Back in 1995 I did a layover on our house right before selling it. I hand-nailed. It took me a day to do 1/2 of one side of the house. The next day I rented an air-nailer. It took me one day to finish the other half of that side, the entire 2nd half of the house, the breezeway, and the garage. Never used a hammer for roofing again. It's nuts to think about the time spent and physical damage to your joints until you do it yourself.
Two summers ago we added a 24x24 addition to our garage. I bought a framing nailer from Harbor Freight. This one. $100.
Amazing deals on this 21 Degree Framing Nailer at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
It worked so well, that I bought a palm nailer from Harbor Freight. This one. $20 on sale. Used it to put in the roof truss brackets.
Amazing deals on this Compact Palm Nailer at Harbor Freight. Quality tools & low prices.
www.harborfreight.com
It worked so well, that I bought a roofing nailer from Harbor Freight. This one. It was on sale for $100, as I recall. I also bought a case of nails.
Amazing deals on this 15Deg Coil Roofing Air Nailer at Harbor Freight. Quality tools & low prices.
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It worked flawlessly.
I did 1/2 the roof one day, and the other half the next. Goes really fast. I do not want to think of how sore I'd have been using a hammer. I've had a torn rotator cuff before. No thanks.
I purchased enough shingles to also do the roof on the original garage, which was around 50 years old. So, the next summer, I bought a shingle removal shovel from Lowes or Menards (can't remember which), and removed the original shingles. It took me about 2-3 hours to remove each half of the 24x20 roof. I was surprised at how fast old shingles can be removed by one person with that shovel. Again,
I then replaced any damaged wood, put down ice shield, then tar paper, then new shingles, new metal edges, drip rail, etc., again using the HF roofing nailer, and again being very happy with the results.
As mentioned, just be sure and drip air oil into the air inlet before use each day. Doesn't hurt to do it again after lunch.
I wouldn't hesitate to purchase these Banks nailers for small projects like this. Hope that helps. Good luck with your project.