Glossary Terms for Marvin Infinity Windows

Marvin Infinity Windows descriptions and definitions of terms we use in the remodeling and replacement window industry.

ACRYLONITRILE BUTADIENE STYRENE (ABS): A composite plastic that is often used for building materials because of its heat and impact resistant properties.

APRON: A piece of casing or decorative trim installed against the wall immediately beneath the stool of a window.

ARGON GAS: An inert gas known for its ability to provide insulating properties in insulating glass air spaces.

ASTRAGAL: A moulding applied to one stile of a French door which the other door panel strikes. Usually head and footbolt devices will be found on the astragal side.

ASSEMBLY: A collection of single units mulled together.

AWNING WINDOW: A combination of frame and sash, hinged at the top of the vertical jambs which allows the unit to pivot from the top with the sash opening to the exterior of the building.

BALANCES: Any system of block and tackle or spiral springs used in the jamb of double hung units to counter the weight of the sash to allow for easier opening and top sash retention.

BAR: A narrow member in a divider system to create a series of divided lites in the daylight opening of the sash or panel. GBG and SDL spacer bars must be connected to the rails and stiles. Bars can be assembled into a variety of patterns including cottage, prairie, rectangular, etc.

BAY WINDOWS: An arrangement of three individual Marvin Infinity windows units, attached as to project from the building at various angles.

BOW WINDOWS: A series of adjoining window units, installed on a radius.

BRICK MOULD CASING (BMC): An exterior moulding that butts to the exterior facing material of the structure. The casing serves as the boundary moulding for brick or other siding material.

CAM LOCK: A lock used on casement and awning windows that utilizes a cam to pull the window closed.

CAPILLARY TUBES: A tube inserted into the insulating glass spacer that allows the inside and outside air pressure to equalize in higher elevations. Capillary tubes will allow gas fills, other than air to escape.

CASEMENT WINDOW (CA): A vertical hinged window system consisting of a frame, sash, weather strip, locks, hinges and an operating crank device, on operating units.

CELLULAR POLYVINYL CHLORIDE (cPVC): A wood replacement product made of Polyvinyl Chloride molded into forms enabling it to be cut and shaped much like wood without wood’s disadvantages.

CHECK RAIL: The horizontal members of a double hung sash that are designed to mate with the check rail of the paired sash.

CLEAR OPENING (CO): The opening created when the window or door is completely open.

CLUTCH: The plastic and metal assembly on which the cam pivots of a double hung sash rests. The clutch is attached to the balance system which allow opening and closing of the sash.

CONDENSATION RESISTANCE (CR): Measures the ability of a product to resist the formation of condensation on the interior surface of that product. The higher the CR rating the better it resists forming condensation.

COTTAGE WINDOW: A double hung window with the top sash smaller than the bottom sash.

DAYLIGHT OPENING (DLO): The width and the height of the visible glass.

DEPTH OF THE JAMB: The point from the backside of the nailing fins to the interior of the frame.

DESIGN PRESSURE (DP): A rating system that is based on testing for structural performance under static air pressure. Water leakage, air leakage, operating force and forced entry must also comply to attain a DP rating.

DIRECT GLAZE (DG): Refers to a stationary window where the glass is glazed directly into the frame.

DIVIDED LITES: See Simulated Divided Lites.

DOUBLE HUNG (DH): A window unit with two movable sash which operate by sliding vertically. Double hung sash are retained in position with the use of balancing devices.

DRIP CAP: A formed aluminum or vinyl piece which is installed at the top of windows and doors that allows water to run off the casing and head jamb of the unit and prevent water from flowing into the frame.

EGRESS: Refers to an escape opening in a room designated as a sleeping area. Windows and doors must meet a minimum size requirement to qualify as an egress product.

EMISSIVITY: A measure of a surface’s ability to emit long-wave infrared radiation or room temperature radiant heat energy. Emissivity varies from 0 (no emitted infrared) to 1 (100% emitted infrared). The lower the emissivity, the lower the resultant U-Factor and the better insulating performance of the material.

ESCUTCHEON: A decorative door handle plate attached to the stile directly behind the handle(s).

