Glossary: P-T

Palladian: A large, arch-top window flanked by smaller windows on each side.

Panel: Component, usually wood, mounted within stile-and-rail members of doors; used to refer to the entire door.

Panning: In replacement window work, the outside aluminum trim that can extend around the perimeter of the window opening; used to cover up the old window material.

Pareto Principal: A management principle that breaks down complicated processes or tasks into the vital few and the trivial many.

Parting Stop: A narrow moulding, either integral or applied, that holds a sash or panel in position in a frame.

Passive Restraint System: A system of protection that requires no effort on the part of the occupants of a vehicle, i.e., self-retracting seat belts, airbags.

Pattern Cutters: Sometimes called rolled or rough rolled glass, patterned glass is one type of rolled glass having a pattern impressed on one or both sides. Used extensively for light control and decorative glazing.

Peel Test: A test of an adhesive or sealant using one rigid and one flexible substrate. The flexible material is folded back (usually 180°) and the substrates are peeled apart. Strength is measured in pounds per inch of width.

Permanent Set: Occurs when a sealant is stretched, released, and does not return to its original length, but remains longer.

Personal Protective Equipment (PPE): The safety gear worn by an auto glass repair technician. It includes nitrile gloves, safety or ultraviolet glasses, dust and mist mask (dual strap), first aid kit, and any additional equipment required by company policy.

Poly-Isobutylene Tape (PIB Tape): Used to form the primary seal of a dual seal insulating glass unit.

Picture Window: Large, non-operating window. It is usually longer than it is wide to provide a panoramic view.

Pigment: A coloring substance or matter.

Pinchweld: A type of metal weld joint. In the auto glass industry, the pinchweld is the part of the vehicle frame where the glass adheres.

Pit: The impact point from which, typically, a small piece of glass is missing.

Pivot Window: A unit with a sash that swings open or shut by revolving on pivots at either side of the sash or at top and bottom.

Plasticizer: A material which softens a sealant or adhesive by solvent action.

Plate Glass: Flat glass produced by grinding and polishing to create parallel plane surfaces affording excellent vision. Although the term is still used commonly, most window glass is now produced using the float process. See Float Glass.

Pneumatic: An air-powered power tool.

Pocket Window: A unit designed for replacement applications; is installed into the existing window frame after removal of the sash, balance hardware and parting stops. Also called an insert window, these units allow existing interior and exterior trim to be maintained.

Polishing Lubricant: A lubricant use to aid in polishing glass and plastics.

Polycarbonate: A plastic material used for glazing.

Polymer: A compound consisting of long chain-like molecules. The building units in the chain are monomers.

Polysulfide Rubber: A synthetic polymer usually obtained from sodium polysulfide. Polysulfide rubbers make very good sealants.

Polysulfide Sealants: Sealants that adhere well to glass, aluminum, and spacer and corner materials.

Polysulfide: An adhesive used to bond auto glass to vehicles prior to the advent of urethane.

Polyvinyl Butyral (PVB): Plastic material used as the interlayer in the construction of some types of laminated glass.

Preformed Gaskets: Glazing gaskets manufactured to window openings, usually made of rubber or urethane.

Preformed Sealant: A sealant which is pre-shaped by the manufacturer. Example

Pre-Hanger: A company that buys doors, framing, hardware, glass lites and other components, and prepares (or pre-hangs) the unit for installation.

Prep: A cleaner or a product that enhances an adhesive; usually applied to the glass prior to the primer.

Pressure Sensitive Adhesive: Adhesive which retains tack after release of the solvent, so that it can be bonded by simple hand pressure.

Prime Window: A primary window, as opposed to a storm or combination unit added on.

Primer: An undercoat or chemical applied to a surface to improve the adhesion, durability, and appearance of a topcoat or the bond of an adhesive. A product (chemical) used to prepare metal bonding areas and ensure a strong bond between the glass part and the adhesive.

