I just had my residential roof done yesterday. I asked the roofer to install ridge vents. He used the GAF Cobra ridge vent. I went on the roof today and can barely see anything. This doesn't seem right. Shouldn't the venting be more visible than this? I think very little air can flow. Also, the slots underneath seem not wide enough. Could the slots be wider than what I am seeing (that is, the full slot width could be blocked by the wood I am seeing)?