EVERWOOD™: Low-maintenance engineered interior wood grain surface that looks, feels, paints and stains like wood.

EXTRUSION: A linear component of plastic or metal made by the process of heating the raw material and forcing it through a die as it cools to provide a specific cross-sectional shape.

FENESTRATION: Anything designed to fill an opening in a structure. Used in our industry to specifically apply to doors and windows.

FIELD MEASUREMENT GUIDE: A form that is filled out prior to ordering the Infinity product to ensure the correct measurements are taken to ensure proper fit of the window.

FLUSH FIN: Exterior accessory for full frame units used to seal against the exterior of a building. Primarily used in stucco applications.

FOOTBOLT: A locking rod device installed vertically in the stile or astragal of a door, when activated, secures the panel in a stationary position.

FRAME: The stationary portion of Marvin Infinity Windows that enclose either the glass (direct glaze) or the sash (operating or stationary) and consists of the following parts:

  1. HEAD JAMB: The top frame member.
  2. SILL: The bottom frame member.
  3. SIDE JAMB: Side or vertical frame members.
  4. JAMB EXTENSION: The addition onto the standard jamb to adapt a window unit to deeper wall thicknesses. (Field installed)
  5. BRICK MOULD: The exterior trim member applied to the side jambs and head jamb. Often used to secure the wood windows to the wall opening.
  6. FLUSH FIN: Exterior accessory for full frame units used to seal against the exterior of a building. Primarily used in stucco applications.

FRAME EXPANDER: Decorative exterior accessory for full frame units used to seal against the exterior of a building. Primarily used in stucco applications.

FRENCH DOOR: A door consisting of moderate width top rail and stiles with a larger bottom rail.

GLASS SIZE (GS): The measurement of the actual glass, not the visible glass.

GLAZING: The action or process of installing glass into windows and doors.

GLIDER (GL): Horizontal operating units which have one or more sash that glide open and shut horizontally.

GRILLES-BETWEEN-THE-GLASS (GBG): A narrow profiled aluminum member installed between two pieces of glass that gives a divided-lite appearance in Marvin Infinity Windows.

HANDING: A term used to describe the right or left hand operation of a window or door. IG: Insulating glass

INACTIVE PANEL (X): Secondary operating door panel.

INSERT UNIT: A specially designed, made-to-order sash and frame unit that is used to replace existing window without disturbing existing interior trim or exterior casing.

INSWING FRENCH DOOR: A French door with panels that swing to the inside. One or two panel units available from Integrity by Marvin as stationary or operating.

INSULATING GLASS (IG): A glass assembly with two or more panes of glass sealed with a perimeter spacer.

JAMB EXTENSION: A jamb-like member usually surfaced on four sides, which increases or extends the depth of the exterior or interior window or door frame.

KEYED CYLINDER LOCK: A lock providing an exterior entry and locking convenience.

LAMINATED GLASS: Glass composed of two sheets of glass fused together with a sheet of transparent plastic between the sheets. When broken, laminated glass will generally not leave the opening and is often used as safety or security glazing.

Low E GLASS: Low E stands for low emissivity. The lower the emissivity the higher the percentage of long wave radiation blocked thereby improving thermal performance. Low E glass is coated with a thin microscopic, virtually invisible, metal or metallic oxide layer. The primary function is to reduce the U-factor by suppressing radiative heat flow. A secondary feature is the blocking of short wave radiation to impede heat gain. There are two basic types of Low E glass. The first, vacuum or sputter coated Low E, is referred to as softcoat (See Low E2 definition). The second is pyrolitic Low E commonly referred to as hardcoat. Low E1: Glass coating specific to cold weather performance. In direct exposure to the sun, it lets the winter sun’s heat into the home. Ideal for passive solar design.

Low E2: A high performance glass providing year-round comfort in all types of weather with Marvin Infinity Windows. It reflects heat back into the room in the winter and rejects the sun’s heat and damaging UV rays in the summer. The Low E2 coated glass products are specifically designed for insulating glass units as a second surface coating. I

Low E3: A high performance glass providing the highest levels of year-round comfort and energy savings. It provides the ideal balance of solar control and high visibility. Additionally, it provides a more efficient reduction in ultraviolet light transmission. Low ERS: A room side coating on a dual pane IG unit reflecting inside radiant heat back into the room.

