Buyer's Guide

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CUSTOM SIZING

Windows custom built to fit any size opening are often needed for specific requirements in new construction. This can also reduce costs for preparing and finishing of replacement windows.

Window Terms Glossary

CONFUSED BY ALL THE TECHNICAL WINDOW TERMS? U. S. Window Factory has taken these confusing technical terms and made them easier to understand.

 

  • A, B, C
  • D,E F
  • G,H,I
  • J, K, L
  • M, N, O
  • P,Q, R
  • S,T,U
  • V, W

M

  • Main Frame - The head, sill and jambs sections of a window.
  • Masonry Opening – The opening in a masonry wall to accept a window or door unit, the same as a rough opening in a frame wall.  
  • Mechanically Fastened Frame / Sash - Refers to frames or sash fastened with screws.
  • Meeting Rail - The horizontal sections of a pair of sash that meet when the sash are closed.
  • Meeting Stile – The vertical member in a pair of stiles, as in abutting casement windows.
  • Miter – Molding returned upon itself at right angles. In joinery the ends of two pieces that are cut at a 45 degree angle abutting upon one another so as to form a right angle.
  • Mullion - A vertical or horizontal connecting unit between two or more windows.

N

  • Nailing Fin - An extrusion that attaches to the window frame and used to secure the unit to the rough opening. (See Installation Fin)
  • National Fenestration Rating Counsel (NFRC) – Organization, which develops procedures for rating the energy performance of windows.
  • Night Latch - Latch mechanism on the inside of the top sash that retains the window in a partially open position for ventilation.  

O

  • Obscure Glass - Glass that has been made translucent instead of transparent. Used when privacy is an issue such as bathrooms.
  • Operable Window – Window, which can be opened for ventilation.
  • Operator – Crank-operated device for opening and closing casement or Jalousie windows.
  • Oriel Style Window (See Cottage) - A window with the meeting rail located off center of the frame.
  • Outside Casing – Trim or molding around a window or door on the exterior of the house. Casing usually refers to a flat board trim, typically 3” to 4” in width.

P

  • Pane – A Sheet of glass for glazing a window. After installation the pane is referred to as a lite.
  • Parting Bead – A vertical strip on each jamb that separates the sashes of a double hung window. (See Blind stop)
  • Patio door - A glass door that slides back and forth on adjustable tandem rollers. Available in 2 or 3 lite configurations with the operable panel available in any position.
  • Picture Window - A window that does not have a moveable sash.
  • Pocket Sill – A deep sill (frame) design that completely surrounds the bottom edge of the sash in the closed position.
  • Projected Window – An awning type window that swings either inward or outward at the top or bottom.
  • Push Bar – Used on an awning and other projecting sash windows for opening and closing instead of a crank operator.
  • PVC (Polyvinylchloride) – An extruded or molded plastic material used for window framing and as a thermal barrier for aluminum windows.

Q

  • Quarter Round Window – Stationary or operating window with glass shaped as a quarter circles; it is often divided into separate panes by a removable grille, installed on the interior or grille between the glasses.

R

  • R-value - Resistance a material has to heat flow. The higher the R-value, the greater the resistance.
  • Radiation - Wave energy transmitted directly from one object to another through the atmosphere or through transparent or translucent materials. The energy radiated is transmitted, absorbed, reflected or a combination of all three.
  • Rail – Horizontal members of a window sash or door panel.
  • Raised Exterior - An angled extension from the frame that adds an aesthetically pleasing dimension to the exterior of the window.
  • Resin Art Glass - A look of stained glass is handcrafted directly onto the glass during the manufacturing process. 
  • Rough Opening – The opening left in a frame wall to receive a window or a door unit. The jack studs on each side, which supports the header across the top, form it. Cripples support the rough sill at the bottom. The rough opening generally allows 1/2” or more in each dimension in excess of the window or door unit dimension. Openings in brick walls are known as masonry openings.
  • Rough Sill – The horizontal rough framing member, usually 2 X 4, which forms the bottom of the rough opening.

