Avoid describing a weakness that would keep you from successfully performing your job. For example, if you say that you do not work well with others, the interviewer will see that as a deal-breaker since you need to be a team player in the roofing industry. Choose a weakness that will not interfere with being a great employee.

"My greatest weakness is my lack of experience installing tile and slate roofing. My experience as a Roofer has been installing roofing on commercial buildings, but I would like to be more well-rounded. That is why I am excited to be interviewing with your company since you offer on-the-job training in installing other types of roofing material. I want to turn my weakness into a strength, and I see that is possible with your company."