Planning a Hardwood Floor

A good job begins with good planning. This adage is especially true for installing and maintaining hardwood floors. Many installation problems can be solved on paper before the work begins, which saves time and materials. In this section, you’ll learn how to plan and prepare for your hardwood flooring project by selecting the correct materials, properly choosing and using tools and fasteners, and learning how hardwood flooring can effectively be used in your home.


Figure 2-1 illustrates a floor or building plan. In home construction, the floor plan guides the contractor and subcontractors in the erection of walls, floors, and roof. Information found on a floor plan includes the lengths, thicknesses, and character of the building walls on each particular floor; the widths and locations of door and window openings; the lengths and character of partitions; the number and arrangement of rooms; and the types and locations of utility installations. In many cases, the floor plan will also establish the type and layout of the flooring.

Fig. 2-1 Typical home floor plan or building plan.

A floor plan of your home can be valuable to you when you estimate, plan, and install hardwood flooring. You may have a floor plan for your home from the contractor or from an appraiser, or you may have to generate one yourself with a tape measure and some graph paper. In either case, you’ll find the time spent on researching your home’s floor plan a worth while investment as your hardwood flooring project continues.


Hardwood flooring is lumber. You may also need to use other types of structural lumber as you install and repair your hardwood floor, such as subflooring, floor joists, sole plates, wall studs, and headers. Let’s consider the planning and selection of lumber.

Lumber is usually sawed into standard sizes, which are described in length, width, and thickness measurements. This permits uniformity when structures are planned and materials ordered. TABLE 2 lists the common widths and thicknesses of wood in rough, or nominated, and dressed dimensions in the United States. Standards have been established for dimension differences between the quoted size of the lumber and its standard sizes after it is dressed. Quoted sizes refer to the dimensions of the wood before it is surfaced. These differences must be taken into consideration.

A good example of the dimension difference is the common 2 x 4. As you can see in the table, the familiar quoted size of 2 x4 is the rough or nominated dimension, while the actual dressed size is 1 5/8 x 3 5/8 inches.

Lumber, as it comes from the sawmill, is divided into three main classes: yard lumber, structural material, and factory and shop lumber. Yard lumber is that used for ordinary construction and general building purposes. It is subdivided into the classifications of select lumber and common lumber.

Select lumber is of good appearance and finish. It is identified by the following grade names: grade A, grade B, grade C, and grade D.

Common lumber is suitable for general construction and utility purposes. It has the following grade names: No. 1 common, No. 2 common, No. 3 common, No. 4 common, and No. 5 common.

Softwood flooring is graded as select: A, B, C, and D. First-grade softwood flooring is B or better; second-grade is C or better.

Hardwood flooring is graded as Clear, Select, then No. 1 common, etc. Some types of hardwood will be graded as first-grade, second-grade, etc.

Table 2-1 Nominal and Standard Lumber Sizes


The sizes of lumber and woods are standardized for ordering and handling convenience, Building and finish material sizes run 8, 10, 12, 14, 16, 18, and 20 feet in length; 2, 4, 6, 8, 10, and 12 inches in width; and 1, 2, and 4 inches in thickness. The actual width and thickness of the dressed lumber are considerably less than the standard, or quoted, width and thickness. Hardwoods, which have no standard lengths or widths, run 1/4, 1/2, 1, 1 1/4, 1 1/2, 2, 2 1/2, 3, and 4 inches in thickness.

Plywoods are usually 4 x 8 feet and vary in thickness from 1/ to 1 inch. Stock panels are usually available in widths of 48 inches, Lengths varying by multiples of 16 inches up to 8 feet. Panel lengths run in 16-inch multiples because the accepted spacing for studs and joists is 16 inches.

The amount of lumber required for a job is measured in board feet. A board foot is a unit of measure that represents an area of 1 square foot and a thickness of 1 inch actual or nominal size. The number of board feet in a piece of lumber can be computed by the arithmetic method or by using a table.

To determine the number of board feet in one or more pieces of lumber, the following formula is used:

(pieces x thickness x width x length) / 12

In the equation above, the thickness and width are expressed in inches and the length in feet. As an example, here’s how to find the number of board feet in a piece of lumber that is 2 inches thick, 10 inches wide, and 6 feet long:

1 x 2 x 10 x 6 / 12

= 10 board feet

Rapid estimations of board feet can also be made using TABLES 2-2 or 2-3.

