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AAMA: American Architectural Manufacturers Association. A national trade association that establishes voluntary standards for the window, door, storefront, curtain wall and skylight industries.

Air infiltration: The amount of air leaking in and out of a building through cracks in walls, windows and doors.

Algae discoloration: A type of roof discoloration caused by algae. Commonly called fungus growth.

Argon gas: An inert, nontoxic gas used in insulating glass units to reduce heat 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. Also known as flashing cement or mastic; should conform to ASTM D-4586.

ASTM: American Society for Testing and Materials. Organization that develops methods for testing of materials.

Awning window: A window that is hinged at the top and swings outward for ventilation.

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Backerboard: A flat material used on the face of the house, between the studs and the siding, to provide a nailable surface for the siding.

Balance covers: A snap in covering that conceals the EvenForce™ block and tackle balance system within the window frame, helping to keep dirt and dust out of the chamber.

Balanced system: A ventilation system where 50% of the required ventilating area is provided by vents located in the upper portion of the roof with the balance provided by undereave or soffit vents.

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: An angled combination of three windows that project out from the wall of the home. The windows are usually positioned at 30- or 45-degree angles.

Beveled MasterFrame: Some Alside windows feature a unique fusion-welded design that accommodates differing installation methods and architectural styles. It is the angled portion of the masterframe profile that adds a three dimensional appearance to the exterior of the window.

Bow window: An angled combination of windows in 3-, 4- or 5-lite configurations. As the windows are joined to each other, they combine to form an arch shape that projects from the wall of the home.

Blisters: Bubbles that may appear on the surface of asphalt roofing after installation.

Block and Tackle Balance System: The block and tackle system utilizes a high-density nylon cord pulley action which is attached to a moveable block that travels up and down within a metal chamber. Tension from a heavy duty coil spring at the top of the block creates the proper resistance necessary for smooth operation of the window sash.

Built-up roof: A flat or low-sloped roof consisting of multiple layers of asphalt and ply sheets.

Bundle: A package of shingles. There are 3, 4 or 5 bundles per square.

Butt edge: The lower edge of the shingle tabs.

Buttlock: The bottom edge of a siding or soffit panel, or accessory piece, opposite the nailing slots, which locks onto the preceding panel.

Butyl: A rubber material that seals the glass to the spacer, creating an airtight and water-tight insulated glass unit.

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Cam-action lock and keeper: The mechanisms, which pull and secure the sashes together when placed in the locked position.

Casement window: A window with a side-hinged sash that opens and closes outward by a crank handle mechanism. Available in continuous mainframe, with multi-lite configurations.

Caulk: To fill a joint with mastic or asphalt cement to prevent leaks.

Chalk line: A line made on the roof by snapping a taut string or cord dusted with chalk. Used for alignment purposes.

Channel: The area of the accessory trim or corner post where siding or soffit panels are inserted. Channels also refer to the trim itself, and are named for the letters of the alphabet they resemble (e.g., J-channel, F-channel, etc.).

ClarityOne Glass: A chemical treatment that when applied to glass, helps to create a smoother surface that won’t attract or hold dirt and dust. Established by PPG Industries.

Class "A": The highest fire-resistance rating for roofing as per ASTM E-108. Indicates roofing is able to withstand severe exposure to fire originating from sources outside the building.

Class "B": Fire-resistance rating that indicates roofing materials are able to withstand moderate exposure to fire originating from sources outside the building.

Class "C": Fire-resistance rating that indicates roofing materials are able to withstand light exposure to fire originating from sources outside the building.

ClimaTech®: The brand name for the insulated glass unit that is present in Alside’s insulating glass packages. A ClimaTech unit will contain either two or three panes of glass, with one or two of those panes being a Low E surface. It will utilize the SST warm edge spacer system and contain either argon or krypton gas.

Closed cut valley: A method of valley treatment in which shingles from one side of the valley extend across the valley while shingles from the other side are trimmed two inches from the valley centerline. The valley flashing is not exposed.

Collar: Pre-formed flange placed over a vent pipe to seal the roof around the vent pipe opening. Also called a vent sleeve.

