are about equally suitable for flooring. However, in the consideration of color and grain there is a notable distinction. In general. white-oak flooring is light in color with a brownish tinge, while red oak, although also light in color, has a natural pink cast which usually turns to a reddish brown under finishes commonly applied to flooring. Both white and red oak are ring-porous woods-which means that there are larger, more prominent pores in the springwood of each year's growth than in the summerwood. This fact accounts for the characteristic figure prominent in plain sawn-oak flooring. However, the pores of white-oak heartwood are usually plugged with a minute bubble-like growth called tyloses which make the grain less open than in red oak.

Both white and red oak also are characterized by prominent wood rays, which are strips of cells extending radially in the tree, sometimes 4 inches or more in height. When quarter-sawed flooring is produced these wood rays are frequently cut through so as to expose a large flake figure on the surface, often seen on oak furniture. Thus, both white and red oak flooring is procurable in quarter-sawed grain.

MAPLE

Most of the maple flooring is produced from hard maple trees. There are but two species of maple jointly classed as hard maple, although, as is the case with other species, there are several common local names such as sugar maple, sugar tree, rock maple, and black maple.

The heartwood of hard maple is light reddish brown, whereas the sapwood is white with a slight reddish-brown tinge. Thus, certain grades of maple flooring are available in a specific color.

Hard maple is very hard, heavy, and strong and wears exceptionally well under abrasion. The wood is diffuse-porous (which means that there are no prominent springwood pores), the minute, evenly scattered pores resulting in a fine-textured or close-grained wood. Since there are no prominent wood rays, maple is not produced in quarter-sawed flooring. In some instances curly or bird's-eye figured maple logs are cut into flooring and sold as a special grade.

BIRCH

Birch flooring is produced from two species known as yellow birch and sweet birch. The wood is hard, heavy, and strong and has good resistance to abrasion. Similar to maple, it is fine and uniform in texture, being a diffuse-porous wood. The heartwood is generally of a light reddish-brown color and the sapwood very much lighter. Certain grades of birch flooring are selected for color.

BEECH

Few trees are so easily identified by the novice woodsman as the beech, which because of its smooth, gray bark entices many people to carve their initials on the trunk of the tree. The wood is hard, strong, and heavy and, being diffuse-porous, is of uniform texture. It wears well under abrasion. Although beech is a wood having a rather prominent wood ray, it is not manufactured into quarter

sawed flooring because the resulting figure is not sufficiently attractive. Beech flooring is available in a special grade selected for color.

TYPES OF AMERICAN HARDWOOD FLOORING

The style of architecture is an important factor in determining the type or types of flooring which would be most suitable for a particular building. Of course, the architect or builder must also give proper consideration to the item of cost, a matter easily solved by the several grades and types of hardwood flooring available. Changing architectural styles, changing construction methods, and the public's everactive desire for the "new" and "modern" naturally demanded hardwood floors in new and different forms, which the industry has been

residences.

quick to supply. A suitable type of hardwood floor is readily available for practically any architectural or interior-decoration specification. While it is impossible to describe in words, or even show by pictures, the true beauty and character of the numerous styles and patterns of hardwood floors available, the following brief summary may assist in a general appraisal.

STRIP FLOORING

The type of hardwood flooring most extensively used is strip flooring. The fact that it is so widely used does not, however, make it "commonplace" in the true sense of the word, because no two hardwood floors are ever exactly alike in character and beauty of grain. Furthermore, it is a simple matter to obtain interesting patterns in ordinary strip flooring by using a random mixture of widths, or a variation of stock selected for color, thus achieving, in effect, a form

of patterned floor. Besides character of grain, there is the important factor of "character markings" found in hardwoods which may be small, tight knots (oftentimes cut at an angle), mineral streaks, or other natural irregularities in the wood. While such irregularities are not allowed in the highest grades of hardwood flooring, they lend distinction to floors in which they appear.

Strip flooring obtains its name from the narrowness of the pieces of which the most frequent width is 214 inches. Other sizes range from 12 to 311⁄2 inches wide. Most strip flooring is almost an inch thick, although other thicknesses ranging from three-eighths to about 15% inches are available. (See p. 18 for details of grades and sizes.) The thinner types are used primarily for remodeling where the desirable appearance and qualities of hardwood floors are wanted but where it is not expedient to reduce room height or go to the expense of thicker flooring.

PLANK FLOORING

Plank flooring is one of the older types of floors. It is this pattern which gives a mark of distinction to our American colonial homes. In the past 10 years, the demand for plank flooring has greatly increased. It can be obtained in any desired quantity or in practically any of the hardwood flooring species at very reasonable

cost.

