Architectural shingles are a great choice for your home. They offer good protection from the elements and last longer than the old 3-tab shingles. Unfortunately they are not always installed correctly. The shingles in this picture were not nailed in the right place. This is worse on steep slopes. What happens when the shingles are nailed too high is that the top part of the shingle delaminates from the bottom part of the shingle when they get hot. If nailed correctly, the nail will hold both parts together. Sometimes when an installer gets in a hurry, they nail the shingles too high missing the nail strip. The shingle heats up in the sun and gravity pulls the shingle apart. We repair a lot of roofs that were not installed properly. The best bet is to have supervision on the roof when the shingles are installed.