Table 2-2 Rapid Calculation of Board Measure

Table 2-3 Board Feet


As with most consumer products, how you purchase can be as important to the job as what you purchase. If you buy inferior hardwood flooring and don’t select a retailer who will stand behind what is sold, you can’t expect a superior-quality floor.

An important and often overlooked fact is that when you buy any product, you also are buying whatever support service the retailer offers.

At the big chain store that has some hardwood flooring on sale, you will probably know more about the product you buy than will the clerk who sells it to you. Unless you are an expert in the product you are selecting, avoid such retailers. You will be farther ahead if you buy from a retailer who can support his merchandise with product knowledge and assistance

How can you purchase hardwood flooring from specialized retailers and still get a good price? First, select a retailer from whom you would feel comfortable buying if you had more money. Then let them know that you don’t have to buy it immediately and that you would prefer to wait until you could earn a savings of 25% or more. Most retailers understand and will either work out some type of discount nearing or surpassing this figure, or will suggest when that price discount will be available.

To make the best purchase, you must be sure that there are no hidden costs and know exactly what is included with your purchase. Once you know which type of hardwood flooring to select, how it will be installed, and approximately how much you will need, make a list of the components you will need to buy—flooring, fasteners, adhesives, tools, finishes, and special equipment rentals. Then you can make sure that the total price really is the total.

You also need to know what you’re buying. You should know the characteristics of wood and understand the different types of joints and flooring patterns. This information is offered here. Later in this section, you will find out about tools and fasteners. Read about them before you go on your shopping trip.

One method that is used by smart consumers to ensure that what they bought is what they thought they bought is to defer partial payment. Make arrangements to pay part of the bill when the order comes in, part on delivery after an inspection and inventory, and the final amount 30 days after delivery. The flooring retailer who often works with local con tractors is accustomed to such terms. These terms offer you the opportunity to verify the quantity and quality of the hardwood flooring and related materials with recourse.

Remember that a bargain is only a bargain when the job is complete. What may have initially cost less to purchase may eventually cost more. One of the reasons you are doing it yourself is to save money. By purchasing your hardwood flooring as a smart consumer, you will save money and have a better quality floor when you’re done.


There are a variety of hand and power tools available to the do-it yourselfer who wants to install hardwood flooring inexpensively and efficiently Figure 2-2 illustrates the basic tools that are suggested by one hardwood-flooring manufacturer. They include a handsaw or power saw, hammer, crowbar, square, chalk line, wedge, adhesive, and a special installation tool.

Fig 2-2 Typical tools needed for hardwood flooring installation.

One of the most important tools for a hardwood-floor installation is the measuring tool. The ability to accurately lay out and measure a room depends on the correct use of the measuring tools and the ease with which the graduations on the tools can be read. While each measuring tool is used for a specific purpose, they are all graduated according to the same system of linear measure.

Figure 2-3 shows the types of rules and tapes that are commonly used by builders and do-it-yourselfers. Of all the measuring tools, one of the most practical is the steel rule. This rule is usually 6 or 12 inches in length. Steel rules may be flexible or inflexible, but the thinner the rule, the easier it is to measure accurately because the division marks are closer to the work.

Fig 2-3 Common types of rules and tapes.

Generally, a rule has four sets of graduations—one on each edge of each side. The longest lines represent the inch marks. On one edge, each space represents 1/8 inch. The other edge of this side is divided by 1/16 marks. The 1/4 and 1/2-inch marks are commonly made longer than the smaller division marks to facilitate counting. The graduations are not, as a rule, numbered individually, however, since they are sufficiently far apart to be counted without difficulty The opposite side is similarly divided into 32 and 64 spaces per inch. It is common practice to number every fourth division of these graduations for easier reading.

There are many variations of the common rule. Sometimes the graduations are on one side only. Sometimes the graduations are added across one end for measuring in narrow spaces. And sometimes only the first inch is divided into 64ths, with the remaining inches divided into 32nds or 16ths.