Concealed nail method: Application of roll roofing in which all nails are driven into the underlying course of roofing and covered by a cemented, overlapping course. Nails are not exposed to the weather.

Condensation: The deposit of water vapor from the air on any cold surface whose temperature is below the dew point, such as a cold window glass or frame that is exposed to humid indoor air.

Coved glazing beads: A contoured piece of vinyl that holds the glass in place within the sash and adds an elegant, finished look.

Counter flashing: That portion of the flashing attached to a vertical surface to prevent water from migrating behind the base flashing.

Course (Siding): A row of panels, one panel wide, running the length of the house from one side to the other, or, in the case of vertical siding, from top to bottom.

Course (Roofing): A row of shingles or roll roofing running the length of the roof.

Cricket: A peaked saddle construction at the back of a chimney to prevent accumulation of snow and ice and to deflect water around the chimney.

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Damper: An adjustable plate for controlling draft.

Deck: The surface installed over the supporting framing members to which the roofing is applied.

Dormer: A framed window unit projecting through the sloping plane of a roof.

Double Channel Lineal: A siding accessory that joins two soffit panels.

Double coverage: Application of asphalt roofing such that the lapped portion is at least two inches wider than the exposed portion, resulting in two layers of roofing material over the deck.

Double-hung window: A window that has two vertical operating sashes.

Downspout: A pipe for draining water from roof gutters. Also called a leader.

Drip Cap/Head Flashing: An accessory installed with vertical siding to ensure that water drips away from panels and does not infiltrate them; it is also used as a vertical base.

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.

Dutch lap method: Application of giant individual shingles with the long dimension parallel to the eaves. Shingles are applied to overlap adjacent shingles in each course as well as the course below.

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Eaves: The horizontal, lower edge of a sloped roof.

Eaves flashing: Additional layer of roofing material applied at the eaves to help prevent damage from water back-up.

Edging strips also know as D-Edge or Drip Edge: Boards nailed along eaves and rakes after cutting back existing wood shingles to provide secure edges for reroofing with asphalt shingles.

E-Gard®: Brand name for specially coated, operating hardware that helps to resist oxidation and corrosion.

Egress Code: The minimum opening of a window for people to exit or firefighters to enter a building/dwelling. Different states or regions have different code requirements.

Ell: An extension of a building at right angles to its length.

ENERGY STAR®: The ENERGY STAR program is a joint venture between the US Environmental Protection Agency (EPA) and the US Department of Energy (DOE) designed to encourage homeowners to purchase energy-efficient products. Using less energy in our homes reduces the amount of CO2 emissions released into the atmosphere from burning fossil fuels such as coal, oil and natural gas. The advanced components and design in the ClimaTech™ insulated glass package exceed all performance criteria required by the ENERGY STAR program.

Exposed nail method: Application of roll roofing in which all nails are driven into the cemented, overlapping course of roofing. Nails are exposed to the weather.

Exposure I grade plywood: Type of plywood approved by the American Plywood Association for exterior use.

EvenForce™: Alside’s brand name for its block and tackle balance system. A balance system is a device for holding the vertically sliding sashes in any desired position within the window mainframe.

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Face: Refers to the side of a siding or soffit panel that is showing once the panel has been installed.

Face-nailing: The action of fastening directly onto the “face” side of a panel (instead of using the nail hem slot). This practice is generally not used in siding installation.

Fascia Board: A board attached to the ends of the rafters between the roofing material and the soffit overhang. Fascia cap is the covering around that board.

Feathering strips: Tapered wood filler strips placed along the butts of old wood shingles to create a level surface when reroofing over existing wood shingle roofs. Also called horsefeathers.

Felt: Fibrous material saturated with asphalt and used as an underlayment or sheathing paper.

Fenestration: The placement of window openings in a building wall, one of the important elements in controlling the exterior appearance of a building. Also, a window, door or skylight and its associated interior or exterior elements, such as shades or blinds.

Fiber glass mat: An asphalt roofing base material manufactured from glass fibers.

Fixed Lite: A pane of glass installed directly into non-operating framing members; also, the opening or space for a pane of glass in a non-operating frame.

