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Glossary · 71 termsWindow and Door Glossary
Short definitions for the words you hear when a window or door needs work, from argon gas to weep holes. Search a term or browse by topic.
Aluminum storefront
CommercialThe aluminum framing system that holds the large glass panels and doors on most shop and office fronts. Glass, doors, closers and seals in these systems can usually be repaired one piece at a time.
Storefront Glass and Doors →Argon gas
Energy and ratingsA clear, harmless gas sealed between the panes of many double-pane windows. It slows heat loss better than air. When the seal fails, the argon leaks out and the window insulates less.
Foggy Window Repair →Awning window
Window and door typesA window hinged at the top that swings outward from the bottom, usually opened with a crank. It can stay open in light rain.
Locks, Cranks and Hardware →Balance
Hardware and balancesThe spring or weight system in the side of a double-hung or single-hung window that holds the sash up. Worn balances are why windows slam shut or will not stay open.
Sash and Balance Repair →Bay window
Window and door typesA group of three or more windows that project out from the wall, usually a large center window with angled side windows.
Window Repair →Block-and-tackle balance
Hardware and balancesA balance that uses a cord and pulleys inside a metal channel to hold a sash up. Common in vinyl and aluminum double-hung windows.
Sash and Balance Repair →Board-up
Problems and repairsCovering a broken window or door with plywood to keep out weather and intruders until new glass or repairs are installed.
Board-Up Service →Brick molding
Window and door partsThe exterior trim around a window or door that covers the gap between the frame and the brick or siding.
Window Frame and Sill Repair →Casement window
Window and door typesA window hinged on the side that swings outward like a door, opened with a crank. Worn cranks and hinges are a common repair.
Locks, Cranks and Hardware →Casing
Window and door partsThe interior trim around a window or door opening.
Caulk
Problems and repairsA flexible sealant used to close gaps around frames, trim and glass. Cracked caulk lets water in and is a common cause of sill rot.
Window Frame and Sill Repair →Condensation
Problems and repairsMoisture that forms on glass. On the room side it usually means high indoor humidity. Between the panes, it means the seal has failed.
Foggy Window Repair →Constant force balance
Hardware and balancesA balance that uses a coiled metal spring to hold a tilt-in sash. When the spring breaks, the sash drops.
Sash and Balance Repair →Crank
Hardware and balancesThe handle and gear box (operator) that opens a casement or awning window. A crank that spins without moving the window has stripped gears.
Locks, Cranks and Hardware →Divided lites
Window and door partsGlass split into smaller panes by bars. True divided lites use separate pieces of glass; simulated ones use bars on or between a single glass unit.
Door closer
CommercialThe arm and hydraulic cylinder that closes a door automatically and controls its speed. Leaking or worn closers make doors slam or stay open.
Commercial Door Repair →Door jamb
Window and door partsThe vertical parts of a door frame. The strike side is often split in break-ins and can be repaired and reinforced.
Door Repair →Door sweep
Window and door partsA strip of rubber or brush on the bottom of a door that blocks drafts and water.
Door Repair →Double-hung window
Window and door typesA window with two sashes that both slide up and down. The most common window in Chicago-area homes.
Sash and Balance Repair →Double-pane glass
GlassTwo sheets of glass sealed together with a spacer and a sealed air or gas space between them. Also called insulated glass.
Window Glass Replacement →Egress window
Window and door typesA window large enough to escape through in an emergency, required in bedrooms, including basement bedrooms.
Failed seal
Problems and repairsWhen the edge seal of a double-pane unit breaks down, moist air gets between the panes and the glass fogs. The fix is a new sealed glass unit.
Foggy Window Repair →Frame
Window and door partsThe fixed outer part of a window that holds the sashes or glass and attaches to the wall.
Window Frame and Sill Repair →French door
Window and door typesA pair of hinged doors with large glass panels, often opening to a patio or between rooms.
Door Repair →Glazing
GlassThe glass in a window or door, or the act of installing it.
Window Glass Replacement →Glazing bead
Window and door partsA strip of vinyl, wood or metal that holds the glass in the sash. Many glass replacements start by removing the beads.
Window Glass Replacement →Glazing putty
GlassThe compound that holds and seals glass in older wood windows. When it dries and cracks, glass rattles and water gets in.
Wood Window Repair →Hinge
Hardware and balancesThe pivot that lets a casement window, awning window or door swing. Worn hinges make windows and doors drag or sag.
Locks, Cranks and Hardware →Insulated glass unit (IGU)
GlassThe sealed double- or triple-pane glass assembly in most modern windows. When it fogs or cracks, the IGU is replaced and the frame stays.
Foggy Window Repair →Jamb
Window and door partsThe sides of a window or door frame.
Window Frame and Sill Repair →Keeper
Hardware and balancesThe part a sash lock hooks into. If the lock will not catch, the keeper or the sash alignment usually needs adjusting.
Locks, Cranks and Hardware →Laminated glass
GlassTwo layers of glass bonded to a plastic interlayer. It holds together when broken, which adds security and safety.
Storefront Glass and Doors →Low-E coating
Energy and ratingsA thin, invisible metal coating on glass that reflects heat, keeping rooms warmer in winter and cooler in summer.
