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AAMA American Architectural Manufactur-ers Association, a national trade association that establishes voluntary standards for the window, door, and skylight industry. Acrylic Thermoplastic glazing material. Air Spacer Component placed at the perimeter of an insulating glass unit to sepa-rate the two lites of glass. Annealed Glass Standard float glass. ANSI American National Standards Institute, a clearinghouse organization for all types of standards and product specifications. Arch-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 circle-heads, circle-tops, and round-tops.
Argon An inert, nontoxic gas used in insulating glass to reduce heat transfer. ASHRAE American Society of Heating, Refrigeration and Air Conditioning Engineers. A national association that establishes standards for building energy performance. ASTM International Formerly, the American Society for Testing and Materials, an organization that establishes material standards (including glass) and test methods. It has also produced a window installation standard. Astragal Center post between two swinging doors. Awning Window with sash swinging outward from bottom. Back Bedding Material or compound used to seal the glass to a window sash.
Balance Mechanical device (normally spring loaded) used in single and double hung windows as a means of counter balancing the weight of the sash during opening and closing. Bay A combination of window units which projects to the exterior. Usually features a large center unit with two flanking units at 30° or 45° angles to the wall. BETEC Building Environment and Thermal Envelope Council. Part of the National Institute of Building Sciences, an organization representing government and industry, BETEC is involved in communicating government policy and influencing standards development within the industry. Boca Building Officials and Code Administrators. One of the three model code groups in the U.S. that has now merged into the International Code Council. Bottom Rail The bottom horizontal member of a window sash or door panel. Bow A combination window which projects to the exterior. Usually features four or more window units in a radial or bow formation.
Box Bay A combination of window units which projects to the exterior. Usually features a large center unit with two flanking units at 90° angles to the wall.Breather Tube Tube placed through air spacer and seal of insulating glass which allows unit to accommodate changes in pressure between time and location of manufacture and time and location of installation, where it is sealed. Usually used to accommodate changes in altitude between plant and job site. Also referred to as capillary tube.Brickmould A type of external casing for windows and doors. Caming The metal used in the construction of decorative glass panels. Usually zinc or brass. It is also applied to single glass lites to create a decorative glass look. Capillary Tube Tube placed through air spacer and seal of insulating glass which allows unit to accommodate changes in pressure between time and location of manufacture and time and location of installation, where it is sealed. Usually used to accommodate changes in altitude between plant and job site. Also referred to as breather tube. Casement Window with sash cranking outward, to the right or left.
Casing Exposed moulding or profile around a window or door, on either the inside or outside, to cover the space between the window frame or door jamb and the wall.Caulking A compound for tilling joints and sealing cracks to prevent leakage of water and air.Cellular PVC Extruded polyvinyl chloride material used in window and door components and trim. Unlike rigid (or hollow) vinyl, it features a foam or cell-structure inside. It can often be nailed, sawn, and fabricated like wood. Cellulosic Composite Generally a material combining an organic material, such as wood fiber, extruded with a plastic. Check Rail The bottom rail on the upper sash and the upper rail of the lower sash of a double-hung window unit, where the lock is mounted. Also referred to as a meeting rail. Circle-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-heads, and round-tops.
Cladding Material placed on the exterior of wood frame and sash components to pro-vide ease of maintenance. Common cladding materials include vinyl and extruded or roll-formed aluminum.Clerestory A window in the upper part of a high-ceilinged room that admits light to the center of the room.Combination Door A screen or storm door used in combination with a primary door. Storm windows also are referred to as combination windows. Composite A term used for window or door components which consist of two or more materials, such as glass fibers or wood and plastic. The term also is used for win-dows and doors which combine two or more materials in the frame or sash con-struction, such as a product with a wood interior and a vinyl or aluminum exterior. Condensation Water vapor from the air deposited on any cold surface which has a temperature below the dew point. Some-times a problem on cold window glass or framing that is exposed to humid indoor air. Corner Cleaner Machine which removes the bead of excess material formed in weld-ing vinyl window corners.