S

  • SafeGard® glass - Two panes of glass are bonded to a durable plastic interlayer, providing increased safety, UV protection and noise reduction. If a window gets broken the glass will adhere to the plastic interlayer - preventing glass fallout in the home.
  • Safety Glass – A strengthened or reinforced glass that is less subject to breakage or splintering, such as glass for storm doors and some windows.
  • Sash - The part of the window which contains the glass.
  • Sash Balance – A device for counter balancing a sash of a double hung window to hold it in an up position. There are four basic types:
    • Block & Tackle - A type of balance that employs a block and tackle apparatus and coiled spring. This type balance allows the sash to be easily removed from the window frame. A block and tackle balance can normally carry a heavier load than a spiral or friction balance.
    • Spiral – A balance using a spirally-wound spring.
    • Spring – A balance using a spring for counter-balancing; introduced in the 1980’s.
    • Constant Force – A coiled steel tape under spring tension for balancing the sash, located in the head jamb of the window frame.
    • Counterweight – The most common type of balancing system in older homes, utilizing a weight held by a sash rope or chain over a pulley.
  • Sash Cord – In older windows, the rope used to connect the sash with its counter weights.
  • Sash Crack – The opening between the operating sash and the frame of the window. Its thickness or measurement is equal to ½ the difference between the inside window frame dimension and the outside sash width. Crack foot length is used in calculating total air infiltration on a window unit.
  • Sash Lift- A handle for raising the lower sash.
  • Sash Lock – Generally a cam-action type lock applied to the rails of a window or at the open edges of a projecting window to pull rails tightly together or to seal the sash tightly to the frame, both for security and weather tightness.
  • Sash Stop – A molding that covers the joint between window sash and the jamb. Often limits sash travel.
  • Screen-Wire Cloth – A close-mesh woven screening material of metal, plastic or fiberglass for a window screen, to block the entry of insects but permit light, air and vision through the screen.
  • Sealant – A compressible plastic material used to seal any opening or junction of two parts, such as between the glass and its sash, commonly made of silicone, butyl tape or polysulfide.
  • Seal Failure (Hermetic Seal Failure) – The failure of the seal or seals in an insulated glass lite. Evidence of seal failure is usually dirt, dust or the appearance of water vapor within the insulated glass unit.
  • Seat Board – A flat board cut to fit the contour of a bow or bay window and installed between the sill and the flat wall surface, providing a seat of shelf space.
  • Shading Coefficient - The ratio of solar heat that is transferred through a glazing material relative to the solar heat transferred through 1/8" clear glass. The lower the number the more efficient the window is at reducing solar heat gains.
  • Shims – Wood wedges (often wood shingles) used to position on the window or door unit in a rough or masonry opening in a square, level and plumb position during (and after) installation.
  • Side Jamb – The upright vertical member forming the sides of the frame of a window or door unit.
  • Side Lite – A fixed often narrow glass window next to a door opening (or window).
  • Sill - The horizontal, bottom section of the main frame.
  • Sill Course – The row of bricks, cement blocks or stones laid across the bottom of a masonry opening which lie under the outside edges of the window sill.
  • Single Hung - A window in which one sash slides vertically and the other sash is fixed.
  • Single-Strength Glass - Glass with a thickness of approximately 3/32" (2.5 mm).
  • Sliding Sash – A window, this moves horizontally usually in grooves or tracks.
  • Slider Window - A window in which the sash move horizontally. Sliders are available in a 2- or 3-lite configuration, with the 3-lite having operable end vents.
  • Sloped Sill - The sill of the window that has a downward slope to the outside. This sill has sufficient degree of slope to aid in water runoff.
  • Snap-In-Grid – Wood or plastic removable divided-lites for sash and windows.
  • Solar Energy – Thermal radiation from the sun, as measured by short radiation wavelengths.
  • Solar Heat Gain - The percentage of heat gained from both direct sunlight and absorbed heat. The smaller the number, the greater the ability to reduce solar heat gain.
  • Spacer - Material placed between two or more pieces of glass in order to maintain a uniform width between the glass, and prevent sealant distortion.
  • Spline – For screening, a small strip of metal or flexible tubing or gasket material that fits into a groove in the screen frame to secure the screen cloth.
  • Stacked Window Units – A vertical grouping of an awning, hopper, casement, or non-operating windows to form a large, multiple units.
  • Stationary Sash – A fixed sash; also refereed to as a picture, studio vista or view sash.
  • Stepped Sloped Sill - An exclusive, sloped sill design with a defined step to aid in the prevention of air and/or water.
  • Stile – The upright or vertical outside members of a window (sash) or door panel, blind, screen or shutter.
  • Stool – The inside horizontal trims member at the bottom of the window from which rests on the sill. The shelf likes part that projects into the room. This is a common inside trim method used on wood double hung windows and sometimes called inside sill.
  • Stop – A trim member attached to the window frame to stop the same of a projecting window when closed to prevent it from swinging through the opening. It also covers the perimeter crack between the sash and the window frame in double hung and sliding windows and prevents sash from coming out of the frame. Stops used at the top and bottom of the balance channel prevent the sash in hung windows from hitting when opened.
  • Stress Crack – A stress crack in an insulated glass unit is a crack in the glass that occurs only on the inside lite of the piece of insulating glass, usually from a rapid change in temperature. A stress crack starts as a single crack from near the edge of the unit, which will often continue to “walk” across the glass.
  • Studs – Vertical wood framing members, which form a wall.
  • Super Spacer® - A solid silicone foam spacer covered with Mylar. It is sealed to the edge of the glass and then sealed with butyl for greater energy efficiency.

