Argon Gas: Argon is a safe, odorless, colorless, non-toxic, non-flammable inert gas that is commonly used in place of air between the glass panes of an insulated Low-E glass unit to reduce temperature transfer
Asphalt: A bituminous waterproofing agent applied to roofing materials during manufacturing. Asphalt plastic roofing cement: An asphalt-based cement used to bond roofing materials.
Base Flashing: That portion of the flashing attached to or resting on the deck to direct the flow of water onto the roof covering.
Bay Window: A composite of three windows, usually made up of a large center fixed unit and two flanking units at 30°,45° or 90° degree angles to the wall.
Beading: This architectural term refers to a narrow, half-round molding that spans the edge of the siding.
Beveled Exterior: An angled extension from the frame that adds an aesthetically-pleasing dimension to the exterior of the window.
Block Frame Window: Used when replacing the wood sash of an old double hung wood window.
Bow Window: A composite of four or more window units in a radial or bow formation.
Bundle: A package of shingles. There are 3, 4 or 5 bundles per square.
Butt Edge: The lower edge of the shingle tabs
Casement Window: A window unit in which the single sash cranks outward, to the right or left.
Casing: Molding of various widths, thickness and shapes applied to the framework of window and door units.
Caulk: A mastic compound for filling joints and sealing cracks to prevent leakage of water and air, commonly made of silicone, bituminous, acrylic, or rubber-based material.
Caulking: To fill a joint with mastic or asphalt cement to prevent leaks.
Clapboard: A thin, narrow board with one edge thicker than the other, used as siding. CertainTeed siding brands offer clapboard-style siding in different exposures, several different textures, and even different panel projections.
Collar: Pre-formed flange placed over a vent pipe to seal the roof around the vent pipe opening. Also called a vent sleeve.
Conduction: Energy transfer from one material to another by direct contact.
Convection: Heat transfer by currents that flow from a warm surface to a colder one.
Dormer: A space which protrudes from the roof of a house, usually including one or more windows.
Double-hung Window: A window unit that has two operable sashes which move vertically in the frame.
Downspout: A pipe for draining water from roof gutters. Also called a leader.
Drip Cap: A molding placed on the top of the head brickmold or casing of a window frame.
Drip Edge: A non-corrosive, non-staining material used along the eaves and rakes to allow water run-off to drip clear of underlying construction.
Double or Dual Glazing: Use of two panes of glass in a window to increase energy efficiency and provide other performance benefits.
Dutchlap: A beveled-edge siding panel that was popularized by early American settlers.
Emissivity: The relative ability of a surface to radiate heat.
Exposure: The width of each "board" of siding. Also called a reveal.
Extrusion: A form produced by forcing material through a die. Most window frames are clad with extruded vinyl or aluminum.
Fascia: Architecturally, "fascia" refers to a flat, horizontal band. A flat board that runs horizontally along the eaves of a roof, typically capping the ends of the roof rafters to give the roof edge a more finished look and provide a base for attaching gutters.
Fenestration: An architectural term referring to the arrangement of windows in a wall. From the Latin word, "fenestra," meaning window.
Fiberglass: A composite material made by embedding glass fibers in a polymer matrix. May be used as a diffusing material in sheet form, or as a standard sash and frame element.
Finish: Refers to the texture (and sometimes the gloss level) of a siding panel. For fiber cement, this refers to the coating used to finish the siding. Usually an opaque paint; solid or semi-transparent stain.
Fixed Window: Non-venting or non-operable window. Also known as picture window.
Flashing: A thin strip of metal or synthetic material that diverts water away from a window or skylight.
Frame: The enclosure in which window sash or door panels are mounted.
Frieze: The horizontal member connecting the top of the siding with the soffit.
Gable Roof: A type of roof containing sloping planes of the same pitch on each side of the ridge. Contains a gable at each end.
Gambrel Roof: A type of roof containing two sloping planes of different pitch on each side of the ridge. The lower plane has a steeper slope than the upper. Contains a gable at each end.
Glazing: Glass in a window or door; the act or process of fitting with glass.
Glazing Bead: A plastic or wood strip applied to the window sash around the perimeter of the glass.
Glazing Stop: The part of the sash or door panel which holds the glass in place.
Green: To advocate the sustainable management of resources, and the protection (and restoration, when necessary) of the natural environment through changes in public policy and individual behavior.
Gutter: The trough that channels water from the eaves to the downspouts.
Head: The main horizontal member forming the top of the window or door frame.
Header: A horizontal framing member placed over the rough opening of a window to prevent the weight of wall or roof from resting on the window frame.