Low E3/ERS: An advanced performance system of Low E3 and Low ERS coatings on dual pane insulating glass to maximize protection from heat loss and heat gain by enhancing the U-Factor of the window. Also provides maximized UV protection.

MASONRY OPENING (MO): A brick, stone or block opening into which a window or door unit is installed. Exterior casing may cause the Masonry Opening to be larger than the Rough Opening.

MEETING STILES: The vertical members of a glider sash or sliding door panel that are designed to mate with the meeting stile of the paired sash.

MULL COVER: Used as a cover for the mullion when joining two or more windows.

MULLING: The act of attaching two or more window or door units together. The joint is then finished with a mullion center cap or mull trim.

MULLION REINFORCEMENT (MRF): A system of high-strength members placed between units of an assembly and fastened to the frame of the units to provide enhanced structural performance.

MULTI-POINT LOCKING SYSTEM: A line of standard or optional multiple point locking mechanisms installed on the operative panel(s)/ sash of various Infinity products to enhance security and performance.

NON-KEYED LOCK: A handle without a keyed cylinder. The door cannot be locked or unlocked from the exterior

NAILING FIN: A factory installed vinyl strip that is inserted into a kerf in the frame of full frame units.

ORIEL WINDOW: A double hung window with the bottom sash smaller than the top sash.

OBSCURE GLASS: A pattern glass that provides privacy while maintaining full light transmission. It is formed by running molten glass through special rollers that apply the pattern to one side.

OUTSIDE MEASUREMENT (OM): The measurement in width from outside of jamb to outside of jamb. Height measurement from top of head jamb to bottom of sill. The outer edges of what is being measured.

ONE-WIDE (1W): Term used to describe one frame with single or multiple sash or panels.

OPERATOR (X): An operating sash, panel or unit.

OUTSWING FRENCH DOOR (OFD): A French door with panels that swing to the outside. One or two panel units available as stationary or operating.

OX and XO: The letters OX or XO identify the operation of window or door units as viewed from the exterior. The letter O stands for stationary while the letter X stands for operating.

PANEL: An assembly of stiles and rails with glass that form the stationary or operating section of the door and is fitted in the frame.

PERFORMANCE GRADE (PG): A numeric designator that defines performance that applies to: air leakage resistance, water penetration resistance and deflection resistance according to Standard Specifications.

PITCH: A term used to describe the angle of a roof. For example: A 4-12 pitch indicates that the roof rises 4″ (102) vertically for each 12″ (305) horizontally.

POLYGON (POLY): A high level term used to describe any shape with three or more straight sides. Typical fenestration shapes are triangles, trapezoids, pentagons, hexagons and octagons.

PULTRUSION: Lineal profiles of constant cross section manufactured by combining plastic resin and continuous glass fiber reinforcement for Marvin Infinity Windows. These thermally insulating and structural components are ideally suited for applications where strength, thermal stability and weather resistance are required.

RADIUS: The length of an imaginary line from the center point of a circle to the arc or circumference of a circle.

RAILS: The cross or horizontal members of the framework of a sash, door or other panel assembly.

ROTO-GEAR: A term used to describe the steel drive worm, gears and crank device used for opening awning and casement windows.

ROUGH OPENING (RO): The opening in the wall where a window or door unit is to be installed. Openings are larger than the size of the unit to allow room for insulation, shimming and squaring of the unit.

ROUND TOP (RT): Any window unit with a radius frame member. The most common shape is a semicircle window with a horizontal sill which may be mulled to the top of another window or door. Round tops can be used separately or combined with other units to create a seemingly endless selection.

SASH: An assembly of stiles and rails with glass that form the stationary or operating section of the window and is fitted into the frame. The operating and/or stationary portion of the window unit that is separate from the frame. The sash consists of two or more the following parts:

  1. STILES – Vertical sash members.
  2. RAILS – Horizontal sash members.
  3. CHECK RAILS – Horizontal sash members that meet, as in double hung units
  4. MEETING STILES – Vertical check stiles that meet, as in the glider or patio door.

