||roofing hatchet (hammer)*
Which is better? Hand nailing or air nailing? That is the question. Here is the answer: Hand nailing is far superior. Air nailing not even remotely close in quality to hand nailing. Too bad almost nobody does hand nailing anymore. I hand nailed everything, including plywood. I didn't even bring an air compressor to the job unless it was for blowing dust off the roof or my clothes.
98% of 'roofers' use air guns, which is the main reason at least 85% of all roofs are installed incorrectly. By using air power, it is very possible that the blowoff portion of your manufacturer's warranty will be void.
Air nailing is beneficial to both the contractor and the installer, but NOT the property owner! Good for the contractor because the job goes faster. Good for the installer beacause nearly all companies pay PIECEWORK, which encourages speed; so the more the installer does in a day the more they earn. Natural inclination.
If you hear an air nailer going so fast that you cannot differentiate between the individual trigger pulls, then your roof is likely being installed IMPROPERLY. All manufacturers are VERY SPECIFIC about nailing. EVERY bundle of shingles made by EVERY manufacturer includes a diagram regarding nailing. The nails MUST be perpendicular to the deck. The nail heads MUST be flush with the shingle surface and not raised above or pushed through. The nails MUST be precisely placed. You cannot put them just anywhere.
I was a special witness for a homeowner who caught the roofer not abiding by the contract. He refused to pay for the roof. Lawyers became involved. The huge production-oriented local company was pulling out all the stops. I was asked by counsel to take 100 photos of the improper nailing. I pried up 100 shingles and found nails pushed through, applied at an angle and incorrectly placed, as well as not the correct number of nails per shingle.
I marked each black shingle with my yellow crayon. Each was numbered 1 through 100. I made documents explaining what was going on in each photo. One day before the case was to go to trial, the 'roofer' threw in the towel. We prevailed. The homeowner got a free roof and all attorneys costs paid. True story. The homeowner's testimonial is on the Testimonials
Another negative about nailing guns is that you cannot 'feel' whether the nail is going into wood or air. With hand nailing you can. Many roofs are installed over 1X8 shiplap boards, which were used in the old days before the introduction of plywood. These boards have wide gaps and many knot holes; therefore, a percentage of the nails will not go into solid wood. The likelihood of blowoff increases.
Any roof with 1X8 shiplap should be covered with plywood. By doing this, you know every nail is hitting solid wood; but most roofers will not do this because the other way IS CHEAPER. Another benefit of 1/2" plywood over 3/4" thick shiplap is that you end up with a total of 1 1/4" of wood for the fasteners to bite into. Walking on a roof deck with these two layers of wood feels like you are walking on the ground. Installing plywood raises the price of the job, reducing the contractor's chance of getting the job when the competition omits plywood. However, installing plywood is the right way
to do it!
Virtually nobody will lay it out for you as I just have. Either they don't know this or they don't care. I see it ALLTHE TIME. Production and profit trump quality. And really, a good hand nailer can nearly keep up with a gun user. But most important, with hand nailing you know that 99% of all nails are correctly applied.
If you ask most roofers about hand nailing, just wait for the funny look they give you. Nearly all installers have never done it with a hatchet (roofing hammer). The idea terrifies them. Pay a little extra. GET IT HAND NAILED.
* About Roofing Hammers
Roofing hammers (aka hatchets) are funny looking. They have a round pin at the end, which is the 'gauge'. The gauge makes the rows straight. Althought bottom liners and General Managers look at you like you're nuts if you bring up hand nailing, any architect or (real) builder will tell you hand nailing FAR superior for all the reasons I laid out.