T

  • Tape Glazing - Two-sided tape used to secure and seal the glass to the sash.
  • Tempered Glass – Hardened glass use to meet specific building codes. Usually related to impact and glass breakage.
  • Thermal Barrier – A strip of non-conducting material, such as wood, vinyl or foam rubber, which is used to separate the inside and outside surfaces of a metal window sash or frame, or a metal door or sill to stop the conduction of heat to the outside (which results in a cold inside surface). Vinyl windows, because of their thermal efficiency, do not require a thermal barrier.
  • Tilt Latch - Mechanism that unlocks the sash and allows it to tilt in from the main frame.
  • Tilt Pin – A metal or hard plastic nail-like pin fastened to the sash to allow it to engage the balance shoe and from which the sash may tilt or pivot in.
  • Tinted Glass – Glass that has been given a slight shading or coloring to it, usually to control sunlight in very bright, high intensity sun locations. There are many colors available today such as bronze, gray, green, blue, etc.
  • Total Heat Loss – The total heat loss from a structure equal to the sum of the heat loss (transmission) and infiltration (air leakage).
  • Total Unit U- and R-values - The U- and R-values of the window calculated from the average of the center of glass, edge of glass and frame U- and R-values. It is the reciprocal of the R-value.
  • Transom – Generally refers to an opening or stationary sash above a door or window which serves a similar purpose to a side lite. A transom joint is the horizontal joining area between two window units, which are stacked one on top of another.
  • Trim – Exposed molding or framing around a window or door, on either the inside or outside, to cover the space between the window frame or jamb and the wall. (See Casing)
  • Twin Unit (Window) – Two windows separated by a mullion, forming a unit. Also called a twin unit. See Double Window.

U

  • U-Value - Amount of heat transferred through a material. The lower the U-value, the slower the rate of heat flow and the better the insulating quality.
  • Ultra-Violet – Type of radiation with wavelengths shorter than those of visible light and longer than those of X-rays. Causes sunburn, fading and breakdown of fabric, wood furniture and other exposed surfaces.
  • United Inches – The sum in inches of the width and height of a window unit. Common “call size” for replacement windows.
  • UV Block - The percent of ultraviolet rays blocked from being transmitted through the glass. The higher the number the lower the percentage of ultraviolet rays transmitted through the window.

V

  • Venting Window – Operating window such as a venting, awning, etc. One that opens for ventilation.
  • Vertical Sliding Window – One or more sashes that move in a vertical direction.
  • V-Groove – A V-Shaped groove cut into the surface of a glass pane for decorative purposes.
  • Visible Light Transmittance - The percentage of light that is transmitted through glass in the visible light spectrum (380 to 720 nanometers). The higher the number the higher the percentage of visible light transmitted through the window.

W

  • Warm Edge Itercept® Spacer - A unique, u-channel stainless steel piece is placed between the two panes of insulated glass to create an effective thermal barrier. This sealed, one-piece design helps to reduce conducted heat loss through the window.
  • Weatherstripping - Material used to form a weather-resistant seal around the operable sash.
  • Weep Holes - Small openings at the bottom designed to allow water to escape that might otherwise accumulate in a window's sill.
  • Window Frame – The fixed frame of a window, which holds the sash as well as the operating hardware for the window.
  • Window Screen – Woven mesh of metal, plastic, or fiberglass stretched over a window opening to permit air to pass through, but not insects.