Do graduate schools dislike when students take 5 years in undergrad?
You want to make a double major program, I don't know the issues in your university but here they still finish their own undergraduate degree in time and took their diploma, and in their extra year solely took courses of double major. So actually no extra year in the curriculum as a result. 
Still, graduate schools demand explanations for an extra year. I have finished Chemistry (4 years) in 6 years in my university. First 2 years are simply filled with N/A or FF grades of retaken courses. I was unable to attend my classes and even most of the exams due to the economic reasons. Most of the time I had worked in places with more than 40 hours in a week, and sometimes 17 hours a day for most of the week. 

In short, if you prove to graduate schools you applied, that you have an extra year not because of incompetence or other serious lackings, but due to living conditions or meaningful academic reasons; they will tolerate that. However, be wary of some schools which count your retaken/replaced courses as another course in your curriculum, so in their way of calculating your GPA might be worse.