Do I get paid time and a half on Sundays if I work installing floors?

You'd have to ask your boss. Overtime is not mandatory.

You should but some companies dont

Federal labor laws state, and in most states, that any hours worked over 40 in any given week, you are to be paid time and a half for you hours worked over 40. However in California it is, I'm told, over 8 hours in a day and over 40 hours in a week. So in California you work 10 hours in a day you get 1 1/2 times you wage for every hours over 8 and if you work over 40 hours in a week you get 1 1/2 times your wage for all hours over 40 hours. Elsewhere you only get straight time unless you work more then 40 hours in a week, doesn't matter what day of the week it is.