Plank floors go back to the hand-craft era, when floors and other interior trim were the product of individual craftsmen. The rough effects and interesting irregularities of flooring of the times were not intentional but were a result of material manufactured by hand. The plank floors of today are manufactured on modern machines. However, they retain the appearance and beauty and irregularities of the original types. They are usually of random width. Frequently the edges of the pieces are "eased" or rounded to give the effect of large cracks which were characteristic of the old-fashioned hand-hewn plank floor. Plank flooring is blind-nailed (i. e., toenailed on the edges, so that the head of the nail is covered by the edge of the adjoining piece). In addition to blind nailing, the planks are fastened on the ends and at the intermediate intervals with screws through the face of the material. The screws are countersunk and wood plugs are glued in the holes, thus simulating the effect of the old-fashioned wood pegs, which was the usual method of fastening the plank flooring of bygone days. Plank flooring may be obtained in most species in the clear grade (with barely perceptible character marks) or in other grades with more outstanding character marks, which give the floor a very rugged appearance.

PATTERNED FLOORS

In the field of patterned floors (also often referred to as parquetry or design floors), hardwood has come to play a dominant part. The use of patterned hardwood floorings is by no means new, and it is believed their appearance dates as far back as the fourteenth century. The bizarre effects of the early classic designs did not lend themselves to the later architectural styles, so modern patterned hardwood floors are now of a type much simpler, usually a geometric pattern such as

a square, rectangle, or sometimes herringbone. In many of the fine old homes of England and France can be seen fine examples of beautiful hardwood patterned floors which have given service for scores of years. They blend perfectly with the masterpieces in painting and sculpture and the architecture found in such buildings.

Today, in this country, many types of patterned floors are being manufactured. Quite frequently these patterned floors are referred to as parquetry, which may be defined as a type of wood mosaic. Parquetry is manufactured in short lengths of individual pieces which are often laid in square blocks or irregular patterns of certain design or sometimes in herringbone design. In manufacturing parquetry floor strips each individual piece must be carefully cut to an exact dimension so that when put together the width of the block will perfectly match the length of a single piece or a multiple thereof. The individual pieces are nailed or set in mastic separately.

Figure 9.-Laying block hardwood floors in mastic. Floors of this type are found to be both beautiful and practical.

Another form of parquetry flooring is the prefabricated block. In manufacturing this type, the individual pieces are assembled in square or rectangular blocks at the factory and fastened on the back, or at ends, with a metal spline or other type of fastener. The blocks are accurately squared and often prefinished at the factory so they are ready to be laid as a floor. Such blocks can be either nailed or set in mastic.

Patterned flooring material can be obtained in practically any suitable hardwood species. Beautiful and variable effects may be had by using a species of light-colored hardwood alternated with a species of dark-colored hardwood, or perhaps light and dark blocks of the same species alternated. The possibilities of variation in design are almost unlimited. Practically any type of architecture can be complemented with patterned flooring.

Other types of patterned flooring are also being manufactured. Whereas the block or rectangular type just described is usually thirteen-sixteenths or twenty-five thirty-seconds inch thick, there are

other types which are made up of thin pieces of wood glued to a flexible back-having, as their recommendation, economy of material

and ease of installation.

ORGANIZATION OF HARDWOOD FLOORING INDUSTRY

Wood is a natural material, and one of the factors which has made it so useful to man is the quality which allows it to be easily worked to desirable sizes and shapes. Wood also has the quality of being able to withstand a great deal of abuse without being made totally unfit for use. These qualities, while of great value, have been (as is to be expected) taken advantage of sometimes in such a way as to bring discredit to one of the finest construction materials known to man. Wood, like any other material, should be handled with intelligence and manufactured into usable commodities only by persons or firms possessing the knowledge and equipment to use it correctly. This is particularly true in respect to hardwood flooring which is destined for use in all types of buildings where fine appearance and unusual wearing qualities are of major import.

In order to provide the public with suitable hardwood flooring and to protect the industry from unscrupulous exploitation, a large number of flooring manufacturers have pooled their knowledge and experience in formulating grading rules and recommending the best manufacturing practices. The authority and machinery for handling these matters have been invested in trade associations. Today there are two hardwood flooring associations of major importance. These two associations have provided the United States and the world with uniform grading rules and commercial standard practices for the manufacture and sale of hardwood flooring.

MAPLE FLOORING MANUFACTURERS' ASSOCIATION

The office of this association is located at 332 South Michigan Avenue, Chicago, Ill. Its primary function is to establish and enforce uniform grades and standards of products, supplying its members with grading rules, grade-inspection service, manufacturing standards, and other useful information. Reinspection service is provided under certain conditions when complaints on the product arise. To the consumer it provides information regarding the purchase, laying, finishing, and refinishing of the products. The members of the association are permitted to use the standard trade mark of the association (MFMA), and when the flooring is so stamped by an authorized manufacturer the association guarantees to the consumer that the product is of proper standard and grade.

The right and license to use the association's trade mark is given only to members of the association. In addition, members are authorized to issue association certificates of inspection, constituting an additional guaranty to the customer as to the correct species, size, grade, accurate tally, and millwork of the flooring. Members are required to grade-mark and species-mark their flooring.

The Maple Flooring Manufacturers' Association has its membership confined to manufacturers in the Northern States and provides the foregoing services for northern hard maple flooring, northern beech flooring, and northern birch flooring.