Home Improvement Glossary

 

Basic Terms & Definitions

 

 

ROOFING

Architectural Shingles: Also called laminated or dimensional shingles. Composed of heavy fiberglass mat base and ceramic-coated mineral granules that are tightly embedded in carefully refined, water-resistant asphalt. Sturdier and 50% heavier than 3-tab shingles.

ARMA: The Asphalt Roofing Manufacturers Association, a trade association for North American manufacturers of asphalt roofing.

ASTM International: A voluntary organization concerned with development of consensus standards, testing procedures and specifications.

Bundle: A package of shingles. There are between 15 and 29 shingles in a bundle. A bundle typically covers 33 square feet.

Butt: Portion of shingle that is exposed to the weather, also called a tab.

Dormer: Smaller roof projection from main roof, usually with a window.

Drip-edge: A type of angled roof flashing designed to allow water run-off without damaging underlying roofing materials.It is typically constructed from aluminum, copper, or steel, and runs along the edges of the roof of an entire house. Drip edges consist of three main types - L, C, and T, differentiated by their shape. A drip edge is now required in most states for a roof to meet code requirements.

Eave: The eave of a roof is the edge of the roof that hangs over a building wall and usually projects beyond the side of a building.

Fascia: The long, straight board that runs along the lower edge of the roof and supports the bottom row of tiles and the guttering.The fascia is also called “transition trim” and helps your roof to appear finished, while also protecting your house from moisture.

Felt: Roofing felt acts as a base material to protect the roof deck. Roofing felt is a type of underlayment that includes tar paper as an option.

Flashing: A thin metal material (usually galvanized steel) that surrounds areas where the roof plane meets a vertical surface - such as vents, chimneys, valleys, joints, and skylights - to direct water away from these areas.This protects the openings and cracks of a roof from water damage.

Gable: The typically triangular wall at the end of a roof, between the edges of intersecting roof pitches.

Gable roof: A roof with two sloping sides and a gable at each end; the intersecting roof pitches form a ridge.

Hip roof: Roof with four sides.

Mansard roof: A French roof design with four sides in which the slope becomes steeper halfway down.

Pitch: Measurement of how steep a roof slope is; the ratio is rendered inches of rise per every 12 inches of depth (6/12, 12/12, etc.)

Rafters: The supporting framing to which a roof deck is attached.

Rake: The inclined edge of a roof over a wall.

Ridge: The top edge of two intersecting sloping roof surfaces.

Ridge Vent: Rigid vent mounted along the main ridge of the house.

Shake: Wooden shingles split by hand from lumber logs (typically cedar) using special crafting tools.

Sheathing: Also known as decking or roof deck. The materials (typically plywood) that are fastened to rafters to cover a house or building to which roofing materials are applied.

Slope: The degree of incline of a roof plane, measured by rise in inches for each 12 inches of horizontal run (e.g., a roof with a 4-in-12 slope rises 4 inches for every foot of horizontal distance).

Soil Stack: A vent pipe that penetrates the roof.

Soffit: The finished underside of an eave.

Span: The horizontal measurement from eave to eave.

Spire: A tower of roof tapering up to a point.

Square: Common measurement for roof area in which 1 square = 100 ft².

Truss: Engineered components for specific applications that supplement rafters in many newer homes and buildings.

Underlayment: A sheet of asphalt-saturated felt used as a secondary layer of protection over the roof deck and under the roofing material.

Valley: The angle formed at the intersection of two sloping roof surfaces.

 

WINDOWS

Anchor Strip: Board around a window frame nailed to house framing. It also serves as a windbreak. In newer windows, the anchor strip may be plastic or metal.

Apron: horizontal trim board under a window stool.

Awning window: A window that is top-hinged and operated by an interior device so that it opens outward, admitting air but excluding rain.

Bay Window: Three-window unit that projects out from the wall and either extends to the ground or is half-height and supported from above or below. An "angle bay window" refers to the angle of departure from the plane of the wall. 

Bow Window: Multi-window unit projecting outward, composed of more than three panels set at a 10 degree angle to form a bow shape.

Casement window: A window that is hinged on the side, opening outward and held open using a casement stay; can be in pairs or single windows.

Casing: The trim or molding around a window that forms the frame.

Double glazing: Windows that are constructed using two panes of glass per window sash, with the space between panes often separated by gas.

Double-hung Window: A type of window that includes two sashes that move independently, sliding up and down to provide ventilation; also known as a “double-sash” window.

Drip cap: A horizontal molding to divert water from the top casing so water drips beyond the outside of the frame.

Frame: The part of a window that supports the glass panes and the entire window system, comprising the head, jamb and sill.

Fiberglass windows: Window frames that are made of fiberglass; they resist rot, warp, and degrading, and are easy to repaint.

Glazing: The windows in a finished home; also the act of installing glass.

Header: The supporting member or beam above window opening which transfers building weight above to the supporting wall structure on each side of the window. The term header is generally in reference to a wood beam, whereas "Lintel" often refers to a steel beam.

Insulating glass: An insulating glass window combines two or more panes of hermetically-sealed glass.

Jamb: Main, vertical lengths of wood that both form and support the sides of a window frame and are flush with the interior wall surface. 

Low E (Low Emission): A transparent, micro-thin, metallic coating, applied to the interior side of the insulated glass unit. It reflects radiated heat and allows solar heat to pass.

Mullion: The vertical piece of framing used in windows as a support piece for the glass.

Pane: The glass piece(s) used in a window.

Rail: A horizontal member of a sash, leaf, or panel.

R-Value: Measures the resistance of a material to heat transmission. A higher “R” value is desirable because it means more solar heat is absorbed through the window.

Sash: the members of a window, secondary storm product, or unit skylight that fit within a frame which are designed to accommodate the glazing.

• Center-hung Sash: a sash that pivots on pins in the middle of the sash stiles and sides of the window frame to allow access for cleaning from the inside.
• Hanging (Hung) Sash: A sash hung on a cord connected to a counterweight.

Sill: A horizontal member at the bottom of the window frame; a masonry sill or sub-sill can be below the sill of the window unit.

Single glazing: A window constructed using a single pane of glass per sash.

Skylight: A lighting structure installed in the roof/ceiling of a building to allow natural light in. Skylights can also offer ventilation.

Stile: A vertical member of a sash, leaf, or panel. 

Stool: The bottom, flat, interior part of a window on which the sash rests when it is closed. A typical sash extends inward to about a 3” depth forming a shallow shelf of sorts.

Storm window: A window layer, either permanent or temporary, that can be installed on the exterior of a window to protect against the elements.

Tempered glass: Glass that has been processed using intense heating/cooling to force compression and make for a stronger final product that is hard to break and will "pelletize" instead of shattering. 

Thermal barrier: an element made of material with relatively low thermal conductivity, which is inserted between two members having high thermal conductivity, in order to reduce the heat transfer.

Vinyl windows: Windows constructed using PVC material; an affordable, low-maintenance option.

Weather-stripping: Various products (metal, wood or plastic) that can be applied to window and/or door frames to seal openings or cracks where air and water could enter; also, the process of applying these materials. 

Wood-Clad Window: A window with an interior traditional wood frame paired with a weather-resistant exterior frame.