub-panel to outlets; the circuit conductors between the final over-current device protecting the circuit and the receptacle(s)/outlet(s). Branch circuits are protected by fuses or breakers at the panel.
breaker box: A metal box that contains circuit breakers or fuses that control the electrical current in a home.
breaker panel: The electrical box that distributes electric power entering the home to each branch circuit (each plug and switch) and composed of circuit breakers.
breezeway: A covered/roofed and closed- or open-sided passageway connecting two structures, such as a house and a garage.
brick ledge: Part of the foundation wall where brick veneer rests.
brick lintel: The metal angle iron that brick rests on, typically found above a window, door or other opening.
brick mold: Trim used around an exterior door jamb onto which siding butts.
brick tie: A small, corrugated metal strip (1×6 to 8 inches long) nailed to wall sheeting or studs that are inserted into the grout mortar joint of veneer brick to hold the veneer wall to the sheeted wall behind it.
brick veneer: A facing of brick laid against and fastened to the sheathing of a frame wall or tile wall construction.
bridging: Small wood or metal members that are inserted in a diagonal position between floor joists at midspan to act as both tension and compression members for the purpose of bracing the joists and spreading the action of loads.
broker: One who acts as an agent for others in the negotiation of contracts, purchases and/or sales in return for a fee or commission.
browncoat: The coat of plaster directly beneath the finish coat. In three-coat work, the browncoat is the second coat.
BTU: Acronym for British thermal unit, which is a measure of the capacity of a heating or cooling system; the amount of heat energy required to raise the temperature of 1 pound of water through a change of 1 degree.
bubbling: In glazing, open or closed pockets in a sealant caused by the release, production or expansion of gases.
buck: Often used in reference to rough-frame opening members. Door bucks are used in reference to a metal door frame.
buckling: The bending of a building material as a result of wear and tear or contact with a substance, such as water.
builder’s risk insurance: Insurance coverage on a construction project during construction, which may include extended coverage that can be added to the contract for the customer’s protection.
building: The primary building subject of an inspection.
building brick: Brick for building purposes not especially treated for texture or color, formerly called “common brick.” It is stronger than face brick.
building code: Minimum local and/or state regulations established to protect health and safety, which apply to building design, construction, rehabilitation, repair, materials, occupancy and use; community ordinances governing the manner in which a home may be constructed or modified.
building department: Local authority having jurisdiction over the construction, alteration and use of a property.
building envelope: The enclosure (exterior walls and roof) that defines the heated/cooled area of a building.
building paper: A general term for papers, felts and similar sheet materials used in buildings without reference to their properties or uses. Generally comes in long rolls.
building permit: Written authorization from the city, county or other governing regulatory body giving permission to construct or renovate a building. A building permit is specific to the building project described in the application.
building systems: Components, assemblies and systems that are a part of the overall building and property, such as pavement, flatwork, structural components, roofing, exterior walls, plumbing, HVAC, electrical components, fire prevention, etc.
built-in: Permanently installed.
built-up beam: Beam or girder created by sistering or scabbing two or more pieces of lumber together. Also called a build-up girder.
built-up roof, roofing (BUR): Generally used on flat or low-pitched roofs, a roofing system composed of three to five layers of asphalt felt laminated with coal tar, pitch or asphalt, and finished on top with crushed slag or gravel.
bullfloat: A large flat tool with a handle, usually made of wood, aluminum or magnesium, used to finish and flatten a slab. Also describes the first stage in the final finish of concrete to smooth and level hills and voids left after screeding; sometimes substituted for darbying.
bullnose drywall: Rounded drywall corners.
bundle: A package of shingles that contains three, four or five bundles per square.
BUR: See built-up roofing.
bushing: A pipe fitting for joining pipes having different diameters. A bushing is threaded on the inside and outside.
butt glazing: The installation of glass products where the vertical glass edges are without structural supporting mullions.
butt joint: The junction where the ends of two timbers or other members meet in a square-cut joint.
butterfly roof: A roof assembly that pitches sharply from either side toward the center.
buttering: In glazing, the application of sealant or compound to the flat surface of some member before placing the member in position, such as the buttering of a removable stop before fastening the stop in place.
butyl: A type of non-curing and non-skinning sealant made from butylene usually used for internal applications.
buy-down: A subsidy paid by a builder or developer to reduce monthly payments on a mortgage.
BX cable: Armored electrical cable wrapped in a galvanized-steel outer covering. A factory assembly of insulated conductors inside a flexible metallic covering. It can be run anywhere except where exposed to excessive moisture. It should not be run below grade. It must always be grounded and uses its armor as an equipment ground. It is difficult to pull out old wires or insert new ones.
bypass doors: Doors that slide by each other, commonly used as closet doors.