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Below are terms related to homes and their systems and components. You may encounter these terms in your Home Inspection Report or when communicating with other inspectors or contractors about your home.

T - U

T-bar: A ribbed T-shaped bar with a flat metal plate at the bottom that is driven into the earth and used with chain link fence poles, and to mark the location of a water meter pit.


tab: The exposed portion of strip shingles defined by cutouts.


tail beam: A relatively short beam or joist supported in a wall on one end and by a header at the other.


tailpiece: The tubular part of a lavatory drain that runs from the drain flange to the trap.


taping: Applying joint tape over embedding compound in the process of joint treatment of drywall.


tear-off: In roofing, a term used to describe the complete removal of a built-up roof membrane and insulation, down to the exposed roof deck.


TECO clip: A metal strap that is nailed to secure roof rafters and trusses to the top horizontal wall plate. TECO stands for Timber Engineering Company, a U.K.-based company whose laboratories conduct physical testing and certification of timbers and similar building materials according to their use as defined by the IRC, IBC and ICC. Also called a hurricane clip.


tee (T): A T-shaped fitting with three openings.


tempered: Strengthened. Tempered glass will not shatter or create shards when broken, but will pelletize similar to an automobile window upon impact. Required in tub and shower enclosures, entry door glass and sidelight glass, and in windows where the window sill is less than 16 inches above the floor.


termite shield: A shield made of non-corroding metal that is placed in or on a foundation wall or other mass of masonry or around pipes to prevent the passage of termites.


termites: Insects that superficially resemble ants in size, general appearance, and habit of living in colonies. Subterranean termites establish themselves in buildings by entering from ground nests after a building has been constructed. If left alone, they will eat the woodwork, leaving a shell of sound wood to conceal their activities. Their damage may proceed so far as to cause collapse of parts of a structure before discovery. There are about 56 species of termites known in the United States. The two major ones, classified by the manner by which they attack wood, are ground-inhabiting or subterranean termites (the most common), and dry-wood termites, which are found almost exclusively along the extreme southern border and the Gulf of Mexico in the United States.


terneplate: Sheet iron or steel plated with an alloy of lead and tin and used as a roofing material.


terracotta: A ceramic material molded into masonry units and used for roofing tiles and flooring.


terrazzo tile: Named for the town in Italy, a composite material used for floor and wall treatments consisting of marble, quartz, granite, glass or other suitable chips, and poured in place with a binder or precast. The terrazzo is cured and then ground and polished to a smooth surface or otherwise finished to produce a uniformly textured surface.


texture paint: Paint that may be manipulated by a brush, trowel or other tool to produce various patterns.


thermal bridging: Insulation in between studs in a wall does not restrict the heat flow through those studs, and this heat flow is called thermal bridging. The overall R-value of that wall may be different from the R-value of the insulation itself.


thermal insulation: Any material high in resistance to heat transmission that, when placed inside walls, ceilings and floors of a structure, reduce the rate of heat flow.


thermal movement: The measured amount of dimensional change that a material exhibits as it is warmed or cooled.


thermal shock: The stress built up by sudden and measurable temperature changes that results in damage of a structural component or in different parts of the same component due to a thermal gradient.


Thermo-ply®: Exterior laminated sheathing nailed to the exterior side of exterior walls; measures 1/4-inch thick and comes in 4x8 and 4x10 sheets with an aluminumized surface.


thermopane window: A window composed of a double layer of glass positioned side by side with a thin strip of foam material that bonds the two layers of window glass together to form a storm-window design.


thermoplastic material: Solid material that becomes softened by increasing temperatures and hardened by decreasing temperatures.


thermostat: A device that relegates the temperature of a room or building by switching heating or cooling equipment on or off.


thermostatic valve: A mixing valve that automatically maintains the temperature setting by regulating fluctuations in water temperature at the water inlets and immediately adjusts the ratio of hot and cold water that is discharged by the valve.


thimble: The tube or lining through a wall that a connector passes through to enter a flue or that a flue passes through to exit a roof.


three-dimensional shingles: Shingles that have added dimensionality because of extra layers or tabs, giving them a shake-like appearance. Also called architectural shingles and laminated shingles.


three-phase: In electrical work, a wiring system consisting of four wires and used in industrial and commercial applications. This system is suitable for installations requiring large motors. It consists of three hot wires and one ground wire. The voltage in each hot wire is out of phase with the others by one-third of a cycle, as if produced by three different generators.


threshold: A strip of wood or metal with beveled edges used over the finish floor and the sill of exterior doors.


through-wall flashing: Flashing that extends completely through a masonry wall, designed and applied in combination with counter-flashings to prevent water that may enter the wall above from proceeding downward into the wall, the roof deck and the roofing system.


THW: A flame-retardant thermoplastic conductor that is moisture- and heat-resistant and can be used in wet and dry locations. The letters THW stand for thermoplastic, heat and wire.


tie-in: In roofing, a term used to describe the joining of a new roof with the old.


tilt-up wall: Pre-formed cast-concrete units that, when cured, are tilted to their vertical position and secured by mechanical fasteners to an erected structural steel.


timber: Yard lumber (including beams, stringers, posts, caps, sills girders and purlins) that is 5 inches or more in its least dimension.


tinted glass: Glass that has colorants added during manufacturing that give it color, as well as light- and heat-reducing capabilities. The color extends throughout the thickness of the glass.


tip-up: The downspout extension that directs water from the home's gutter system away from the foundation. It swings up out of the way to make room when mowing the lawn, etc.


