Replacement Windows Glossary

We have compiled some of the most common replacement windows terms that you can expect to run into and hear from other window professionals! Use this glossary as your guide when searching for your windows:

| A | B | C | D | E | F | G | H | I | J | K | L | M | P | R | S | T | U | V | W |

Aluminum Windows: A type of replacement windows. Read more about Aluminum replacement windows here.

Argon: This is a gas that exists in the space between the two panes in a double pane window with the purpose of increasing the energy efficiency of the window. Argon decreases the amount of convection between the panes of glass, not allowing air to move in the glass cavity. Argon is beneficial in regulating home temperature, most especially in climates where temperatures reach extreme heat / cold.

Awning Windows: This is a specific style of window. Read more about awning windows here.

Balance System: This is the mechanism in a single or double pane window that provides force to the bottom half of the window so it can be opened or closed easily. Older windows were constructed with a weight on a line that is hidden in the cavity of the adjacent wall. Modern window system use either constant force spiral springs or very small block and tackle arrangements.

Bay Window: This is another style of window, which you can learn more about here.

Bow Window: Also another style of construction of a window. Learn more here.

Box Stores: If you come across this term on our discussion board, it is referring to the large home improvement chains, such as Lowes, Home Depot and to some extent Sears.

Capping: This is the process of finishing off the exterior portion of the newly installed window by applying aluminum or vinyl sheeting cut and formed to fit over the exterior trim. It is intended to not only make a window look great but to also provide a weather-proof seal.

Casement Windows: This is another construction style of a window, which you can see more about here.

Clad: Refers to the portion of a wood window or door that’s covered with aluminum, fiberglass or vinyl on the exterior side of the frame and sash.

Condensation: This is a process of moisture forming on the interior of a glass window often resulting in frost forming on the inside of the window.

Contract: This is the agreement a homeowner makes with the company installing the new windows defining exactly what the company will do, price it will cost, service details and warranty. This contract should always be provided to a homeowner in writing.

Contractor License: For any type of home improvement work, the company conducting the work needs to have a license to perform said work. The specific type varies from state to state. It is always a good idea for the homeowner to request a copy of required licenses.

Desiccant: Is a drying agent that is placed inside the panes of glass in a double or triple pane window to absorb any moisture that may get between the glass panes.

Double Hung Windows: This is the most common window style – learn more about it here.

ENERGY STAR: The ENERGY STAR Windows Program helps consumers and businesses find energy efficient products, including replacement windows. Learn more here.

Fiberglass Windows: A replacement window material. Learn more here.

Fibrex: Is a material made of co-polymers (epoxy) and wood by-products, is manufactured by Andersen, and sold through Renewal by Andersen. Read more on Fibrex here.

Fixed Frame: A style of window that do not open/close. Learn more here.

Foam Filled Frame: This involves filling the cavity in the frame of a vinyl replacement window with insulating foam, generally a spray polyurethane. Window frames are generally hollow in nature since they need to be a certain thickness to go from the outside of a wall to the inside of the wall. Windows with frames filled with foam provide greater insulating properties.

Glazing: The glass portion of a window or door. Common types of glazing used in building applications include clear and tinted float glass, tempered glass, laminated glass, and a variety of coated glasses. “Glazing” also refers to the actual process of installing the glass in a sash, frame or door panel.

Hardware: This applies to the locks, crank handles, and hinges on windows and doors used to operate and secure them.

Heat Gain: The amount of heat gained from direct sunlight and absorbed heat. Also referred to as Solar Heat Gain.

Heat Lamp: Is a device a salesperson often uses to demonstrate the ability of a window to stop heat transfer. A thermometer will be placed on one side of the window, and then the heat lamp will be applied to the other.

Heat Mirror: It is an insulating glass system, or coated film suspended between the two panes of glass in an insulated unit. It is not the same as low-emissivity coating.

Installation: The process of removing the old windows and fitting in the new ones.

Insulation: When old windows are removed and replaced, there will be areas that will have voids that will need to be filled to avoid drafts / leaks. These cavities are generally insulated.

Jamb: The left and right vertical pieces forming the frame on a window or door.

Krypton: A gas between the panes in a double paned window – an alternative to Argon- known for its insulating properties.

Lead Paint: Paints manufactured prior to 1978 had lead as an ingredient. Lead in paints pose a safety hazard to the inhabitants of a dwelling as the paint aged, cracked, peeled, and became accessible to ingestion particularly with children.

Low-E: A term meaning low “emissivity”. Emissivity is a property unique to materials like glass, which light can freely pass through. Low-E is a metallic coating used to reflect heat (energy) – filtering out the part of the light spectrum that transmits heat. It is applied as a thin coat on the panes of glass.

Muntin Bars: The narrow, horizontal and/or vertical bars that form the decorative grille pattern on a window.

Pane: A single piece of glass within a window or door.

R Value: The measure of a material’s resistance to the ability of heat to flow through it. A high number is superior. To read more on R Value here.

Replacement Windows: This is a catch-all phrase for a window that is designed to be used when old windows are removed from a building or house and a new window unit is installed.

Roll Form Aluminum: There are two types of aluminum used in window manufacturing; roll formed and extruded. Roll form is thinner and finished prior to bending in the manufacturing process.

Sash: This the term for the fixed or operating portion of the window consisting of top and bottom horizontal rails, left and right vertical stiles, and the glass.  See more here.

Sill: The horizontal piece forming the bottom of the frame on a window or door. See more of the anatomy of a window.

Single Hung: Is a window style with two sashes, learn more here.

Skylight: A style of replacement window. Learn more about it here.

Slider: A moving style of replacement window. See more here.

Solar Heat Gain Coefficient (SHGC): Measures how well a window or door prevents heat from passing through it. Learn more.

Spacer: An important part of a double or triple pane window- it is the material that separates, but also binds together, the panes of glass.

Spiral Balance: Helps the top half of a double hung window stay up, and makes it easier to open and close. A spiral balance uses a metal rod that that has spiral grooves in it that works against a gear on the sash- similar to a bolt and nut.

Tempered Glass: It is a process where glass panels are heated and then cooled rapidly in a controlled environment with the purpose to make them stronger than regular glass. It also makes it safer because it breaks it yields small pebble-like fragments without sharp edges.

Triple Pane Windows (Triple Hung Windows): Most replacement windows today are double paned windows which means there are two independent sections of glass kept apart at approximately 5/8 of an inch. When you have a triple pane window, that means there are three sections of glass.

U-Factor (U Rating or U Value): A measure of how much energy a material conducts. The lower the U-Value, the greater the insulating effect. Learn more here.

Vinyl Windows: A type of material for replacement windows. Learn more about them here.

Weather-Stripping: A strip of material designed to seal the sash and frame in order to reduce air and water infiltration.

Wood Windows: Material for replacement windows. Read more about it here.

Wrapped: The application and process of bending custom aluminum to fit around the outside sills and casing.