Today on a roof, metric three tab shingles, the home owner had the right color but only had standard sizeĀ  shingles to replace blown off ones. The roof had been repaired with those before but had been overlapped so as to not have odd sizes. I had to take some off and replace new ones the right way. The original job was a redo over other three tab shingles. The main problem with the redo that allowed the wind to blow shingles off, was the fact that using a nail gun only works when the nails go in straight, not at an angle, and when they are placed in the recommended place.

LESSON: when using a nail gun, remember the nails must go straight in not at an angle and they must be in the right places.

LESSON: use the ring size shingle when repairing.