As a construction worker i drive to multiple sites a month. Can i write off all the miles for that seeing as i don't have a set work location?

[DawnC0]

These miles are considered commuting miles unless they are for work location outside of the metropolitan area where you live and normally work.  You may deduct the cost of going between your residence and a temporary work location outside of the metropolitan area where you live and normally work.  You cannot deduct daily transportation costs between your home and temporary work sites within your metropolitan area. These are nondeductible commuting expenses.  

If you work at two job-sites in one day, whether or not for the same employer, you can deduct the expense of getting from one workplace to the other. However, if for some personal reason you do not go directly from one location to the other, you cannot deduct more than the amount it would have cost you to go directly from the first location to the second.