Ymaa123 Ama

My question is, my office is based 25 miles away from my home.(not self employed)I work majority of the time from home and I go in once a week to the office. During the week I visit various sites where I carry out temporary work. I wanted to know if, so most of the temporary work is not beyond or past my permanent workplace. I wanted to know if I can claim mileage for example on from home to a temporary work place that is 18 miles. The ordinary commute is confusing me.