To measure lengths that are greater than 18 inches, folding steel, wood, or aluminum rules can be used. They are usually 2 to 6 feet long. The folding rules cannot be relied on for extremely accurate measurements because a certain amount of play develops at the joints after they have been used for awhile.

Steel tapes are made from 6 to about 100 feet in length. The shorter lengths are frequently made with a curved cross section so that they are flexible enough to roll up, but remain rigid when extended. Long, flat tapes require support over their full length when they are used to mea sure, or the natural sag will cause an error in the reading.

The flexible-rigid tapes are usually contained in metal cases. They may wind themselves back into the case when a button is pressed or they may be easily wound with a crank. A hook is provided at one end so that the tape may be hooked over the object being measured. This allows one person to handle the tape without assistance. On some models, the out side of the case can be used as one end of the tape when inside dimensions are being measured.

Rules and tapes should be handled carefully and kept lightly oiled to prevent rust. Never allow the edges of measuring devices to become nicked from being struck by hard objects. They should preferably be kept in a wooden box when not in use.

To avoid kinking the tapes, pull them straight out from their cases. Do not bend them backward, With the windup type, always turn the crank clockwise. Turning it backward will kink or break the tape. With the spring-wind type, guide the tape by hand. If it is allowed to snap back, it may be kinked, twisted, or otherwise damaged.


Notice in FIG. 2-4 that the circle that the hook at the end of the perpendicular rule is attached so that it is free to move slightly When an outside dimension is taken by hooking the end of the rule over the edge, the hook will locate the end of the rule even with the surface from which the measurement is being taken.

To measure an inside dimension with a tape rule, extend the rule between the surfaces as shown, then take a reading at the point on the scale where the rule enters the case and add 2 inches. The 2 inches are the width of the case. The total is the inside dimension.

To measure an outside dimension with a tape rule, hook the rule over the edge of the stock. Pull the tape out until it projects far enough from the case to permit you to measure the required distance, The hook is designed so that it will locate the end of the rule at the surface from which the measurement is being taken (FIG. 2-5). When you are taking a measurement of length, hold the tape parallel to the lengthwise edge.

Fig 2-4 Measuring ns dimensions with a tape rule.

Fig 2-5 Measuring outs dimensions with a tape rule.

For measuring widths, the tape should be at right angles to the lengthwise edge. Read the dimension of the rule exactly at the edge of the piece that is to be measured. In this case, it may be necessary to butt the end of the tape against another surface or to hold the rule at a starting point from which a measurement is to be taken.


Of all the layout tools in the woodworker’s kit, the framing square is the most generally useful.

When you lay out 90- and 45-degree angles with a framing square, the lumber you work with should be squared on the ends. This will make it necessary to lay out a line at a 90-degree angle with respect to the edge of the board. This line should be as close to the end of the board as possible to avoid undue material waste. When doing this job with a framing square, place the blade of the square along one edge of the board and mark along the outside edge of the tongue, as shown in FIG. 2-6.

Fig 2-6 Using a framing square.


Another versatile tool for measuring, marking, and preparing hardwood floor strips or blocks for cutting is the combination square. To square a line on stock with a combination square, place the squaring head on the edge of the stock, as shown in FIG. 2-7, and draw the line along either edge of the blade. The line will be square with the edge of the stock against which the squaring head is held. The angle between the line and the edge will be 90 degrees.

To lay out a 45-degree angle on stock with a combination square, place the squaring head on the edge of the stock, as shown in FIG. 2-8, and draw the line along either edge of the blade. The line will be at a 45-degree angle to the edge of the stock against which the squaring head is held.

To test the trueness of 90-degree angles with a combination square, hold the body of the square in contact with one surface of the 90-degree angle and bring the blade into contact with the other (FIG. 2-9). When making this test, have the square between yourself and a good source of light. If the angle is a true 90-degree angle, no light will be visible between the blade and the surface of the work.

Fig 2-7 Squaring stock with a combination square.

Fig 2-8 Making 45-degree cuts with a combination square.

Fig 2-9 Checking a 90-degree angle with a combination square.

Fig 2-10 Using a chalk line.