Hopper: A window unit in which the top of the sash swings inward.
Insulating Glass: A combination of two or more panes of glass with a hermetically sealed air space between the panes of glass. This space may or may not be filled with an inert gas, such as argon.
Lift: A handle or grip installed on the bottom rail of the lower sash of a double-hung window to make it easier to raise or lower the sash.
Light or Lite: Glazing framed by muntins and/or sash in a window or door.
Lintel: A horizontal member above a window or door opening that supports the structure above.
Low-E Glass: A common term used to refer to glass which has low emissivity due to a film or metallic coating on the glass or suspended between the two lights of glass to restrict the passage of radiant heat.
Mullion: A wood or metal part used to structurally join two window or door units.
Muntin: Applies to any short or light bar, either vertical or horizontal, used to separate glass in a sash into multiple lights. Also called a windowpane divider or a grille.
Muntin Bar: Any small bar that divides a windows glass. Also called a grille or windowpane divider.
Overlap: Area where two pieces of lap siding are overlapped. This dimension is usually 1 1/4".
Panel Projection: The section of siding that projects from the wall. As a rule of thumb, a larger panel projection creates a more pronounced shadow line.
Picture: Non-venting or non-operable window. Also know as a fixed window.
Pitch: The degree of roof incline expressed as the ratio of the rise, in feet, to the span, in feet.
Profile: Side view of a siding or soffit panel.
Rail: The top and bottom horizontal members of the framework of a window sash.
Ridge: The uppermost, horizontal external angle formed by the intersection of two sloping roof planes.
Rise: The vertical distance from the eaves line to the ridge.
Rough Opening: The framed opening in a wall into which a window or door unit is to be installed.
R-Value: Resistance to thermal transfer or heat flow. Higher R-value numbers indicate greater insulating value.
Sash Lift: A protruding handle screwed to the inside bottom rail of the lower sash on a double-hung window.
Seat Board: A flat board cut to fit the contour of a bow or bay window and installed between the sills and the flat wall surface, providing a seat or shelf space.
Shadow Line: The shadow pattern cast by a particular siding in the sunlight. Shadow line is influenced by the style and panel projection of the siding.
Shims: Wood wedges (often wood shingles) used to secure the window or door unit in the rough or masonry opening in a square, level and plumb position during and after installation.
Sidelites: Narrow fixed units mulled or joined to door units to give a more open appearance.
Sill: The main horizontal member forming the bottom of the frame of a window or door.
Simulated Divided Lite: A method of constructing windows in which muntins are affixed to the inside and outside of a panel of insulating glass to simulate the look of true divided light.
Single Glazing: Use of single panes of glass in a window. Not as energy-efficient as double glazing.
Single-hung Window: A double-hung type of window in which the top sash is fixed or inoperable.
Slider Window: Both sashes slide horizontally in a double-sliding window. Only one sash slides in a single-sliding window. Ventilation area can vary from a small crack to an opening of one-half the total glass area. Screens can be placed on the exterior or interior of the window unit.
Slope: The degree of roof incline expressed as the ratio of the rise, in inches, to the run, in feet.
Soffit: Usually the underside of an overhang or eaves.
Stile: The main vertical members of the framework of a sash.
Strike Plate: Protects the jamb from the hardware latch on a door. Covers the latch and deadbolt.
Square: Unit of measure for siding equal to 100 square feet (or a 10-foot by 10-foot wall section).
Stool: An interior trim piece on a window which extends the sill and acts as a narrow shelf.
Stop Molding: A molding used to hold, position or separate window parts.
Tempered Glass: Glass manufactured to withstand greater than normal forces on its surface. When it breaks, it shatters into small pieces to reduce hazard. Standard on all doors and large fixed windows.
Thermal Break: The addition of a thermal insulating material between two thermally conductive materials.
Threshold: The bottom part of the door frame, i.e. the area you step on when entering or exiting through the doorway.
Transom: A small window that fits over the top of a door or window, primarily for additional light and aesthetic value.
True Divided Lite: A term which refers to windows in which multiple individual panes of glass or lites are assembled in the sash using muntins.
Vent: Any outlet for air that protrudes through the roof deck such as a pipe or stack. Any device installed on the roof, gable or soffit for the purpose of ventilating the underside of the roof deck.
Vent Unit: A window or door unit that opens or operates.
Vertical Siding: Also referred to as "panel siding", this rectangular shaped siding is typically manufactured in 4 x 8, 4 x 9 or 4 x 10 sizes. Vertical siding is never overlapped. Solid vinyl soffit can also be used as vertical siding.
Vinyl: A plastic material used for cladding or entire window units.