Siding Glossary

This glossary includes words that are the language and jargon of the siding industry.  To avoid confusion, we thought it a good idea to share our understanding of each of these terms with you.

Bead This architectural term refers to a narrow, half-round molding at the base of the panel.

Casing Molding of various widths used to trim door and window openings at the jambs. Also referred to as lineal, window, and door surround.

Chalking White residue visible on face of panels as they weather.

Clapboard This architectural term refers to a thin, narrow wood board with one edge thicker than the other and used as siding. Vinyl siding clapboards are designed to replicate this wood style.

Cornice The overhang of a pitched roof at the eave line, usually consisting of a fascia board, a soffit for a closed cornice, and appropriate moldings.

Die A device of stainless steel used to shape vinyl siding and accessories.

Dutchlap This architectural term refers to a drop-style panel that was popularized by early American settlers in the seaboard states.

Embossing Woodgrain pattern rolled or formed into the face of the panel or accessories to create a wood like appearance.

Expansion and Contraction Commonly refers to panel expanding when heated up or contracting when panel is cooled down, especially as outside temperature changes.

Extruder Machine that converts raw PVC compound to molten plastic and forces it through a die.

Exposure The width of each panel of siding. Also referred to as reveal.

Face Nailing Nailing through siding where no provision is made for nail slots.

Fascia An architectural term referring to a flat, horizontal band. In the vinyl business, it refers to the wide trim that runs along the roof line.

Finish Refers to the texture (and sometimes the gloss level) of a vinyl siding panel.

Frieze The horizontal member connecting the top of the siding with the soffit.

Gable In house construction, the portion of the roof above the eave line of a double-sloped roof.

Gloss Term used to describe amount of reflection or sheen on the surface of a panel.

Insulated Siding Panels reinforced with insulating materials, typically 1-in. thick polystyrene.

Lap Where two siding panels join horizontally.

Lineal Molding of various widths used to trim door and window openings at the jambs. Also referred to as casing, window, and door surround.

Lock Where two siding panels join or lock together vertically.

Nail Hem The top edge of a panel of siding. The siding is hung
from the nail hem.

Oil Can A distortion in the siding panel.

Panel Projection The distance that vinyl siding projects from the wall. As a rule of thumb, a larger panel projection creates a more pronounced shadow line and a stiffer panel.

Profile Side view of a vinyl siding panel.

PVC Polyvinyl chloride, the plastic resin used to manufacture “vinyl” siding.

Rake Trim members that run parallel to the roof slope and form the finish between the wall and a gable roof extension.

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.

Soffit The underside of an overhanging cornice.

Square Unit of measure for siding equal to 100 square feet of exposure (or a 10-ft. by 10-ft. wall section).