The chalk line is one other useful tool that could be mentioned here (FIG. 2-10). A chalk line is a white, twisted mason’s line that consists of a reel, line, and chalk. The line is coated with chalk. When it is stretched taut between the points that are to be connected by a straight line and held just off the surface, the chalk line will make a straight guideline when it is snapped. The chalk line can be very useful when making diagonal cuts across hardwood floor boards.


Anyone who works with wood uses a large variety of hand tools. Of these, woodcutting hand tools are often the most used—and abused.

Fig 2-11 Using a common carpenter’s saw,

The most common carpenter’s handsaw (FIG. 2-11) consists of a steel blade with a handle at one end. The blade is narrower at the end opposite the handle, which is called the point or toe! The end of the blade nearest the handle is called the heel. One edge of the blade has teeth that act as two rows of cutters. When the saw is used, these teeth cut two parallel grooves close together. The chips or sawdust, are pushed out from between the grooves, or kerfs, by the beveled part of the teeth. The teeth are bent alternately to one side or the other to make the kerf wider than the thickness of the blade. This bending is called the set of the teeth.

The number of teeth per inch, the size and shape of the teeth, and the amount of set determine how the saw should be used and the type of material that it should cut. Carpenter’s handsaws are described by the number of points per inch. There is always one more point than there are teeth per inch. A number stamped near the handle gives the number of points of the saw.

Fig 2-13 Cutoff saw teeth.

Fig 2-14 Combination saw teeth.

Woodworking handsaws consist of ripsaws and crosscut saws that are designed for general cutting. Ripsaws are used for cutting with the grain, and crosscut saws are used to cut across the grain. The major difference between a ripsaw and a crosscut saw is the shape of the teeth. A rip- saw tooth has a square-faced, chisel cutting edge (FIG. 2-12). It does a good job of cutting with the grain, which is called ripping, but a poor job of cutting across the grain, which is called crosscutting. A crosscut saw tooth has a beveled, knife-like cutting edge, like the one in FIG. 2-13. It does a good job of cutting across the grain, but a poor job of cutting with the grain. Figure 2-14 illustrates a combination saw blade that offers the qualities of both the ripsaw and the crosscut saw, Special handsaws

The more common types of saws, which are used for special purposes, are shown in FIG. 2-15. They can be useful as you notch hardwood floor strips or blocks around pipes or make critical cuts.

The backsaw is a crosscut saw that is designed for sawing a perfectly straight line across the face of a piece of stock. A heavy steel backing along the top of the blade keeps the blade perfectly straight. The dovetail saw is a special type of backsaw that has a thin, narrow blade and a chisel- like handle.

The compass saw is a long, narrow, tapering ripsaw that was designed to cut out circular or other nonrectangular sections from within the margin of a board or panel. A hole is bored near the cutting line to start the saw. The keyhole saw is simply a finer, narrower compass saw. The coping saw is used to cut along the curved lines, as shown in FIG. 2-15.

Caring for handsaws

Some of the right and wrong methods of using and caring for a handsaw are shown in FIG. 2-16. A saw that is not being used should be hung up or stored in a toolbox. A toolbox that is designed for holding saws has notches that hold them on edge with the teeth facing up. If you store saws loose in a toolbox, the saw teeth may become dulled or bent from contact with the other tools.

Fig. 2-15. Special saws for special jobs: Back saw; Dovetail saw; Compass saw; Coping saw

Fig. 2-16: Caring for handsaws:

1. When work is complete, hang up the saw,

2. Do not pile tools on top of the bench so as to distort blade.

3. Look carefully over repair or alteration work; see that all nails are removed to avoid cutting into metal.

4. Strips of waste should not be twisted off with blade, but broken off with hand or mallet.

5. Supporting the waste side of work will prevent splitting off.

6. Raise the work to a height sufficient to keep the blade from striking the floor. If the work cannot be raised, limit the stroke.

Before you use a saw, be sure that there are no nails or other edge- destroying objects in the line of the cut. When sawing out a strip of waste, don’t break out the strip by twisting the saw blade. Doing this dulls the saw and may spring or break the blade.

Be sure that the saw will go through the full stroke without striking the floor or some other object. If the work cannot be raised high enough to obtain full clearance for the saw, you must carefully limit the length of each stroke.