Fixed Panel: An inoperable panel of a sliding glass door or slider window.

Fixed Window: A window with no operating sashes.

Flashing(Roofing): Pieces of metal or roll roofing used to prevent seepage of water into a building around any intersection or projection in a roof such as vent pipes, chimneys, adjoining walls, dormers and valleys. Galvanized metal flashing should be minimum 26-gauge.

Flashing(siding): A thin, flat material, usually aluminum, positioned under or behind J-channels, corner posts, windows, etc., to keep draining water from penetrating the home.

Flashing Cement: See asphalt plastic roofing cement.

Free-tab shingles: Shingles that do not contain factory-applied strips or spots of self-sealing adhesive.

French patio doors: A two panel glass door where both panels operate and swing either inward or outward.

Furring/Furring Strip: A wooden or steel framing material, usually 1" x 3", used to provide an even nailing base. To “fur” a surface means to apply these strips.

Fusion-welded: The process of joining materials by melting them together with extreme heat (in most cases over 500ºF), resulting in the materials combining into a one-piece unit.

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Gable: The upper portion of a sidewall that comes to a triangular point at the ridge of a sloping roof.

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.

Garden window: Designed much like a bay or bow window, a garden also extends from the wall to the exterior of the home. It is built in a square or rectangular shape at right angles. The two side lights often operate for added ventilation.

Gas Fill: A gas other than air, usually argon or krypton, placed between window or skylight glazing panes to reduce the U-factor by suppressing conduction and convection.

Glazing: The glass or plastic panes in a window, door or skylight.

Glazing Bead: A molding or stop around the inside of a window frame to hold the glass in place.

Granules: Ceramic-coated colored crushed rock that is applied to the exposed surface of asphalt roofing products.

Grids: Optional horizontal or vertical lineals installed between the glass panes help to create the appearance of a divided window design.

Gutter: The trough that channels water from the eaves to the downspouts.

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Head lap: Shortest distance from the butt edge of an overlapping shingle to the upper edge of a shingle in the second course below. The triple coverage portion of the top lap of strip shingles.

HEX shingles: Shingles that have the appearance of a hexagon after installation.

Hinged patio doors: A two panel glass door where one panel is stationary or fixed, while the other operates and swings either inward or outward.

Hip: The inclined external angle formed by the intersection of two sloping roof planes. Runs from the ridge to the eaves.

Hip roof: A type of roof containing sloping planes of the same pitch on each of four sides. Contains no gables.

Hip shingles: Shingles used to cover the inclined external angle formed by the intersection of two sloping roof planes.

Hopper window: A bottom-hinged sash window that opens inward for ventilation.

Horsefeathers: See feathering strips.

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Ice dam: Condition formed at the lower roof edge by the thawing and re-freezing of melted snow on the overhang. Can force water up and under shingles, causing leaks.

Insulating air chambers: Various chambers within the sash and master frame, which help to insulate and strengthen the window.

IntegraWeld: The fusion-welding process of some Alside windows.

Interlocking shingles: Individual shingles that mechanically fasten to each other to provide wind resistance.

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Jamb: A vertical member at the side of a window frame or the horizontal member at the top of the window frame, as in head jamb.

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Krypton gas: An inert, nontoxic gas used in insulating windows to reduce heat transfer.

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Laminated shingles: Strip shingles containing more than one layer of tabs to create extra thickness. Also called three-dimensional shingles.

Lap(Roofing): To cover the surface of one shingle or roll with another.

Lap(Siding): To overlap the ends of two siding panels or accessory pieces to allow for expansion and contraction of the vinyl product.

Lap cement: An asphalt-based cement used to adhere overlapping plies of roll roofing.

Lift Handle: for raising the lower sash in a double-hung window. Also called sash lift.

Lite: A unit of glass in a window.

Low E (Emissivity) Glass: Microscopically thin, virtually invisible, metal or metallic oxide layers deposited on a window or skylight glazing surface primarily to reduce the U-factor by suppressing radiative heat flow. A typical type of low-E coating is transparent to the solar spectrum (visible light and short-wave infrared radiation) and reflective of longwave infrared radiation.

