Design Solutions - Spring 2008 - (Page 52) How to Select Solid Lumber The Language of WoodWorking The language of the woodwork industry is not complex or too technical, but it does have some “traditional” terms which may seem confusing at first. AWI’s 8th edition Quality Standards Illustrated (QSI) contains descriptions of a few selected species of wood starting on page 18. The common names are followed by the botanical names. When a vendor suggests a species not on this list, ask for the botanical name as well as the common name. If there are any questions about the character of the wood, both the common name and the botanical name can be used to find information. Eight factors influence lumber selection: aesthetics, availability, size limitations, cost, strength (including hardness and density), dimensional stability, adaptability for exterior use, and fire rating. These factors are explored at length in the Quality Standards in Sections 100-G-2 and following. Aesthetics includes such factors as color, grain, figure, and finishing characteristics. Raw lumber is not classified as AWI Custom, Premium, or Economy Grade. Only finished products carry an AWI Grade designation. One of the qualities that contributes to the widespread use of wood is the option offered for aesthetic selection. It varies between species, between two logs of the same species, and even between two boards from the same log. Two of the most common mistakes made by project specification writers involve Birch and Maple. While most specifiers have “select white” in mind, they fail to call for it in the Contract Documents. As a result natural Maple or natural Birch is often supplied, with all the variations in color characteristic of the natural versions of the species. Select white Birch or Maple comes from the sapwood of the tree. Always remember there is no such thing as clear lumber. Specifications calling for “clear” lumber are always open to interpretation. All wood has natural characteristics. What’s clear to one person is often not acceptable to another. Plain Sawn - ±0°-30° Tangential grain Radial grain Quarter Sawn - ±60°-90° “Rift” Characteristics - ±30°-60° (oak) Page 22, Quality Standards Ilustrated AWI’s Quality Standards incorporate a glossary of natural characteristics, to help you understand what is meant by terms such as burl, check, or sapwood (page 27). In the 8th Edition are clarifications of the terms “compatible for color and/or grain” and “well matched for color and/ or grain.” As the Quality Standards points out, these terms are subjective. Two terms that are often confusing are “hardwood” and “softwood.” With only a few exceptions, not usually used in fine woodworking, the distinctions are easy to remember. Hardwoods are usually broad-leafed trees which lose their leaves in winter. Softwoods are usually needled trees which stay green all year. The most important thing to remember is that the terms have nothing to do with the density (that is to say, the hardness) of the wood. For example, Southern yellow Pine is a very hard softwood. Often used for stair treads and flooring, it can usually be recognized when compared with other “Pines” by its light and dark figure. Most fine furniture and architectural woodwork is made from a relatively small group of hardwoods. Domestic hardwood forests have been well managed for the past 90 years. Our inventory of standing hardwood in North America is about 30% larger now than it was in 1930. Of all the building materials you specify, wood is the only natural resource which renews itself, making more available for future generations. The other common ingredients of building construction are finite resources, never to be renewed. Think of concrete, steel, aluminum and glass. They all come from digging in the earth, they require large amounts of energy to process and fabricate; and, once extracted, are forever gone. 52 DESIGN SOLUTIONS I Spring 2008
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