Sawing aids

A miter box (Fig. 2-17) permits you to saw a piece of stock at a given angle without laying out a line. The figure shows a common type of wooden 45-degree miter box. Stock can be cut at 45 degrees by placing the saw in cuts M-S and L-F, or at 90 degrees by placing the saw in cuts A-B.

The sawhorse (Fig. 2-18) might be called the carpenter’s portable workbench and scaffold. If you don’t already have a good sawhorse, follow the directions in the illustration and make one. Not only is the saw- horse practical, but making one is a good exercise in how to use your handsaw and measuring tools. It also will help you gain an understanding of wood.

Fig 2-8 Dimensions for making your own sawhorse.

Fig 2-19 Portable electric circular saw.


The portable, electric circular saw (FIG. 2-19) is one of the most popular tools for the do-it-yourselfer. It can be used for any purpose that would take a handsaw, while offering the advantage of speed. The size of a portable circular saw is designated by the maximum diameter of the blade in inches that it will support within its guard.

To make an accurate rip cut, the ripping guide (FIG. 2-20) is set a distance away from the saw that is equal to the width of the strip that is to be ripped off and placed against the edge of the piece as a guide for the saw. When the cut is finished, the ripping guide is turned upside down so that it will be out of the way

Circular saws use circular blades. The types of blades are the same as those available on handsaws: ripping, crosscutting, compass, and combination.

Power saw safety

All portable, power-driven saws should be equipped with guards that automatically adjust themselves so that none of the teeth protrude above the work. The guard over the blade should be adjusted so that it slides out of its recess and covers the blade to the depth of the teeth when the saw is lifted from the work. Goggles or face shields should be worn while using the saw and while cleaning up the debris afterwards.

Fig. 2-20 Ripping with a portable circular saw, using a ripping guide (A).

Saws should be grasped with both hands and held firmly against the work. Care should be taken that the saw does not break away, which could cause an injury. The blade should be inspected at frequent intervals and always after it has locked, pinched, or burned. Pull the plug to break the electrical connection before this examination. Do not overload the saw motor by pushing too hard or cutting stock that is too heavy for the saw.

Before using the saw, carefully examine the material that is to be cut. It should be free of nails or other metal substances. Cutting into or through knots should be avoided as much as possible.

The electric plug should be pulled before any adjustments or repairs are made to the saw, including blade changes.


The carpenter’s level (FIG. 2-21) determines the levelness of a surface and allows you to sight level lines. It may be used directly on the surface or with a straightedge (FIG. 2-22). The levelness of an object is determined by the bubbles that are suspended within glass tubes that are parallel to one or more surfaces of the level (FIG. 2-23).

Fig 2-21 Carpenter’s level.

Fig 2-22. Straightedge used with a carpenter’s level.

To level a surface, such as the workbench in FIG. 2-24, set the carpenter’s level on the bench-top parallel to the front edge of the bench, Notice that the level may have as many as three or more pairs of glass vials. Regardless of the position of the level, always watch the bubble in the bottom vial of the horizontal pair. Shim or wedge up the end of the bench that will return the bubble to the center of its vial. Recheck the first position of the level before you secure the shims or wedges. These principles can easily be applied to the leveling of flooring material with a carpenter’s level and shims.

The line level (FIG. 2-25) has a spirit bubble that shows levelness as it is hung from a line. Placement halfway between the points that are to be leveled gives the greatest accuracy.

Fig 2-23 Smaller carpenter’s level with horizontal and vertical bubble tubes.

Fig 2-24 Using the carpenter’s level to check for a level working surface.

Fig 2-25 Line level.


The carpenter’s curved-claw nail hammer (FIG. 2-26) is a steel-headed, wooden-handled tool that is used to drive nails, wedges, and dowels. The claw, which is at one end of the head, is a two-pronged arch that is used to pull nails out of the piece of wood. The other parts of the head are the eye and face.

Fig 2-26 Carpenter’s curved-claw nail hammer components: The hammer; Wedge; Neck; Handle; Cheek; Head; Adz eye; Face

Fig 2-27 Bell- and plane-faced claw hammers. Bell faced claw hammer; Plain faced claw hammer

The face may be flat, in which case it is called a plain face (FIG. 2-27). The beginning woodworker will find the plain-faced hammer the easiest hammer to use to learn to drive nails. With this hammer, however, it is difficult to drive the nailhead flush with the surface of the work without leaving hammer marks on the surface.