Cottage Double-hung A window in which the top sash is shorter than the bottom sash.CRF Condensation Resistance Factor. A rat-ing of a window's ability to resist condensa-tion. The higher the CRF, the less likely con-densation is to occur.Dade County Florida County, including Miami, which has set numerous standards and requirements for hurricane-resistant windows and doors. Desiccant A material used to absorb mois-ture from within the sealed airspace of an insulating glass unit. Design Pressure (DP)A measurement of the structural performance of a window or door. Usually specified as one-and-half times greater than necessary based on expected building wind and weather conditions. Divided LitesSeparately framed pieces or panes of glass. A double-hung window, for instance, often has several lites divided by muntins in each sash. These designs are often referred to as six-over-six, eight-over--one, etc., to indicate the number of lites in each sash. Designs simulating the appear-ance of separately-framed panes of glass are often referred to as SDLs or simulated divided lites. Designs using actual separate pieces of glass are sometimes referred to as TDL's or true divided lites.
DormerAn area which protrudes from the roof of a house, generally featuring one or more windows.Double GlazingUse of two panes of glass in a window to increase energy efficiency and provide other performance benefits. May or may not refer to an insulating glass unit.Double Hung WindowWindow featuring two operable sash which move vertically in the frame. Double Strength GlassGlass between 0.115 and 0.133 inches thick. Drip CapMoulding placed on top of the header brickmould or casing of a window frame. Edge EffectHeat transfer at the edge of an insulating glass unit due to the thermal properties of spacers and sealants.
Egress WindowWindow designed to be large enough for a fire fighter to climb in or a person to climb out in an emergency. U.S. building codes require each bedroom of a home to have an emergency exit window, with minimum sizes specified.Electrochromic GlazingGlass or other glazing material that can be switched from clear to opaque electronically.Energy StarA program sponsored by the U.S. Department of Energy which estab-lishes minimum performance standards for windows to be recognized as energy effi-cient. Four different sets of standards for U- value and solar heat gain have been estab-lished for four different climate zones in the US. Euro WindoorA consortium of European window, door, and curtainwall industry asso-ciations involved in the development of common EU standards. Extension JambA board or trim compo-nent which extends from the interior of the window frame to the interior wall. It is used to increase the depth of the jambs of a win-dow to fit a wall of any given thickness. ExtrusionThe process, in which a heated material is forced through a die, used to produce aluminum, vinyl (PVC), and other profiles or components used in the produc-tion of windows and doors. Term also is used to refer to the profiles or lineals manu-factured by this process and used to make window and door components.
FanlightA half-circle window over a door or window with radiating bars.FenestrationOriginally, an architectural term for the arrangement of windows, doors, and other glazed areas in a wall. Has evolved to become a standard industry term for windows, doors, skylights, and other glazed building openings. From the Latin word, "fenestra," meaning windowFinger-JointA toothed joint used to com-bine two pieces of wood end-to-end. Fixed LiteNon-venting or non-operable window. Fixed PanelNon-operable door usually combined with operable door unit. FlashingA strip of material that diverts water away from a window, door or skylight.
Float GlassGlass produced by a process in which the ribbon is floated across a bath of molten tin. The vast majority of flat glass is now produced using this method. The terms "plate" glass and "sheet" glass refer to older manufacturing methods still in limited use.Flush DoorDoor produced using two skins or faces separated by a stile-and-rail frame construction at the perimeter. Flush doors may be produced with a hollow core or solid core.FoggingA deposit or film left on an inte-rior surface of a sealed insulating glass unit due to extreme conditions or failed seals. French DoorGenerally refers to a pair of hinged doors which open from the middle. Also incorporates wider stile and rail com-ponents around the glass than typical glazed doors. Friction-weldA. process that uses high speed vibrations to join materials together. Fusion-weldA term used for a type of cor-ner construction, used with vinyl and other types of windows and doors, in which a small amount of material on the ends of two pieces are melted or softened, then pushed together to form a single piece. This also is referred to simply as a welded corner.
GlazingGlass (and other materials) in a window or door. Also, the act or process of fitting a unit with glass.Glazing StopA component of the sash or door panel which holds the glass in place.GliderA window with a movable sash that slides horizontally. Also, referred to as a hor-izontal sliding window. Green BuildingA movement in architectural and building circles aimed at creating structures that are occupant and environmentally friendly. Criteria such as sustain-ability, energy efficiency and healthfulness are considered. Green StrengthThe immediate holding power achieved by a sealant or adhesive. GrilleA term referring to window pane dividers or muntins. It may be a type of assembly fitted to the interior of the win-dow or door unit which can be detached for cleaning. Also, it can be fitted inside the sealed insulating glass unit, when it also is referred to as a grid.