Primerless Urethane: A type of urethane adhesive that requires no primer on the glass surface. Metal primers may be necessary.

Pro Dealer: A term used for building product dealers and/or distributors that cater to professional customers such as home builders and remodeling contractors.

Production Cutters: Mechanical cutters.

Projected Window: A window in which the sash opens on hinges or pivots. Refers to casements, awnings and hoppers.

Pultrusion: The process used to produce fiberglass composite profiles or components for the production of windows and doors. Term also is used generally to refer to the composite profiles or lineals cut and processed to make window and door components.

Pump Gun: A device used for pumping sealants and adhesives.

PVB: See Polyvinyl Butyral.

Polyvinylchloride (PVC): An extruded material used for window and door framing.

Pyrolytic Glass: A glass product that is coated, usually to provide low-emissivity or solar-control benefits, during the manufacturing process at the molten glass stage. Commonly referred to as a hard coat, this type of coating offers a surface that is generally as durable as an ordinary glass surface, and therefore requires no special handling and does not need to be used in an insulating glass unit. The other type of glass coating is a sputter-coat, which is applied in a secondary process. Sometimes referred to as a soft-coat, these types of coatings generally require some additional care in handling and fabrication and must be used within an insulating glass unit.

Quarter glass: Backside windows in a vehicle.

Radiation: The transfer of heat in the form of electromagnetic waves from one separate surface to another. Low-E glass is designed to reduce this type of heat transfer by reflecting electromagnetic waves.

Rail: Horizontal member of the framework of a window sash or door.

Reaction Injection Molding (RIM): A molding process using reactive chemicals.

Reflective Glass: Window glass coated to reflect visible light and solar radiation striking the surface of the glass.

Regulator: A manually or power-operated device that rolls the vehicle’s windows up and down.

Release Agent: A liquid solvent used to soften adhesives or sealants.

Resilience: A measure of energy stored and recovered during a loading cycle. It is expressed in percentage.

Resin Laminating: A process used to laminate curved glass and other specialized, limited batch applications.

Resin: A solid organic material, generally not soluble in water, that has little or no tendency to crystallize. Resin is optically matched to auto glass and used to fill breaks and cracks. A term commonly used within the industry that refers to the raw materials used by PVC extruders to produce vinyl window profiles. The word is also used to describe a liquid material that is used in the production of laminated glass.

Retainer: An item that holds steady a panel to a frame.

Reveal Molding: Chrome or plastic molding which fits over and covers the edges of the windshield and back glass.

Rolled Glass: Manufactured by pouring glass from the furnace into a series of rollers, then shaped to the desired thickness, annealed and cut to size.  There are two basic types, patterned glass and wired glass.

Roof Window: An operable unit similar to a skylight placed in the sloping surface of a roof.

Rough Opening: Framed opening in a wall into which a window or door unit is to be installed.

Round-Top: One of several terms used for a variety of window units with one or more curved frame members, often used over another window or door opening. Also referred to as arch-tops, circle-tops and circle-heads.

Rubber Blocks or Spacers: Small rubber blocks/spacers, used by some manufacturers, to separate the glass from the metal frame.

R-Value: Resistance to thermal transfer or heat flow. Higher R-value numbers indicate greater insulating value. R-value is frequently used by the insulation industry and is the reciprocal of U-factor, a value more generally used in the window industry.

Safety Glass: A general term used for a strengthened or reinforced glass that is less subject to breakage or splintering and less likely to cause injury if broken. Law requires glass in doors to be some type of safety glazing product, such as tempered or laminated glass.

Safety Glazing: See Tempered Glass.

Salvage Part: A part, removed from a vehicle being scrapped, that is intended to be used as a replacement part.

Sandblasting: Sand blown by compressed air for etching or decorating glass.

Sash Cord: Rope or chain in double-hung windows that attaches the sash to the counter balance.