The face of a hammer may also be slightly rounded or convex, in which case it is called bell-faced. The bell-faced hammer is generally used in rough work. When handled by an expert, it can drive the nail flush with the surface of the work without damaging the surface.

To use a hammer, grasp the handle so that the end is flush with the lower edge of your palm (FIG. 2-28 . Keep your wrist limber and relaxed.

Fig 2-28 Correct way to use a hammer. Handle flush with edge of palm; Face strikes squarely.

Fig 2-29 Wrong way to use a hammer: Handle “choked” (hand too far up on handle); Face strikes at angle. Results in bent nail.

Grasp the nail with the thumb and forefinger of your other hand and place the point at the exact spot where it is to be driven. Unless the nail is to be purposely driven at an angle, it should be perpendicular to the surface of the work. Strike the nailhead squarely and keep your hand level with the head of the nail. To drive, first rest the face of the hammer on the head of the nail. Then raise the hammer slightly and give the nail a few light taps to start it and fix the aim. Then take your fingers away from the nail and drive the nail with firm blows with the center of the hammer face. The wrong way to drive a nail is shown in FIG. 2-29.


Nailing two pieces of wood together is one of the most common tasks in carpentry and one that you’ll be able to practice many times as you install your hardwood floors. If the joint doesn’t hold or the wood splits, it is generally because the installer didn’t observe a few basic rules for nailing.

First of all, if the joint is to hold properly, the nail must be long enough. A good rule to follow here is to select a nail three times the length of the thickness of the wood that is to be nailed. If the nail is too short, it cannot hold properly If it is too long, the increased diameter may split the wood. There will be more information on how to select nails later in this section.

Fig 2-30 Toenailing.

A few properly spaced nails will hold better than many nails that are put in at one point. Improper spacing or too many nails will split the wood and not add strength to the joint. A nail that is driven in at an angle, which is called toenailing (FIG. 2.30), will provide a stronger joint than a nail that is driven straight down.

When the end of the nail extends through the second piece of wood, it should be clinched or bent over, Although clinching the nail with the grain will give a smoother surface, clinching across the grain will give more strength.

The head of a finishing nail should be set below the surface of the wood (FIG. 2-31) with a nail set and the resulting hole filled with putty or plastic wood. Whenever a finished appearance is desired, drive the nail almost to the surface with the hammer and finish the job with a nail set (FIG. 2-32). This method will keep you from striking the wood with the face of the hammer and denting it.

When you use a claw hammer to pull out nails, insert a block of wood under the hammer to provide more leverage and to prevent the hammer from damaging the wood. If the nail has been clinched, it should be straightened before any attempt is made to remove it.

Fig 2-31 Filling over a set finish rail.

Fig 2-32 Commonly used punches: Center punch; Starting punch; Pin punch; Aligning punch; Hollow shank gasket punch

Considering how inexpensive nails are, it is a waste of time and materials to try to straighten nails for reuse. Once a nail has been used and bent back and forth, it has lost much of its holding powet Moreover, it is almost impossible to straighten a nail perfectly The result is a bent nail that must be removed, possibly resulting in damage to the wood.


Figure 2-33 shows the more common types of wire nails. The brad and the finish nail both have a deep countersink head that is designed to be set below the surface of the wood. The casing nail has a flat countersink head, which may be driven flush and left that way or which may also be set. The other nails shown are all flat head nails.

2-33 Common types of wire nails: (A) brad, (B) finish nail, (C) casing nail, (D) box nail, (E) common nail, (F) spike (larger than 60d) (G) duplex head nail,

The common nail is the one most widely used in general wood construction. Nails with large flat heads are used for nailing roofing paper, plaster board, and similar thin or soft materials. Duplex or double-headed nails are used for nailing temporary structures, such as scaffolds, that will eventually be dismantled. A duplex nail has an upper and lower head. The nail is driven to the lower head so it can be easily withdrawn by setting the claw of a hammer under the upper head.

