The Facts about Hand-Nailed roof shingles vs. Air Nailed roof shingles.

I’ve been in the roofing industry in the Vancouver area since 1986.  My father before me since 1946.  During this time we’ve seen a lot of changes to the residential roofing industry, everything from products, methods, and tools.

One of the most debatable installation procedures is the use of Air Nail Guns for Roofing installation.  Air-Guns have been blamed for being a venue for the sloppy installation of Nails.  Such installation flaws as over driven nails, under driven nails, crooked nails, and nails installed in the wrong area of the product as the installer is moving to quick with decreased accuracy.

Another less noted, but equally concerning problem is the damage cause by the impact of the tool.  Many times, in cooler temperatures, and even warm temperatures, the impact will shatter the asphalt around the nail and damage the integrity of the product in those areas.  Nail may look installed properly, but the product is damaged.  It may be harder to notice but it is still a prevalent problem.

Tools and Products have even been designed to help mitigate the problems created by Air Tools.  Some products have increased area for nailing to help with accuracy problems.  Some Air Tools have gauges to help adjust the depth the nail will be driven.  Tool improvements have helped to ensure nails are driven straighter.

Installation, Inspection and Insurance Companies have even draw attention to the problems associated with Air Tools and some take steps to pro-actively address issues from the use of Air Tools.  It’s a difficult balancing act to keep the air pressure at the right level.  Changes in the integrity of the roof deck, temperature, and air pressure from use make it difficult to ensure consistency when using air tools.  Asphalt shingles are a thin, soft and unforgiving product in comparison to wood products such as Fir or Spruce.  Slight changes in a few factors may make a big difference to how the nail is set.

In my opinion, I believe that a good installer will be able to install a quality roof with air-tools given they are prepared to:

• Slow down, and be observant of each nail installed.
• Ensure nails are installed correctly and in the nail zone of the product being installed.
• Pull crooked nails and repair the product with an approved caulking.
• Remove nails installed just above the head-lap of the shingle below, or the bonded area of the shingle that may have damaged the product, and repair the product.
• Pull over driven nails, and repair or replace the product.
• Pull all nails that have shattered the matting of the product from impact and repair.
• Use a hammer/hatchet to finish the installation of nails that are under driven.

Reece Jorgensen.