The advantage of using wood screws over nails and staples is that they are superior in applications where firm joints are required because of the high clamping force created between the wood or metal attachment and the surface of the wood into which the screw is driven.
Wood screws can be removed and replaced if any subsequent adjustment to the assembly is necessary. Adjustment is not possible to nailed joints particularly if the nails and staples have been clinched. Unclinched nails can be removed but not without causing damage to the exterior face of the attachment.
When deciding on which length screw you need for the application it is important to remember that a screw should penetrate the substrate (joist) 60 percent of its length.
Not sure what size pilot hole you need to drill for hard woods? Here is our recommendation of pilot hole sizes you need for various screw guages:
| Imperial Gauge | Metric Equivalent (MM) | Nominal (MM) | Drill Size (MM) |
| 3 | 2.4 | 2.5 | 1.45 |
| 4 | 2.7 | 3 | 1.70 |
| 5 | 3.1 | 3 | 1.85 |
| 6 | 3.5 | 3.5 | 2.10 |
| 7 | 3.8 | 4 | 2.30 |
| 8 | 4.2 | 4 | 2.50 |
| 9 | 4.5 | 4.5 | 2.65 |
| 10 | 4.9 | 5 | 2.75 |
| 12 | 5.6 | 5 | 3.15 |
Due to the wide variants in brick, block and concrete densities the pilot hole diameter required can vary dramatically. In most instances, one would drill one millimetre in diameter less than the screw diameter.
Not sure on the spacing of woodscrews you need for your application? See the table below for guidance.
NB: spacing is subject to a screws load bearing capacity.
| Driven Without Pre-Drilled Holes | Driven into Pre-Drilled Holes | |
| Distance from End | 20 D | 10 D |
| Distance from Edge | 5 D | 5 D |
| Distance between Lines of Screws | 10 D | 3 D |
| Distance along the grain between adjacent screws | 20 D | 10 D |
Many corrosion problems occur when two dissimilar metals are in contact, leading to electro-chemical activity in damp conditions. This can be reduced or eliminated by controlling the ambience (e.g. limiting the humidity), or isolating dissimilar metals by insulating compounds, washers etc. Further protection can be given by applying coatings of grease, paint, waxes, etc.
PLEASE NOTE: THE ABOVE INFORMATION IS FOR REFERENCE ONLY. THIS CAN DIFFER DEPENDENT UPON THE APPLICATION.