Besides nails with the usual type of shank, which is round, there are various special-purpose nails with shanks of other shapes. Nails with square, triangular, longitudinally grooved, and spirally grooved shanks have a much greater holding power than wire nails of the same size. One you may come across is the flooring nail (FIG. 2-34), which is driven diagonally through the tongue of the board and into the subfloor. The availability of these nails, however, is somewhat limited for the do-it-yourselfer and the skill required for placement is high, so they are usually not used.

The lengths of the most commonly used nails are designated by the penny system. This system originated in England where the abbreviation for the word penny is the letter d. Thus, the expression two-penny nail is written 2d nail. The thickness of a nail increases with the penny size and the number of nails per pound decreases. A box of casing nails of the same common nail penny size is thinner. Consequently, it takes more boxes to get the same weight.

Fig 2-34 Flooring nail that is blind-nailed into tongue-and-groove hardwood flooring strip.

The penny sizes and corresponding lengths, thicknesses (in gauge sizes), and numbers per pound of the most commonly used nails are shown in TABLE 2-4. Relative sizing is shown in FIG. 2-35. Recommended nailing methods and sizes for specific home construction projects are given in TABLE 2-5.

The lengths of nails that are larger than 60d, which are called spikes, are designated in inches. Nails smaller than 2d are designated in fractions of an inch.


Wood screws (FIG. 2-36) are designated by the type of head and the material, such as flathead brass or roundhead steel. Most wood screws are made of either steel or brass, but there are copper and bronze wood screws as well. To distinguish the ordinary type of head from the Phillips head, the former is called a slotted head. A lag screw is a heavy iron screw that has a square bolt-type head. Lag screws are used mainly for fastening heavy timbers, but they can also be used for the installation of hardwood plank floors.

The size of an ordinary wood screw is designated by the length and the body diameter, or unthreaded part, of the screw (FIG. 2-37). Body diameters are designated by gauge numbers that run from 0, for about a 1 diameter, to 24, for about a 3/8 diameter. Lengths range from 1/4 inch to 5 inches. The length and gauge numbers are printed on the box, as 1 ¼ - 9. This means a 9 gauge screw 1 1/4 inches long.

Note that for a nail a large gauge number means a small nail, but for a screw, a large gauge number means a large screw. TABLES 2-6 and 2-7 will guide you through the sizes of wood screws.

Figure 2-38 illustrates how screws can be countersunk through hard wood flooring and the subflooring. First, drill the body hole completely through the flooring. Then drill the starter hole, which is a little less than the diameter of the wood screw. Finally, if a flathead wood screw or oval head wood screw is to be used, countersink the body hole as shown.

Thus far in this section, you’ve learned a great deal about planning hardwood floors and the tools you’ll need to install a hardwood floor.

Now you will see how a home is constructed from the ground up, with emphasis on how it is prepared for the installation of hardwood flooring.

Table 2-4 Sizes of Commonly Used Nails

  • Common Wire Nails
  • Flooring Brads
  • Finishing Nails
  • Smooth & Barbed Box Nails
  • Casing Nails

Table 2-5 Recommended Nailing for Houses

3-inch edge and 6-inch intermediate.


There are several types of mastic available that are satisfactory for use when laying hardwood floors. Hot asphalt is generally used only for laying screeds on concrete, and then the screeds must be positioned immediately after the mastic is poured. Cutback asphalt, chlorinated solvent, and petroleum-based solvent mastics are all applied cold and are always used for laying block and parquet floors. Cutback asphalt is also used to hold a membrane damp-proofing. Follow the manufacturers’ instructions on coverage, drying time, and ventilation.

Trowels usually have both straight and notched edges. The notched edge is for use where a correct mastic thickness is specified. Both mastic and trowels are available from flooring manufacturers and distributors.

Fig 2-35 Relative nail sizes.

Fig 2-36 Common types of wood screws.

Fig 2-37 Wood screw heads and components.

Table 2-6 Screw Threads per Inch: Diameter; Threads Per Inch

Fig 2-38 Countersinking holes for screws when attaching hardwood flooring.

