Glossary
Siding Terms
Backer Tab
Provides support for non-insulated 8" siding at panel overlaps (joints), and behind panels at corners to ensure a smooth installation.
Butt Edge
Bottom edge of siding/soffit panel or accessory piece opposite the nailing slots. Locks onto the preceding panel.
Channel
Area of accessory trim or corner post where siding/soffit panels are inserted. Also refers to trim itself, and named according to letter of alphabet it resembles (i.e., J-channel, F-channel, etc.).
Course
Row of panels running the length of the house.
Face
Side of siding/soffit panel that is showing once panel has been installed.
Face Nailing
Action of fastening directly onto the face of panel, rather than using the nail hem slot. Generally not used in siding installation.
Fascia
Vertical finishing edge usually fastened to ends of rafters or trusses. Most commonly found where the gutter is attached.
Flashing
Thin, flat material - usually aluminum - positioned under or behind J-channels, corner posts, windows, etc., to keep water drainage from penetrating house.
Individual Outside Corner Cap
Possible alternative to outside corner post when installing 8" horizontal siding. Maintains continuity of siding courses in traditional clapboard style.
Inside Corner Post
Provides a means of joining at inside corners where siding butts both sides. Deeper posts are for insulated siding, and narrower posts for non-insulated siding.
Insulated Siding
Available with factory-laminated polystyrene backing. In addition, separate drop-in backer board is available which can be combined with the siding panels at the time of installation. Laminated and drop-in backer board thickness vary from 3/8" to 1/2", and can be used with 8", Double 4" or Double 5" siding.
J-Channel
Used for receiving siding on all sides of windows and doors, at rake edges of gables and in other miscellaneous situations. Deeper J-channels are for insulated siding, and narrower J-channels for non-insulated siding.
Lap
To overlap ends of two siding panels to allow for expansion and contraction of siding product.
Lug/Crimp
Raised tabs on siding panel created by a snap-lock punch. Can be used to lock siding panel into place when the nailing hem has been removed.
Mitre Cut
Diagonal cut, beveled to a specific angle (usually 45). Sometimes applied to an overlapping siding or soffit panel surface for a neater appearance.
Nailing Hem (Flange)
Location of nailing slots on siding panel or accessories.
Outside Corner Post
Provides neat appearance outside corners for vertical and horizontal sidings. Receives siding from both sides. Deeper post is used with insulated siding, and narrower post with non-insulated siding.
Snap-Lock Finish Trim
Used to finish off (trim) job-site cuts on siding, as under windows, at eaves, and at porch door locations. May also be used to receive vertical siding at corners and window jambs. The snap-lock design allows siding to be notched and locked into place without face nailing.
Soffit
Vinyl or aluminum material used on the underside of eaves between the exterior wall and overhanging edge of the roof rafters.
Starter Strip
Baseline accessory which secures the first course of siding to the wall. Used with horizontal and vertical siding.
Trim Coil
Painted aluminum and steel material commonly used to case around windows. Allows remodeler to totally enclose house.
Underlayment
Weather-resistant material placed under siding panels.
Weep Holes
Openings cut into siding or accessories to allow water runoff.
Window Head Flashing
Possible alternative to J-channel to receive siding over doors and windows and as a base flashing on vertical siding installations.
Profiles
Beaded
Authentic 17th century horizontal Colonial beaded ridge in a 6.5" design with graceful shadow lines.
Double 4 Clapboard
Classic horizontal 8" wide design with stepped 4" beveled boards and bold shadow lines.
Double 5 Clapboard
Similar to Double 4 Clapboard profile, but wider 10" face exposure with stepped 5" beveled boards.
Double 4.5 Dutch Lap
Similar to Double 4 Dutch Lap, but wider 9" face exposure with stepped 4.5" sculpted boards.
Double 4 Dutch Lap
Traditional horizontal 8" design with stepped 4" sculpted boards to maximize horizontal shadow lines.
Double 5 Dutch Lap
Similar to Double 4 Dutch Lap, but 10" face exposure with stepped 5" sculpted boards.
Single 8 Clapboard
Traditional horizontal 8" wide design, beveled from top to bottom.
Triple 3 Clapboard
Victorian-style horizontal 9" wide design with three stepped-down 3" beveled boards.
Vertical Board & Batten
Vertical siding with deep shadow lines created with raised batten strips.
Vertical V
7" vertical siding replicating tongue-and-groove construction.
Finishes
Fluropon
Specially formulated KYNAR 500/HYLAR 5000* based coating that provides superior resistance to staining, mildew and dirt.
LoMar Polyester
Soft, low-luster satin finish with excellent resistance to surface marring and scuffing.
PVC
Premium semigloss (polyvinyl chloride) finish that's several times thicker than ordinary coatings and provides excellent resistance to surface wear and abrasion.
*Fluropon is a registered trademark of The Valspar Corporation.
KYNAR 500 is a registered trademark of ELF Atochem North America, Inc.
HYLAR 5000 is a trademark of Ausimont USA, Inc.
Window Terms
Daylight Transmittance
Measures the amount of visible light that is transmitted thr
Fenestration
An architectural term referring to the arrangement of windows in a wall. From the Latin word "fenestra" meaning window.
Frame
The enclosure in which window sashes or door panels are mounted.
Glazing
The act or process of fitting a window or door with glass.
Insulated Glass (IG)
A combination of two or more panes of glass with hermetically sealed air space between. This space may be filled with an inert gas, such as argon.
Low-Emissivity (Low-E) Glass
A special type of glass having a microscopically thin metallic layer vacuum deposited into its surface that acts as a thermal mirror. In the summer, Low-E glass lets in visible sunlight while minimizing infrared and ultraviolet solar energy that can increase cooling costs and cause curtains, carpets and furniture to fade. In the winter, Low-E glass helps reduce heating costs by reflecting indoor heat back into the room.
R-Value
Represents a material's resistance to heat flow and its ability to insulate. The higher the R-value, the better insulation performance.
Sash
A single assembly of stiles and rails made into a frame for holding glass.
Stile
The main vertical members of the framework of a sash.
U-Factor (also referred to as U-value)
The rate of heat flow through a glazing system. The lower the value, the better the insulating quality. U-value can be compared to R-value by dividing 1 by the U-value. For example, a U-value of 0.5 equals an R-value of 2.
UV Block
Measures the amount of damaging ultraviolet light that is blocked from being transmitted through the glass.