Low slope application: Method of installing asphalt shingles on roof slopes between two and four inches per foot.

Louver: A slanted opening for ventilation.

Lug/Crimp: The raised “ears” or tabs on a siding panel, created by a snaplock punch, which can be used to lock a siding panel into place when the nailing hem has been removed.

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Mansard roof: A type of roof containing two sloping planes of different pitch on each of four sides. The lower plane has a much steeper pitch than the upper, often approaching vertical. Contains no gables.

Masterframe: The combination of the head, sill and jamb sections of a window.

Meeting rail: The part of a sliding glass door, a sliding window or a hung window where two panels meet and create a weather barrier.

Mineral stabilizers: Finely ground limestone, slate, traprock or other inert materials added to asphalt coatings for durability and increased resistance to fire and weathering.

Mineral-surfaced roofing: Asphalt shingles and roll roofing that are covered with granules.

Miter: To make a diagonal cut, beveled to a specific angle (usually 45°). Sometimes miter cuts are made into an overlapping siding or soffit panel surface, to provide a neater appearance.

Mylar: A weather-stripping material that is present where the sash frame meets the masterframe. Adds increased resistance to air infiltration.

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Nailing Hem (or Flange): The section of siding or accessories where the nailing slots are located.

Natural ventilation: A ventilation system utilizing ventilators installed in openings in the attic and properly positioned to take advantage of natural air flow to draw hot summer or moist winter air out and replace it with fresh outside air.

Nesting: A method of reroofing with new asphalt shingles over old shingles in which the top edge of the new shingle is butted against the bottom edge of the existing shingle tab.

Net free area: Area unobstructed by screens, louvers or other materials.

NFRC: National Fenestration Rating Council.

No-cutout shingles: Shingles consisting of a single, solid tab with no cutouts.

Non-veneer panel: Any wood based panel that does not contain veneer and carries an APA span rating, such as wafer board or oriented strand board.

Normal slope application: Method of installing asphalt shingles on roof slopes between 4 inches and 21 inches per foot.

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Obscure glass: Glass that has been made translucent instead of transparent.

Open valley: Method of valley construction in which shingles on both sides of the valley are trimmed along a chalk line snapped on each side of the valley. Shingles do not extend across the valley. Valley flashing is exposed.

Organic felt: An asphalt roofing base material manufactured from cellulose fibers.

Origin II™: The virgin uPVC vinyl used in all Alside windows. The material’s low thermal conductivity makes it the best choice for window manufacturing. Will not rot, peel, blister, swell or deteriorate from corrosion or pitting.

Overhang: That portion of the roof structure that extends beyond the exterior walls of a building.

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Pallets: Wooden platforms used for storing and shipping bundles of shingles.

Panel: A major component of a sliding glass door, consisting of a light of glass in a frame installed within the main (or outer) frame of the door. A panel may be sliding or fixed.

Picture window: A picture window that does not move or operate.

Pitch: The degree of roof incline expressed as the ratio of the rise, in feet, to the span, in feet.

Plastic Cement: A compound used to seal flashings and in some cases to seal down shingles as well as for other small waterproofing jobs. Where plastic cement is required for sealing down shingles, use a dab about the size of a quarter unless otherwise specified.

Plumb: A position or measurement that is truly and exactly vertical, 90° from a level surface.

Ply: The number of layers of roofing: i.e. one-ply, two-ply.

Positive Lock: Area below the nailing hem that the buttlock locks into.

Profile Describes the design of the panel (Clapboard, Dutch lap, Triple 3, etc.)

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Quick-setting cement: An asphalt-based cement used to adhere tabs of strip shingles to the course below. Also used to adhere roll roofing laps applied by the concealed nail method.

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Racking: Roofing application method in which shingle courses are applied vertically up the roof rather than across and up. Not a recommended procedure.

Radiation The transfer of heat in the form of electromagnetic waves from one separate surface to another. Energy from the sun reaches the earth by radiation and a person’s body can lose heat to a cold window or skylight surface in a similar way.

Rafter: The supporting framing member immediately beneath the deck, sloping from the ridge to the wall plate.

