Nailing is the most basic and most commonly used means of attaching members in wood frame construction. Usually, nailing is used as a structural connection and appearance is not a factor. Exceptions to this are nails used for cladding, decking and finish work, where care in the selection of the type of nail can lead to enhanced appearance.
Screws rely on their threads to develop resistance to withdrawal. Nails are faster to install but rely mainly on friction to resist withdrawal. For this reason, designs should ensure that nails are loaded laterally and that withdrawal loads are kept to a minimum as shown in Figure 5.1 in the previous section.
Nails are made in lengths from 13mm (1/2") to 150mm (6"). Spikes are made in lengths from 100mm (4") to 350mm (14") and are of sturdier proportion than nails.
Types of Nails
In Canada, nails are specified by the type and length and are still manufactured to Imperial dimensions. Diameter is specified by gauge number (British Imperial Standard) and is the same as the wire diameter used in manufacture.
In the U.S., the length of nails is designated by "penny" abbreviated "d". For example a twenty-penny nail (20d) has a lenth of four inches.
Pneumatic or mechanical nailing guns have found wide-spread acceptance in North America due to the speed with which nails can be driven. They are especially cost effective in repetitive applications such as in shearwall construction where nail spacing may be as close as 75mm (3") to distribute load.
The nails for power nailers are lightly attached to each other or joined with plastic, allowing quick loading nail clips, similar to joined paper staples. Fasteners for these tools are available for every application from heavy framing nails up to 89mm (3-1/2") down to upholstry staples 4.8mm (3/16") in length. These fasteners are also available in galvanized form for corrosive applications.
Figure 5.2: Nail Types