Hard-Coat GlassA glass product that is coated during the manufacturing process at the molten glass stage. Also known as a pyrolytic coating, 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.HeadMain horizontal frame member at the top of a window or door.HeaderHorizontal framing member placed over the rough opening of a window or door to prevent the weight of wall or roof from resting on the frame. It is also known as a lintel. Heat GainThe transfer of heat from out-side to inside by means of conduction, con-vection, and radiation through all surfaces of a house. Heat LossThe transfer of heat from inside to outside by means of conduction, convection, and radiation through all surfaces of a house. Hollow-Core DoorFlush door con-structed with two skins or door faces sepa-rated by stiles and rails at the perimeter. Generally a honeycomb type support is used inside the door between the two faces.
HopperWindow with sash that swings inward from the top.Horizontal SliderA window with a movable sash that slides horizontally. It is also referred to as a gliding window.IBCInternational Building Code. Pub-lished by the International Code Council, the IBC primarily covers nonresidential construction. ICBOInternational Council of Building Officials. One of the three model code groups in the U.S. that has merged to form the International Code Council. IECCInternational Energy Conservation Code. Published by the International Code Council, the IECC sets forth compliance methods for energy-efficient construction of both residential and nonresidential con-struction. Insulating Glass (IG)Two or more lites of glass with a hermetically-sealed airspace be-tween the lites. The sealed space may con-tain air or be filed with an inert gas, such as argon.
Integrated SashA sash unit in which the insulating glass spacer profiles are inte-grated into the sash profiles. Separate IG construction is eliminated as the two lites of glass are applied and sealed directly to the sash, creating one assembly.IRCInternational Residential Code. Pub-lished by the International Code Council, the IRC primarily covers low-rise residential construction.J-ChannelInstalled or built-in to the side of a window or door, this channel is designed to accommodate the ends of sid-ing pieces to provide a finished appearance. JalousieWindow made up of horizontally mounted glass louvers or slats that abut each other tightly when closed and rotate outward when cranked open. JambMain vertical members forming the sides of a window or door frame. Jamb DepthWidth of a window or door from the interior to the exterior of the frame.
Jamb LinerThe track installed inside the jambs of a double-hung window on which the window sash slide.KD (Knocked Down)Unassembled window or door.Laminated GlassTwo or more sheets of glass with an inner layer of transparent plastic to which the glass adheres if broken. Used for enhanced safety and security, as well as sound reduction. Lean ManufacturingA business philosophy and / or strategy that focuses on eliminating waste, which includes all steps or processes that do not add value to the final product or service. It is usually employed along with the concept of continuous improvement. Leed Rating SystemA "green building" rating system established by the U.S. Green Building Council. Currently applicable to new commercial construction and major renovations, the program is being expanded to include residential construction as well. LEED stands for Leadership in Energy and Environmental Design. LintelA structural component or beam above a window or door opening that supports the wall above. It is also referred to as a header.
LiteA piece of glass. In windows and doors, refers to separately framed panes of glass (as well as designs simulating the look of separately framed pieces of glass). Sometimes spelled "light."Low Emissivity (Low-E) GlassA coated glass product which reflects heat.Masonry OpeningArea in a masonry wall left open for windows or door. MDFMedium-density fiberboard. A wood -fiber composite used in a variety of window, door, and millwork applications. MECModel Energy Code, established by Energy Policy Act of 1992 to serve as base-line for state energy codes. Although refer-enced in many state codes, it has been suc-ceeded by International Energy Conservation Code (IECC). Mechanical WindowA term for a product, usually vinyl, in which the corners are assembled using screws or other fastening mechanisms, as opposed to a welded corner construction. Also referred to as a mechanically fastened window.
MullionA component used to structurally join two window or door units.Multipoint LockA locking system, operated with one handle, which secures a window or door at two or more locking points.MuntinProfile or moulding, either vertical or horizontal, used to separate glass in a sash into multiple lites. Generally refers to components used to construct divided lite grids or grilles simulating a divided lite look. Nailing PinAn accessory component or integral extension of a window or patio door frame which generally laps over the conventional stud construction and through which nails are driven to secure the frame in place. NFRCNational Fenestration Rating Council. A body which has established methods for rating and certifying the energy performance of windows. NSDJANational Sash and Door Jobbers Association. Trade organization of window, door and millwork distributors. It is now the Association of Millwork Distributors (AMD).