Title 24: A set of U.S. federal laws that mandates the construction industry to conserve energy.


TJ (TJI): Manufactured truss joints resembling the letter I that are used as floor joists and rafters. I-joists include two key parts: flanges and webs. The flange may be made of laminated veneer lumber or dimensional lumber, usually formed into a width of 1-1/2 inches. The web is commonly made of plywood or oriented strand board (OSB). Large holes can be cut in the web to accommodate ductwork and plumbing waste lines. I-joists are available in lengths up to 60 inches long.


toe bead: Sealant applied at the intersection of the outboard glazing stop and the bottom of the glazing channel of a window. It must be sized to provide a seal to the edge of the glass.


toe-nailing: To drive a nail at a slant to the initial surface in order to permit it to penetrate into a second member.


toilet room: A room containing a water closet or urinal, but not a bathtub or shower.


tongue and groove (T&G): A type of flooring in which the tongue of one board is joined to the groove of another board.


tooling: Pressing in and striking a sealant in a joint to press the sealant against the sides of a joint and secure total adhesion; the finishing off of the surface of a sealant in a joint so that it is flush with the surface.


top chord: The upper or top member of a truss.


top plate: The top horizontal member of a frame wall.


top-mopping: The finished mopping of hot bitumen on a built-up roof.


top-mount faucet: A faucet that is held in place by nuts located underneath the sink. Also called a center-set faucet.


torch-down roof: A roofing material used primarily on flat roofs that comes in rolls and is applied to the roof with an open flame or torch. Also called a single-ply roof and modified-bitumen roof.


torching: Applying direct flame to a membrane for the purpose of melting, heating and/or adhering.


transmitter (garage door): The small push-button device that causes the garage door to open and close.


trap: A plumbing fitting that holds water and prevents air and gas from backing up into a fixture.


tread: A step; the horizontal board in a stairway on which the foot is placed.


treated lumber: A wood product that has been impregnated with chemicals that reduce damage from wood rot and/or insects. Often used for the portions of a structure that are likely to be in contact with soil and/or water. Such wood may also be treated with a fire retardant.


tree crown: The branches growing out from a tree, including twigs and foliage.


trim: (1) Interior trim: The finish materials inside a building, such as moldings applied around openings (window trim, door trim), and at the floors and ceilings of rooms (baseboard, cornice, and other moldings). Also, the physical work of installing interior doors and interior woodwork, to include all handrails, guardrails, stairway balustrades, mantles, light boxes, baseboards, door casings, cabinets, countertops, shelves, windowsills, aprons, etc. (2) Plumbing/Heating/Electrical trim: The work that the mechanical contractors perform to finish their work when the home is nearing completion and occupancy. (3) Exterior trim: The finish materials on the exterior of a building, such as moldings applied around openings (window trim, exterior door trim), siding, attic vents, crawlspace vents, shutters, etc. Also, the physical work of installing these materials.


trim kit: Refers to the outside decorative parts that conceal a faucet rough-in.


trimmer: A beam or joist to which a header is nailed in framing for a chimney, stairway or other opening.


triple-glazed window: The most energy-efficient type of window. Gases are sealed between three panes of glass and low-E coatings are applied on two of the panes. This can bring the energy efficiency up to a value of R-10 at the center area of the glass.


truss: A frame or jointed structure designed to act as a beam of long span, while each member is usually subjected to length-wise stress only (either tension or compression).


tub trap: A curved, U-shaped section of a bathtub drainpipe that holds a water seal to prevent sewer gases from entering the home through the tub's water drain.


tuck-pointing: The re-grouting of defective mortar joints in a masonry or brick wall.


turpentine: A volatile oil used as a thinner in paints and as a solvent in varnishes.


TW: Abbreviation for thermoplastic wire or conductor that can be used in dry or wet locations, has no outer covering, and is not heat-resistant but is moisture-resistant.


two-part sealant: A product composed of a base and curing agent or accelerator, necessarily packaged in two separate containers that are uniformly mixed just prior to use.




U-value: A measure of air-to-heat transmission (loss or gain) through a window due to the thermal conductance and the difference in indoor and outdoor temperatures. As the U-value decreases, so does the amount of heat that is transferred through the glazing material. The lower the U-value, the more restrictive the fenestration product is to heat transfer. Reciprocal of R-value.

ultraviolet (UV) degradation: A reduction in certain performance limits caused by exposure to ultraviolet light.


ultraviolet rays (UV rays): The invisible rays of the light spectrum that are at its violet end.


undercoat: A coating applied prior to the finishing or top coats of a paint job. It may be the first of two or three coats. Also called a priming coat.


undercounter: A style of lavatory that is positioned under the cutout of the countertop.


underground plumbing: The plumbing drain and waste lines that are installed beneath a basement floor.


underlayment: A material placed under finish coverings, such as flooring or shingles, that provides a smooth, even surface for applying the finish.


union: A plumbing fitting that joins pipes end-to-end so that they can be dismantled.


union nut: A fitting that joins two sections of pipe.


uprights: Vertical members that support the sides of a trench to prevent its collapse.

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