SASH LIFT: A handle on the inside bottom rail of the lower sash for raising and lowering the sash.

SASH LOCK: A device which holds a window shut and prohibits it from being opened from the outside.

SCREEN OM (outside measurement): The width and the height of a screen including wood or metal surrounds.

SCREENS (full and half): A close-mesh woven screen material of metal or fiberglass attached to an aluminum surround. Screens inhibit entry of insects, yet permit light, air and vision.

SEQUENTIAL LOCKING SYSTEM: The action is sequential where the lower lock activates first moving the sash to the weather strip; the top then engages to snug the sash to the frame.

SILL: The horizontal member forming the bottom of a window or exterior door frame; the lowest member of the frame of a structure, resting on the foundation and supporting the frame.

SIMULATED DIVIDED LITES (SDL): Permanent grille bars adhered to the interior and exterior surfaces of the glass with a spacer bar between the panes of glass to simulate authentic divided lites.

SLIDING FRENCH DOOR (SFD): A sliding door utilizing French door style panels.

SLIDING PATIO DOOR (SPD): A sliding door utilizing narrow stiles and rails.

SNUBBER: An interlocking metal bracket attached at the center of the hinge side of a casement sash and frame with certain heights and top sides of an awning sash and frame with certain widths. It allows operation but pulls the sash tightly against the frame weather strip to maximize performance when closed.

SOLAR HEAT GAIN COEFFICIENT (SHGC): The ratio of the solar heat gain entering the space through the fenestration product to the incident solar radiation. Solar heat gain includes directly transmitted solar heat and absorbed solar radiation which is then reradiated, conducted, or convected into space. The lower a window’s SHGC, the less solar heat it transmits to the interior, and the greater its shading ability. SPACER: Used to separate the two pieces of glass in an insulating glass panel.

SQUARE FOOT (Sq. Ft.): For measuring the area of a unit. RO width (in inches) x RO height (in inches) divided by 144 equals the area in square feet of a unit.

STATIONARY (O): A non-operating sash, panel or unit.

STILES: The upright or vertical perimeter pieces of a sash, panel or screen.

STRUCTURAL BRACKET: Aluminum bracket used to attach a unit to the rough opening. It is used to add structural strength to an installation.

TEMPERED GLASS: Float glass panels heated and then cooled rapidly in a controlled environment. This process makes the glass several times stronger than regular glass. It also makes it safer because when broken it yields small pebble-like fragments.

THREE-WIDE (3W): Term referring to any product or unit when three frames (i.e. separate jambs) are mulled together as a multiple unit.

TRANSOM: A window above a Marvin Infinity Windows window or door.

TWO-WIDE (2W): Term referring to any product or unit when two frames (i.e. separate jambs) are mulled together as a multiple unit.

ULTREX: A pultruded composite material made of polyester resin and glass fibers with an acrylic cap on primary surfaces.

U-FACTOR: (Btu/hr.-sq. ft. – *F.) A measurement of the amount of heat flow through a product. The lower the U-factor, the greater the resistance to heat flow and better its insulating value.

UV BLOCKAGE: Low E glass options will screen out ultraviolet waves while allowing visible light into a structure, reducing fading damage to interior surfaces.

UNIT: One single product such as a one wide casement.

VENT OPENING: The total opening created when a door or window is completely open.

VISIBLE LIGHT TRANSMITTANCE (VT): Percentage of visible light transmitted through the unit.

WEATHER STRIP: A resilient material designed to seal the sash and frame members in order to reduce air and water infiltration.

WINDOW OPENING CONTROL DEVICE (WOCD): A device that limits the travel of sash with an emergency escape release mechanism.

XO: See OX entry.



Wrightway is the Marvin Infinity Windows dealer in the Oshkosh, Fond du Lac, and Appleton, WI territories. We have an expansive service area and we are experts in replacing siding, windows, and gutters and installing gutter guards. Replace your windows today and free up some of your time for more important things. Find out more at