U-Z
Undercourse:
Low grade (usually #4) shingles used as the initial layer of material on a double-coursed sidewall of a building.
V:
Any of several longitudinal cuts made on the faces of pieces of lumber or plywood. The face veneer of plywood paneling is V-grooved to relieve the flat appearance of the surface; the grooving usually creates a pattern resembling random width boards placed side by side. Usually, V grooves in paneling are stained darker than the surface. In lumber, edges are sometimes chamfered to create a V where pieces are placed edge to edge. A V may also be machined the length of the piece to provide decoration. A V pattern also may be used to form tongue and groove connections on either lumber or plywood.
Vapor Barrier:
Material placed on the warm side of a wall to prevent the movement of vapor through the wall. A plastic or paper sheet, or paint.
Veneer:
A thin sheet of wood, rotary cut, sliced, or sawn from a log or flitch. Veneering goes back to the early days of the Egyptians, which would be approximately 3,500 years ago. Down through the years and cultures veneering has enriched furniture and architectural interiors with sheets of rare and beautiful woods bonded to other plain, sturdy wood based sub straights to form a panel.
Vertical Grain (VG):
Lumber that is sawn at approximately right angles to the annual growth rings so that the rings form an angle of 45 degrees or more with the surface of the piece.
Wainscot:
A lower interior wall surface (usually extending three to four feet up from the floor) that contrasts with the wall surface above it; an interior wall composed of two different interior wall surfaces, one above the other.
Wane:
Bark, or the lack of wood from any cause, on the edge or corner of a piece of lumber. In plywood, thin to open areas in veneer sheets that result from outer log surface irregularities.
Warp:
Any variation from a true or plane surface, including bow, crook, cup, or any combination of these.
Western Red Cedar:
Thuja plicata. This species is found principally along the western edges of British Columbia, Washington and Oregon. The wood is soft, straight-grained, and extremely resistant to decay and insect damage. It is used extensively in roof coverings, exterior sidings, fences, decks, and other outdoor applications.
Worm Holes:
Holes resulting from infestation of worms.
Z Flashing:
Z-shaped metal flashing applied between panels of plywood siding to shed water.