NWWDANational Wood Window and Door Association. Trade organization which has established many standards related to wood window and door products. It is now the Window and Door Manufacturers Associa-tion (WDMA).One-Step DistributorAn industry term for a wholesale company which buys building products from a manufacturer and sells them to builders, contractors, and homeowners is referred to as a one-step distributor. A wholesaler which buys building products from the manufacturer and sells them to lumberyards and home centers, which in turn sell to builders, contractors, and home owners is referred to as a two-step distributor.OrielWindow style in which the upper sash is larger than the lower sash. PalladianA large, arch-top window flanked by smaller windows on each side. PanelComponent, usually wood, mounted within stile and rail members of doors. Also used to refer to the entire door. PanningIn 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.
Parting StopA narrow moulding, either integral or applied, that holds a sash or panel in position in a frame.Picture WindowLarge, non-operating window. It is usually longer than it is wide to provide a panoramic view.Pivot WindowA unit with a sash that swings open or shut by revolving on pivots at either side of the sash or at top and bottom. Plate GlassFlat 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. PolycarbonateA plastic material used for glazing. Polyvinyl Butyral (PVB)Plastic material used as the interlayer in the construction of some types of laminated glass.
Pre-HangerA company which buys doors, framing, hardware, glass lites, and other components, and prepares (or pre-hangs) the unit for installation.Prime WindowA primary window, as opposed to a storm or combination unit added on.Pro DealerA term used for building product dealers and/or distributors that cater to professional customers such as home builders and remodeling contractors. Projected WindowA window in which the sash opens on hinges or pivots. Refers to casements, awnings, and hoppers. PultrusionThe process used to produce fiberglass composite profiles or components used 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. PVCPolyvinylchloride. An extruded material used for window and door framing.
Pyrolytic GlassA glass product that is coated, usually to provide low-emissivity or solar control benefits, during the manufac-turing process at the molten glass stage. Commonly referred to as a hard coat, this type of coating offers a surface that is gener-ally as durable as an ordinary glass surface, and therefore requires no special handling and does not need to be used in an insulat-ing glass unit. The other type of glass coat-ing is a sputter-coat, which is applied in a secondary process. Sometimes referred to as a soft-coat, these types of coatings gener-ally require some additional care in handling and fabrication and must be used within an insulating glass unit.R-ValueResistance to thermal transferor heat flow. Higher R-value numbers indicate greater insulating value. R-value is fre-quently used by the insulation industry and is the reciprocal of U-value, a value more generally used in the window industry.RadiationThe 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. RailHorizontal member of the framework of a window sash or door. Reflective GlassWindow glass coated to reflect visible light and solar radiation strik-ing the surface of the glass. ResfenA computer program designed to calculate energy use based on window selection in residential buildings. Created under sponsorship of the U.S. Department of Energy by Lawrence Berkeley Laboratory (www.lbl.gov).
RFRadio frequency technology used with bar code scanners and other input devices in plant and warehouse tracking systems.Roof WindowAn operable unit similar to a skylight placed in the sloping surface of a roof.Rough OpeningFramed opening in a wail into which a window or door unit is to be installed. Round-TopOne 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. They are also referred to as arch-tops, circle-tops, and circle-heads. Safety GlassA strengthened or reinforced glass that is less subject to breakage or splin-tering and less likely to cause injury if bro-ken. Law requires glass in doors to be some type of safety glazing product, such as tem-pered or laminated glass. SashAn assembly of stiles and rails (verti-cal and horizontal members) made into a frame for holding glass.
Sash CordRope or chain in double-hung windows which attaches the sash to the counter balance.Sash LiftProtruding or recessed handle on the inside bottom rail of the lower sash on a double- or single-hung window.Sash WeightsConcealed cast-iron weights listed to counterbalance the sash of older double-hung windows. SBCCLSouthern Building Code Congress International One of the three model code groups in the U.S. that merged to form the International Code Council. Self-Cleaning GlassGlass 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 photo--catalytic effect. The coating also provides a hydrophilic effect, which reduces the sur-face tension of water to cause it to sheet down the surface easily and wash away dirt. Shading Coefficient (SC)A measure of a window's ability to transmit solar heat, rela-tive 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).
Sheet GlassA transparent, flat glass found in older windows, now largely replaced by float glass.Side LitesNarrow fixed units mulled or joined to operating door units to give a more open appearance.SillThe 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 GlazingUse of single lite of glass in a window. Generally not as energy efficient as insulating glass or other forms of double glazing. Single HungA window resembling a double-hung or vertically sliding window, with a fixed top sash.
