Siding Terminology

Siding terminology

Backer Tab: 
Supports non-insulated 8" siding at the panel overlaps or joints, and also behind panels on corners to make certain of a smooth installation.
 


Butt Edge: 
The bottom edge of siding or a soffit or an accessory piece. It locks onto the previous panel.
 


Channel: 
Area where the siding/soffit panels are inserted. This is also referred to trim itself and is named according to a letter it resembles (C-channel, J-channel).

 
Course: 
The row of panels, one panel wide, spans the length of the building from one side to the other or if using vertical siding, from top to bottom. 


D4 Profile:
Two four-inch wide horizontal conventional planks for each single panel of siding. 

D5 Profile: 
Two five-inch wide horizontal conventional planks for each single panel of siding.
 


Drip Cap/Head Flashing: 
This is used on vertical siding to make certain that water drips away from panels and does not penetrate them; This is used as a vertical base.
 


Dutchlap or Shiplap: 
A decorative variation on clapboard styling. The face of the board is beveled. 

Eaves: 
The underside of the roof overhanging a wall. 

F Molding (or Trim): 
Trim molding which is in the shape of a letter F, typically used from soffit trim on the wall side above the vinyl siding.
 


Face: 
The visible part of the siding when it is installed.

 
Face Nailing: 
This is the action of nailing directly into the face of a panel. This is generally not used in siding installation. 


Fascia: 
The trim piece nailed to the rafters or trusses tying them together and the lower level ending of the roof. This is the front edge of the soffit.


Fascia Board: 
The exterior finish which is nailed to the fascia that is nailed to the rafters or truss ends. This forms a drip edge for the rain water and hide the edges of the soffit and roof sheathing. 


Flashing: 
This is a sheet, usually of metal such as aluminum which is used at intersections of components to prevent water penetration. Usually used around doors and windows to prevent water from getting behind the siding.

 
F-channel: 
A component of vinyl or aluminum siding systems which have a channel which the planks fit into. This is typically used around windows and doors to prevent water penetration.
 


Furring Strip: 
Used to provide an even nailing base. In most cases, a wooden or steel framing material, typically 1" x 3". 


Gable: 
This is the upper triangle-shaped part of the end wall of the house.


Inside Corner Post:
Provides joining at inside corners where siding butts both sides. 


J-Channel: 
Molding used as trims and is in the shape of a letter J. Used to trim edges of siding at the windows, doors, gables, or any other various places. 


Lap: 
Overlapping the ends of two siding panels to allow for expansion and contraction of the siding product. 


Lap Siding: 
A technique used for installing horizontal siding- each piece of siding is overlapped on to the piece below it. This insures water protection.
 


Nailing Hem: 
also known as a Flange- is the section of siding or accessories where the nailing slots are located.
 


Outside Corner Post: 
These are used to provide clean appearance on the outside corners for both vertical and horizontal siding. The deeper posts are for insulated siding and narrow posts are for non insulated.
 


Positive Lock: 
Ensures panels can be locked together, but can also slide to ease the install. This also ensures the install is prepared for extreme weathers.
 


Plumb: 
Is the complete vertical, 90 degree from a level surface.
 


Profiles: 
This is the actual siding panel. Some commonly sized profiles are D4, D5 and Dutchlap.
 


PVC: 
PVC (Polyvinyl chloride) is the common material used to create most vinyl siding. 


Rake: 
The part or edge of a slope roof which forms the overhang beyond the wall.
 


Soffit: 
The underside of exterior elements on a building such as the overhang, beams and staircases.
 


Square: 
Is a unit of measurement, a square is equal to 100 square feet or 10ft x 10ft.
 


Square Feet: 
Exterior Square Feet is a phrase used to indicate the total amount of siding material required for a particular siding job together with material waste.


Starter Strip: 
This is a baseline accessory used to secure the first course of siding to the wall, used either for horizontal or vertical siding. 


Tongue and Groove (T&G): 
A connection system between components, such as wood, in which the tab( known as the  tongue) of one board is placed into the grove at the end of a different board
 


Wall Cladding : 
The term used for siding.
 


Wall Sheathing: 
The sheets of plywood or wood plank which cover the studs or framework of the house. This is what the siding attaches to.


Weep Holes: 
The small hole on the bottom butt edge of vinyl siding which allows condensation to run off.
 


Windload Pressure: 
The measure of how a panel would withstand winds.
 


Window Head Flashing: 
Alternative to J-channel of receiving siding over doors windows and as base flashing for vertical siding installs.