Rake: The inclined edge of a sloped roof over a wall from the eave to the ridge.

Random-tab shingles: Shingles on which tabs vary in size and exposure.

Release tape: A plastic or paper strip that is applied to the back of self-sealing shingles. This strip prevents the shingles from sticking together in the bundles, and need not be removed for application.

Ridge: The uppermost, horizontal external angle formed by the intersection of two sloping roof planes.

Ridge shingles: Shingles used to cover the horizontal external angle formed by the intersection of two sloping roof planes.

Rise: The vertical distance from the eaves line to the ridge.

Roll roofing: Asphalt roofing products manufactured in roll form.

Roofing tape: An asphalt-saturated tape used with asphalt cements for flashing and patching asphalt roofing.

R-value: A measure of the resistance of a glazing material or fenestration assembly to heat flow. It is the inverse of the U-factor (R = 1/U) and is expressed in units of hr-sq ft-ºF/Btu. A high-R-value window has a greater resistance to heat flow and a higher insulating value than one with a low R-value.

Run: The horizontal distance from the eaves to a point directly under the ridge. One half the span.

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Sash: Separate from the masterframe, the portion of the window that contains the glass.

Sash limit locks: A feature that allows a window to be safely raised to a certain height.

Saturant: Asphalt used to impregnate an organic felt base material.

Saturated felt: An asphalt-impregnated felt used as an underlayment between the deck and the roofing material.

Scoring: Running a utility knife blade, a sharpened awl, scoring tool, or other sharp implement across a soffit or siding panel face without cutting all the way through the panel. This weakens the vinyl surface in a specific area and allows the panel to be bent and broken off cleanly.

Self-sealing cement: A thermal-sealing tab cement built into the shingle to firmly cement the shingles together automatically after they have been applied properly and exposed to warm sun temperatures. In warm seasons, the seal will be complete in a matter of days. In colder seasons, sealing time depends on the temperature and amount of direct sunlight hitting the shingles. Hand sealing with plastic cement should be done to ensure sealing in winter.

Self-sealing shingles: Shingles containing factory-applied strips or spots of self-sealing adhesive.

Self-sealing strip or spot: Factory-applied adhesive that bonds shingle courses together when exposed to the heat of the sun after application.

Selvage: That portion of roll roofing overlapped by the succeeding course to obtain double coverage.

Shading: Slight differences in shingle color that may occur as a result of normal manufacturing operations.

Sheathing: Exterior grade boards used as a roof deck material.

Shed roof: A roof containing only one sloping plane. Has no hips, ridges, valleys or gables.

Sill: The horizontal, bottom section of the masterframe.

Single coverage: Asphalt roofing that provides one layer of roofing material over the deck.

Sliding patio doors: A combination of fixed and sliding glass door panels that operate solid brass roller trucks. Available in 2-, 3- or 4- lite configurations with the operable panel available in any position.

Sliding Window: A window in which the sashes move horizontally. Available in a 2- or 3-lite configurations.

Slope: The degree of roof incline expressed as the ratio of the rise, in inches, to the run, in feet.

Smooth-surfaced roofing: Roll roofing that is covered with ground talc or mica instead of granules (coated).

Soffit: Material used to enclose the horizontal underside of an eave, cornice, or overhang. Some soffit panels may also be used as vertical siding.

Soil stack: A vent pipe that penetrates the roof.

Solar Heat Gain Coefficient (SHGC): The fraction of solar radiation admitted through a window or skylight, both directly transmitted and absorbed and subsequently released inward. The solar heat gain coefficient has replaced the shading coefficient as the standard indicator of a window’s shading ability. It is expressed as a number between 0 and 1. The lower a window’s solar heat gain coefficient, the less solar heat it transmits and the greater its shading ability. SHGC can be expressed in terms of the glass alone or can refer to the entire window assembly.

Spacer: An object placed between two or more pieces of glass which helps to maintain a uniform width between the glass, and prevent sealant distortion.

Span: The horizontal distance from eaves to eaves.

Specialty eaves flashing membrane: A self-adhering, waterproofing shingle underlayment designed to protect against water infiltration due to ice dams or wind driven rain.