Table 2-7 Screw Sizes and Dimensions


One of the first essentials in house construction is to select the most desirable property site for its location. A lot in a smaller city or community presents few problems. The front setback of the house and side yard distances are either controlled by local regulations or governed by the other houses in the neighborhood.


The footing is located at the base of the foundation (FIG. 2-39) It is made of concrete and is wider than the actual foundation so that the weight of the house will be distributed over a greater area, If the footing is not the right size for the weight of the house and the soil conditions, it will sink and the house will settle.

Fig 2-39 Foundation and footing.

The foundation is the masonry which sits on top of the footing and supports the weight of the house. It also provides the walls for the basement. The foundation can be made of stone, cement, cinder blocks, poured concrete, or any other material that can sustain a considerable load.

Fig 2-40 Foundation prior to sill installation (no image).

Fig 2-41 Close up of sill bolts embedded in foundation.

Fig 2-42 Sill plate installed with sill bolts.

The sills (FIGS. 2-40 through 2-42) are the wood or steel beams that are attached to the top of the foundation. The house is built up from the beams.

Girders (FIGS. 2-43 through 2-45) are the large beams that run between opposite sills. They are used to provide additional support for the frame of the house, as well as to carry the flooring.

Fig 2-43 Flooring girders are installed on foundation piers.

Fig 2-44 Girders fit into notches in the perimeter foundation.

Fig 2-45 Typical girder and intertied joists.

The floor joists (FIGS. 2-46 and 2-47) are the beams that run across the sills and provide a base for the flooring. Floor joists are generally made of 2 x 10 or 2 x8-inch lumber, depending on the distance they must span. The joists are placed broad-side upright to provide greater strength. In well-constructed homes, they are spaced 16 inches from center to center.

Fig 2-46 Floor joists attached to the box sill.

Fig 2-47 Floor framing p showing joists and other components.

The bridging (FIG. 2-48) consists of small strips of 1 x 3-inch lumber, or a size near this, that are nailed diagonally between the floor joists along the center of the span. The purpose of the bridging is to keep the joists perpendicular so that they will provide the maximum amount of support and to distribute the weight on the floor between several joists rather than one or two. Bridging can also be made out of strips of metal.

Fig 2-48 Bridging installed in typical floor framing.

Fig 2-49 Installation of the typical subfloor.

Fig 2-50 Actual installation of subfloor (no image)

Fig 2-51 Close-up of subfloor installation (no image)

The subfloor (FIG. 2-49) is the under flooring to which the finish floor is nailed. The subfloor is nailed directly to the floor joists and runs either at a 45- or 90-degree angle to the joists. The subfloor or rough floor not only furnishes a base for the finish floor, but also adds a degree of strength to the frame of the house. Figures 2-50 and 2 show an actual installation of subflooring.

An important part of energy efficiency in the home is the installation of adequate insulation under the flooring. Figure 2-52 illustrates how batt insulation is placed under flooring. This batt insulation is usually 48 inches long and 15 or 23 inches wide, depending on whether the joists are placed 16 or 24 inches apart.

Fig 2-52 Install batt insulation under subfloor.

Fig 2-53 Double-studding intersecting walls.

hand view of FIG. 2-54. The stringers shown here are cut out of solid pieces of dimensional lumber (usually 2 x 12) and are therefore called cut outs or stringers.


Figure 2-55 illustrates how the finish flooring is added on to the house construction. Figure 2-56 illustrates how square-edged flooring is nailed and installed over the subflooring. First, building paper is installed on top of the subflooring. Then the finish flooring is installed at right angles and face-nailed.

Fig 2-55 Installation of finish flooring over joists, bridging, girder, and subflooring.

Fig 2-56 Nailing square-edged flooring.

Figure 2-57 shows the steps for installing tongue-and-groove finish flooring over a subfloor. Again, building paper can be applied between the subfloor and the finish floor in order to keep moisture from coming up through the subfloor and damaging the flooring.

In the next section, you’ll learn the specific steps for the installation of hardwood strip and block flooring in a variety of situations and using the numerous types of flooring that are available to the consumer. Remember that the planning of your hardwood flooring job is vital to its success.

Fig 2-57 Nailing tongue-and-groove finish flooring.

Next: Installing Hardwood Floors

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Monday, 2009-01-12 23:14