3-inch self-tapping roofing screws are most commonly used to fasten metal roofing, with the exception of the 1-inch roofing screws which can sometimes be sufficient to fasten the first edges of metal roof sections. However, when installing a metal roof over an existing asphalt roof, the first few edges of each of its sections must be fastened with 3-inch roofing screws.
Self-tapping roofing screws are essential to simplifying the installation of metal roofing that is not factory pre-drilled or countersunk, as they are both quicker to attach and reduce the risk of injury from broken screws. Visit more here about this topic.
Sealing of metal roofs
Because metal roofing does not contain anything that seals the holes around the roofing screws in the way that asphalt roofing materials seal the holes around the roofing nails, roofing screw manufacturers make two types of roofing screws. The first has a metal locking cap that sits directly on top of the roofing material and is secured by the screw itself. The second has integrated plastic or rubber washers in their bodies, which automatically seal the holes in the roofing when inserted.
Alternatives for roofing screwdrivers
Metal roofing should not be installed by hand as this requires the roofing screws to be no more than two feet apart. Driving that number of roofing screws by hand would quickly exhaust the hand and arm strength of the roofing crew, and relying on the rechargeable roofing screwdrivers now available would mean switching for fresh batteries every hour. Since most rechargeable roofing tool batteries take an hour to charge, each member of the roofing crew would need four batteries to complete an eight-hour shift!
One solution would be to use an electric roofing screwdriver that can work all day without a break. Most of these screwdrivers are made with adjustable power levels that allow their users to select just the right amount of force to use when installing the roofing screws.
Roofing screws that are driven too deep into a roof can either damage the roof itself or break off their piles, making removal very difficult. The downside to using an electric-powered roof wrench is that it rewires the use of a long extension cord, which can pose a hazard to those working on the roof.
The third alternative for installing roofing screws is the pneumatic screwdriver, which is powered by an air compressor. The pneumatic patio roof wrench is attached to its air compressor with a long air hose which, like an electric screwdriver extension cord, can become a real drag when dragging around on the roof.