Window Glass Replacement →Molding
Window and door partsWood or composite strips that frame a window or door. Outside, brick molding covers the gap between the frame and the wall; inside, the molding is usually called casing. Rotted or split molding can be repaired or replaced without replacing the window.
Mortise lock
Hardware and balancesA lock set into a pocket in the edge of a door, common on sliding patio doors and commercial doors.
Sliding and Patio Door Repair →Mullion
Window and door partsA vertical or horizontal bar between two separate windows or units joined in one opening.
Muntin
Window and door partsA thin bar that divides glass into smaller panes inside a single sash.
NFRC label
Energy and ratingsThe National Fenestration Rating Council label on new windows and doors that lists ratings such as U-factor and solar heat gain.
Window Replacement →Obscure glass
GlassTextured or frosted glass that lets light through while blocking the view, used in bathrooms and entry doors.
Window Glass Replacement →Operator
Hardware and balancesThe crank mechanism that opens and closes casement and awning windows.
Locks, Cranks and Hardware →Panic bar
CommercialA push bar on a commercial exit door that unlatches when pressed. Also called exit hardware.
Commercial Door Repair →Patio door
Window and door typesA large glass door to a patio or deck, usually sliding or hinged like a French door.
Sliding and Patio Door Repair →Picture window
Window and door typesA large fixed window that does not open, used for views and light.
Window Glass Replacement →Pivot
CommercialThe hardware at the top and bottom of many storefront doors that the door swings on. Worn pivots make doors drag.
Storefront Glass and Doors →Pivot bar and balance shoe
Hardware and balancesThe parts at the bottom corners of a tilt-in sash that ride in the balance and let the sash tilt. Broken shoes make sashes drop or jam.
Sash and Balance Repair →Rail
Window and door partsThe horizontal top and bottom parts of a sash or door.
Rollers
Hardware and balancesThe wheels at the bottom of a sliding door or window. Worn rollers make sliding doors heavy and noisy.
Sliding and Patio Door Repair →Rot
Problems and repairsDecay in wood caused by trapped moisture. It usually starts at sills, bottom rails and corners where paint or caulk has failed.
Window Frame and Sill Repair →Sash
Window and door partsThe movable part of a window that holds the glass.
Sash and Balance Repair →Sash cord and weights
Hardware and balancesThe rope and iron weights hidden in the frame of older wood windows that balance the sash. Broken cords can be restrung.
Wood Window Repair →Sash lock
Hardware and balancesThe latch where the two sashes of a double-hung window meet. It locks the window and pulls the sashes tight to stop drafts.
Locks, Cranks and Hardware →Sill
Window and door partsThe bottom part of a window frame, which sheds water. Sills are the most common place for rot.
Window Frame and Sill Repair →Single-hung window
Window and door typesA window where only the bottom sash moves. The top sash is fixed.
Sash and Balance Repair →Sliding window
Window and door typesA window whose sash slides sideways on a track.
Window Repair →Spacer
GlassThe strip that separates the panes of glass around the edge of an insulated glass unit and holds the seal.
Foggy Window Repair →Spiral balance
Hardware and balancesA balance with a twisted rod inside a tube that holds a sash up. Common in vinyl and wood tilt-in windows.
Sash and Balance Repair →Stile
Window and door partsThe vertical side parts of a sash or door.
Stool
Window and door partsThe interior shelf at the bottom of a window, often mistaken for the sill.
Storefront
CommercialThe glass front of a shop or office at street level, including fixed glass and entry doors.
Storefront Glass and Doors →Storm window
Window and door typesAn extra window installed outside or inside the main window to add insulation and protection.
Window Repair →Tempered glass
GlassSafety glass heat-treated to be about four times stronger than regular glass. It breaks into small pieces and is required in doors and near floors.
Window Glass Replacement →Tilt latch
Hardware and balancesThe latches at the top of a tilt-in sash that let it tilt inward for cleaning.
Sash and Balance Repair →Track
Window and door partsThe channel a sash or sliding door runs in. Dirty or bent tracks make windows and doors stick.
Sliding and Patio Door Repair →Transom
Window and door typesA small window above a door or another window.
Trim
Window and door partsA general name for the finish pieces around a window or door, including casing, stool, apron and exterior molding. Damaged trim lets water and drafts in around the frame.
Triple-pane glass
Energy and ratingsAn insulated glass unit with three sheets of glass for extra insulation and sound control.
Window Replacement →U-factor
Energy and ratingsA rating of how much heat a window lets escape. Lower is better.
Window Replacement →Vinyl window
Window and door typesA window with frames and sashes made of PVC. Common in replacement windows from the 1990s on.
Window Repair →Weatherstripping
Window and door partsThe strips of foam, rubber or pile that seal the gaps between sashes, frames and doors. Worn weatherstripping causes drafts.
Window Repair →Weep holes
Problems and repairsSmall openings at the bottom of a window frame that let water drain out. When they clog, water can back up and leak inside.
Window Repair →Window stop
Hardware and balancesA device that limits how far a window opens, for safety and security.
Locks, Cranks and Hardware →No terms match that search. Try another word, or ask us.
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