Sash Lift: Protruding or recessed handle on the inside bottom rail of the lower sash on a double- or single-hung window.

Sash Stiffener: A reinforcement usually inserted into a sash profile prior to assembly; designed to increase the strength of the unit.

Sash Weights: Concealed cast-iron weights used to counterbalance the sash of older double-hung windows.

Sash: An assembly of stiles and rails (vertical and horizontal members) made into a frame for holding glass.

Sausage Packs: A type of packaging for adhesive materials. The material is packaged in an aluminum foil pack. When the material is forced out of the package, the foil is crushed, reducing the amount of disposable waste.

Score: The term used to describe a "cut" on the surface of a glass or mirror with a glass cutter.

Sealant: Any material used to seal joints or openings against the intrusion or passage of any foreign substance, such as water, gases, air or dirt.

Sealer: A surface coating generally applied to fill cracks, pores or voids in a surface.

Self-Cleaning Glass: Glass treated with a special coating. Currently, commercially available products feature a coating that uses the sun's UV rays to break down organic dirt through what is called a photocatalytic effect. The coating also provides a hydrophilic effect, which reduces the surface tension of water to cause it to sheet down the surface easily and wash away dirt.

Setting Block: A small piece of neoprene or other suitable material that positions the glass in the frame or opening. An automotive part on which the glass rests in place.

Shaded Glass: Laminated glass in which a dark color has been added to the top section of the inner vinyl layer to improve driver visibility in glare. The color typically becomes lighter as the tint travels down the glass.

Shading Coefficient (SC): A measure of a window's ability to transmit solar heat, relative to that ability for 1/8-inch clear glass. The lower a unit's shading coefficient, the less solar heat it transmits, and the greater its shading ability. It is being phased out in favor of the solar heat gain coefficient (SHGC).

Shard: A sharp piece or fragment of glass.

Shear Test: A method of deforming a sealed or bonded joint by forcing the substrates to slide over each other. Shear strength is reported in units of force per unit area (psi).

Sheet Glass: A transparent, flat glass found in older windows, now largely replaced by float glass.

Shelf life: The amount of time resin stays fresh without being used. If the material exceeds its shelf life, the resin might become unstable and unusable.

Shore Hardness: The measure of firmness of a compound by means of a Durometer Hardness Gauge. (Range of 20-25 is about the firmness of an art gum eraser. Range of 90 is about the firmness of a rubber shoe heel.)
Short Crack: A crack on the windshield of 6 inches (15.24 cm) or less. See Crack.

Shrinkage: The percentage weight loss under specified conditions.

Side-Lite: Passenger car side windows.

Sidelites: Narrow fixed units mulled or joined to operating door units to give a more open appearance.

Silicone: A chemical used as a lubricant or as a sealant with a wide variety of usage.

Sill Pan: A product placed under a window or door during the installation process that is designed for water drainage.

Sill: The main horizontal member forming the bottom of the frame of a window or door.

Simulated Divided Lites (SDLs): A type of grille or grid design that creates the appearance of a number of smaller panes of glass separated by muntins, but actually uses larger lites of glass with the muntins placed between and/or on the surfaces of the glass layers.

Single Glazing: Use of a single lite of glass in a window; generally not as energy efficient as insulating glass or other forms of double glazing.

Single Seal Units: IG unit manufactured with only one sealant.

Single-Hung: A window resembling a double-hung or vertically sliding window, with a fixed, non-operating top sash.

Single-Strength Glass: Glass with thickness between 0.085 and 0.100 inch.

Skin: A single piece of material used as the face of a door.

Skinned Over: The appearance of an adhesive when it has started to cure.

Slab: A term for a complete door panel that has not been prepared for installation into a frame.

Smart Window: Generic term, sometimes used for windows offering high energy efficiency or windows featuring switchable glass to control solar gain.

