| Value-Added Product | Or Value-Added Production. Adding value to a product by further processing it. Examples of value-added wood products include joinery stock, windows, doors, kitchen cabinets, flooring and mouldings. |
| van der Waal Forces | Physical forces of attraction between molecules, which include permanent dipole, induced dipole, hydrogen bond, and London dispersion forces. |
| Vapor Retarder | A material with a high resistance to vapor movement, such as foil, plastic film, or specially coated paper, that is used in combination with insulation to control condensation. |
| Vapour Barrier | The element in a wall, floor or ceiling that does not allow moisture or air to penetrate and is used to prevent condensation in insulation. |
| Vegetated Filter Strips | Use vegetation to filter sediment and pollutants form stormwater. Best used in areas of low volumes and low velocity run off. Often used as pre-treatment for other systems but can provide some subsurface infiltration. Swales comprise an open trench or ditch and need mowing. Also known as grassy swales. |
| Veneer | A thin layer or sheet of wood. |
| Veneer, Rotary-Cut | Veneer cut in a lathe that rotates a log or bolt, chucked in the center, against a knife. |
| Veneer, Sawn | Veneer produced by sawing. |
| Veneer, Sliced | Veneer that is sliced off a log, bolt, or flitch with a knife. |
| Vermiculite | A hydrous silicate of magnesium or iron which is expanded by heating to produce a lightweight fire resistant insulation. |
| Vertical-Grained Lumber Grain | Another term for edge-grained lumber. |
| Vertically Laminated Timbers | Laminated timbers designed to resist bending loads applied parallel to the wide faces of the laminations. |
| Vessel Elements | Wood cells in hardwoods of comparatively large diameter that have open ends and are set one above the other to form continuous tubes called vessels. The openings of the vessels on the surface of a piece of wood are usually referred to as pores. |
| Virgin Growth | The growth of mature trees in the original forests. |
| Viscoelasticity | The ability of a material to simultaneously exhibit viscous and elastic responses to deformation. |
| Viscosity | The ratio of the shear stress existing between laminae of moving fluid and the rate of shear between these laminae. |
| Volatile Organic Compounds (VOCs) | Carbon compounds that participate in atmospheric photochemical reactions (excluding carbon monoxide, carbon dioxide, carbonic acid, metallic carbides and carbonates, and ammonium carbonate). The compounds vaporize (become a gas) at normal room temperatures. |