Single Strength GlassGlass with thick-ness between 0.085 and 0.100 inches.SkinA single piece of material used as the face of a door.SlabA term for a complete door panel that has not been prepared for installation into a frame. Smart WindowGeneric term, sometimes used for windows offering high energy effi-ciency or windows featuring switch able glass to control solar gain. Soft-Coat GlassA glass product that is coated in a secondary process known as sputter-coating, usually to offer low-emissiv-ity or solar control benefits. The term refers to the fact that these types of coatings gen-erally require some additional care in han-dling and fabrication and must be used within an insulating glass unit. A hard-coat or pyrolytic glass is coated during the manu-facturing process at the molten glass stage. This type of coating offers a surface that is generally as durable as an ordinary glass sur-face, and therefore requires no special han-dling and does not need to be used in an insulating glass unit. Solar Control GlassGlass produced with a coating or tint that absorbs or reflects solar energy, thereby reducing solar gain.
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 trans-mits, and the greater is its shading ability. It is approximately equal to the shading coeffi-cient divided by 1.15. It is expressed as a number without units between 0 and 1.Solid-Core DoorFlush door produced with a solid material placed within the door skins.Sound Transmission Glass (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. Spectrally-Selective GlassA coated or tinted glazing with optical properties that is 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 WindowWindow unit set at an angle in a wall. Sputter-CoatingA secondary manufactur-ing process in which a thin layer of materi-als, 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.
StileThe main vertical frame members of a sash or door.Stile-And-Rail DoorTraditional type of wood door constructed with vertical stiles and rails with openings filled with raised wood panels or glass.StoolInterior trim piece sometime used to extend a window sill and act as a narrow shelf. StopA 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. Super WindowA generic term for a win-dow with a very low U-value. Typically, it incorporates multiple glazings, low-E coat-ings, gas fills, and an insulating spacer. Tempered GlassGlass heat treated to withstand greater than normal forces on its surface. When it breaks, it shatters into small pieces to reduce hazard.
TenonA rectangular projection cut out of a piece of wood for insertion into a mortise.Thermal BreakA thermally insulating or low-conductance material used between interior and exterior aluminum (or other conductive material) window and door components.Tilt WindowA single- or double-hung window whose operable sash can be tilted into a room to allow cleaning of the exterior sur-face on the inside. TransomWindow used over the top of a door or window, primarily for additional light and aesthetic value. Triple GlazingUse of three panes of glass or plastic with two airspaces between. Gen-erally refers to a scaled 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.
Two-Step DistributorAn industry term for a wholesale company which buys build-ing products from the manufacturer and sells them to lumberyards and home cen-ters, which in turn sell to builders, contrac-tors, and homeowners. A wholesaler, which buys building products from a manufacturer and sells them to builders, contractors, and homeowners, is referred to as a one-step distributor.U-FactorRate of heat flow-value through a building component, from room air to outside air. Also referred to as U-value. The lower the U-factor, the better the insulating value. U-factor, a rating more generally used in the window industry, is the reciprocal of R-value, a rating commonly used in the insulation industry.Ultraviolet Light (UV)Invisible rays of solar radiation at the shortwavelength violet end of the spectrum. Ultraviolet rays can cause fading of paint finishes, carpets, and fabrics, as well as deterioration of some materials. VinylGeneric term for polyvinylchloride or PVC, an extruded material used for window and door framing. WarmedgeA type of insulating glass construction using an airspace offering lower thermal conductance than traditional aluminum spacer. Warmedge IG units typically offer higher resistance to condensation and an incremental improvement in window energy performance. WDMAWindow and Door Manufacturers Association. Formerly the National Wood Window and Door Association, this trade organization has established many standards related to wood window and door products.
WeatherstrippingA material or device used to seal the openings, gaps, or cracks of venting window and door units to prevent water and air infiltration.Weep HoleA small opening in window or sill member through which water may drain to the building exterior.Weld A term used for a type of corner construction, used with vinyl and other types of windows and doors, in which a small amount of material at the two pieces are melted or softened, then pushed together to form a single piece. This also is referred to commonly as a fusionweld. Wildland/Urban InterfaceAn area where buildings are bounded by wild or natural areas, which are a particular concern in regions where wild fires are a concern. Some fire and code officials are looking at the establishment of fire resistance requirements for exterior building products in these "interface" areas. WindloadForce exerted on a surface by moving air.