Square (Roofing): A unit of roof measure covering 100 square feet.

Square (Siding): A measurement of siding. One square equals 100 square feet (10 x 10 wall).

Square-tab shingles: Shingles on which tabs are all the same size and exposure.

SST non-metal 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.

Strapping: A flexible framing material used to even a surface prior to installation.

Starter Strip (Siding): An accessory applied directly to the surface of the building and used to secure the first course of siding to the home.

Starter strip (Roofing): Asphalt roofing applied at the eaves that provides protection by filling in the spaces under the cutouts and joints of the first course of shingles.

Steep slope application: Method of installing asphalt shingles on roof slopes greater than 21 inches per foot.

Step flashing: Flashing application method used where a vertical surface meets a sloping roof plane.

Strip shingles: Asphalt shingles that are approximately three times as long as they are wide.

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Tab: The exposed portion of strip shingles defined by cutouts.

Talc: See back surfacing.

Telegraphing: A shingle distortion that may arise when a new roof is applied over an uneven surface.

Three-dimensional shingles: See laminated shingles.

Three-tab shingle: The most popular type of asphalt shingle usually 12" x 36" in size with three tabs.

Top lap: That portion of the roofing covered by the succeeding course after installation.

TrueCapture™ Sloped Sill: The sill of some Alside double-hung windows that has a downward slope toward the outside with a capture dam that helps to keep water from infiltrating the base of the bottom sash. Sloped sill assists water drainage to the exterior of the window.

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UL label: Label displayed on packaging to indicate the level of fire and/or wind resistance of asphalt roofing.

Undereave: Underside area of the overhang at the eave of the roof.

Underlayment: A layer of asphalt saturated (sometimes referred to as tar paper) which is laid down on a bare deck before shingles are installed to provide additional protection for the deck.

Underlayment: Weather-resistant material placed under vinyl siding panels.

U-value (U-factor): A measure of the rate of non-solar heat loss or gain through a material or assembly. It is expressed in units of Btu/hr-sq ft-ºF (W/sq m-ºC). Values are normally given for NFRC/ASHRAE winter conditions of 0ºF (18º C) outdoor temperature, 70º F (21º C) indoor temperature, 15 mph wind and no solar load. The U-factor may be expressed for the glass alone or the entire window, which includes the effect of the frame and the spacer materials. The lower the U-factor, the greater a window’s resistance to heat flow and the better its insulating value.

UV (Ultraviolet light): The invisible rays of the spectrum that are outside of the visible spectrum at its short-wavelength violet end. Ultraviolet rays are found in everyday sunlight and can cause fading of paint finishes, carpets and fabrics.

UV reflection: The percentage of ultraviolet rays being blocked rather than being transmitted through the window’s glass unit. The higher the number, the lower the percentage of ultraviolet rays being transmitted through the window.

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Valley: The internal angle formed by the intersection of two sloping roof planes to provide water runoff.

Vapor retarder: Any material used to prevent the passage of water vapor. Material which, when installed on the high vapor pressure (warm in winter) side of a material, retards the passage of moisture vapor to the lower pressure (cold in winter) side. Note exception: Florida and Gulf Coast. Check local building codes to determine what side the vapor retarder should be placed.

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 sleeve: See collar.

Ventilators: Devices that eject stale air and circulates fresh air (i.e., ridge, roof, gable, undereave, foundation or rafter vents and vented soffit panels.)

Visible Light: The portion of the electromagnetic spectrum that produces light that can be seen. Wavelengths range from 380 to 720 nanometers.

Visible transmittance (VT) The percentage or fraction of the visible spectrum (380 to 720 nanometers) weighted by the sensitivity of the eye that is transmitted through the glazing.

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Warm-edge technology: The use of low-conductance spacers to reduce heat transfer near the edge of insulated glazing.

Weather-stripping: Material used to form a weather-resistant seal around operable sash.

Weep Holes: Openings cut into siding or accessories to allow for water runoff.

Woven Valley: Method of valley construction in which shingles from both sides of the valley extend across the valley and are woven together by overlapping alternate courses as they are applied. The valley flashing is not exposed.