Soft-Coat Glass: A glass product that is coated in a secondary process known as sputter-coating, usually to offer low-emissivity or solar-control benefits. The term refers to the fact that these types of coatings generally require some additional care in handling and fabrication and must be used within an insulating glass unit. A hard-coat or pyrolytic glass is coated during the manufacturing process at the molten glass stage. This type of coating offers a surface that is generally as durable as an ordinary glass surface, and therefore requires no special handling and does not need to be used in an insulating glass unit.

Solar glass: Glass that either reflects or absorbs the ultraviolet and infrared rays from the sun.

Solar Heat Gain Coefficient (SHGC): A rating, which is now generally replacing shading coefficient, measuring a window's ability to transmit solar heat. It measures both the solar radiation which is directly transmitted, as well as the solar radiation absorbed by the glass and subsequently transmitted. The lower a unit's solar heat gain coefficient, the less solar heat it transmits, and the greater its shading ability. It is approximately equal to the shading coefficient divided by 1.15. It is expressed as a number without units between 0 and 1.

Solar-Control Glass: Glass produced with a coating or tint that absorbs or reflects solar energy, thereby reducing solar gain.

Solid-Core Door: Flush door produced with a solid material placed within the door skins.

Solvent: A liquid in which another substance can be dissolved.

Sound Transmission Class (STC): A rating measuring a window's acoustic properties or its ability to reduce sound transmission. An STC rating is determined by measuring the sound transmission over a selected range of sound frequencies. The higher the number, the less sound transmitted.

Spacers, Flat: Small blocks of composition, neoprene, etc., placed on each side of lites to center the lites in the channel and maintain uniform width of sealant beads. They prevent excessive sealant distortion.

Spandrel: Opaque glazing material, often used for non-visionary areas between floors of a building.

Suspended Particle Device (SPD): A type of switchable glazing that typically uses laminated glass construction with the interlayer material featuring "suspended particles" that align when the glass unit is charged to provide a clear view and scatter when there is no charge, changing the glazing to translucent.

Spectrally Selective Glass: A coated or tinted glazing with optical properties that are transparent to some wavelengths of energy and reflective to others. Typically, spectrally selective coatings are designed to allow high levels of visible light or daylight into a building and reflect short-wave and long-wave infrared radiation.

Splayed Window: Window unit set at an angle in a wall.

Splines: A term used to denote filler strips.

Sputter-Coating: A secondary manufacturing process in which a thin layer of materials, usually designed to offer low-emissivity or solar-control benefits, is applied to glass. Sputter-coatings are commonly referred to as soft-coats, as they generally require some additional care in handling and fabrication and must be used within an insulating glass unit. A hard-coat or pyrolytic glass is coated during the manufacturing process at the molten glass stage. This type of coating offers a surface that is generally as durable as an ordinary glass surface, and therefore requires no special handling and does not need to be used in an insulating glass unit.

Stained: See Decorative Glass.

Star Break: Damage to a windshield marked by various-sized cracks radiating from the central impact point.

Static Mixer: A tube-like nozzle with a uniquely shaped insert that mixes two adhesive component materials together before the adhesive is dispensed.

Stile: The main vertical frame members of a sash or door.

Stile-and-rail door: Traditional type of wood door constructed with vertical stiles and rails with openings filled with raised wood panels or glass.

Stoce: Unit of glass sheets that is transported and stored without benefit of a wood crate.

Stone Break: A break on the outer layer of a laminated windshield. Typical stone breaks are star breaks, bullseyes or combination breaks. Non-technical term for damage on laminated glass.

Stool: Interior trim piece sometimes used to extend a window sill and act as a narrow shelf.

Stop: A moulding used to hold, position or separate window or door parts. Also, the moulding or component on the inside of a window frame against which the window sash rests or closes. Also called a bead, side stop, window stop and parting stop.

Straightedge: A piece of material with a straight edge for testing straight lines and surfaces or drawing straight lines.

Straight-Jaw Glass Pliers: Glass pliers that have identical upper and lower jaws.

Stress Cracks: Cracks resulting from unusual forces acting on the glass body.

Substrate: A hard surface, such as glass or metal, to which a sealant or adhesive is bonded. It is used to test adhesive product strengths.

Super Window: A generic term for a window with a very low U-value. Typically, it incorporates multiple glazings, low-E coatings, gas fills and an insulating spacer.

Supplementary Conditions: Provisions or conditions of a contract that are not standardized or that are special in relation to a particular contract.

Tack, Tackiness: The stickiness of the surface of a sealant or adhesive.

Tape Glazing: Installing glass or products with butyl tape.

Tapping Ball: An added feature to a wheel cutter that is used to weaken the glass on the underside of the score line prior to breaking.

Tear Strength: The load required to tear apart a sealant specimen.

Tempered glass: A strong break-resistant type of safety glass that, if broken, shatters into small granular pieces. Glass heat-treated to withstand greater than normal forces on its surface.

Tempering: Strengthening glass with heat.

Tenon: A rectangular projection cut out of a piece of wood for insertion into a mortise.

Tensile Strength: Resistance of a material to a tensile force (a stretch). The cohesive strength of a material, expressed in psi.

Tension: The act of straining or stretching.

Thermal Break: A thermally insulating or low-conductance material used between interior and exterior aluminum (or other conductive materials) window and door components.

Thermal Movement: Movement and changes in a structure caused by temperature changes.

Thermal Stress: As glass heats, it expands.  The center portion of a lite gets hotter and expands at a greater rate than the edges. When this occurs it strains the edges, this is called thermal stress.

Thixotropic: Non-sagging. A material which maintains its shape unless agitated. A thixotropic sealant can be placed vertically in a joint and will maintain its shape without sagging during the curing process.

Tilt window: A single- or double-hung window whose operable sash can be tilted into a room to allow cleaning of the exterior surface on the inside.

Tin Side: Also called the non-air side, the surface of glass facing the molten tin within a float glass furnace.

Tinted Glass: Glass to which a small amount of color has been added consistently throughout the glass batch. The tinting reduces glare and absorbs heat.

Tooling: The pressing of a compound in and against the side of a joint to form good adhesion; also dressing of a joint's surface compound for good appearance.

Toxic: Poisonous or dangerous to humans if swallowed or inhaled, or by contact, possibly resulting in eye or skin irritation.

Toxicity: The level or poisonous or toxic effect of a material.

Translucent: Permitting light to come through but diffusing it so that objects on the other side appear vague, distorted or imperfect.

Transom: Window used over the top of a door or window, primarily for additional light and aesthetic value.

Transparent: Permitting light to come through without distortions so that objects on the other side can be seen clearly.

Trim Ring: Ring of molded plastic or bowed metal which covers the headliner and secures the sunroof to a vehicle.

Triple glazing: Use of three panes of glass or plastic with two airspaces between. Generally refers to a sealed insulating unit.

True divided lites (TDLs): Traditional window construction incorporating smaller panes of glass actually separated by muntins, rather than simulating such an appearance with larger lites of glass and a muntin grid or grille placed between or on the surfaces of the glass layers.

Turret Cutter: A cutter head with more than one cutting wheel.

Twist: A crack which occurs when the windshield is twisted, either by flexing in the vehicle frame or because of improper mounting. It can be helped along if the windshield has a nick in the edge.

Two-Part Adhesive/Urethane: A type of adhesive that has two component parts: Hardener and resin. In auto glass adhesives, there are two-part urethanes and two-part adhesives. Although they are different chemically, they do have similar performance characteristics.

Two-Step Distributor: An industry term for a wholesale company that buys building products from the manufacturer and sells them to lumberyards and home centers, which in turn sell to builders, contractors and homeowners. A wholesaler that buys building products from a manufacturer and sells them to builders, contractors and homeowners is referred to as a one-step distributor.