I go to work later than usual by 30 minutes on Saturdays and Sundays.
I get to work later than usual by 30 minutes on Saturday and Sundays.
"土日は平日より30分遅くオフィスへ行く"
土日は on Saturdays and Sundays
遅く late
30分 30 minutes
いつもより遅く later than usual
オフィスに行く go to work, get to work, arrive at work
I go to work later than usual by 30 minutes on Saturdays and Sundays.
I get to work later than usual by 30 minutes on Saturday and Sundays.
I go to the office 30 minutes later on weekends than on weekdays.
「I go to the office 30 minutes later on weekends than on weekdays」は「土日は平日より30分遅くオフィスへ行く」という意味です。"on weekends"は「土日」、"on weekdays"は「平日」を指します。"30 minutes later"で「30分遅く」となり、比較のために"than"を用いています。
他の表現例として、
・On weekends, I start work 30 minutes later than usual.
『週末はいつもより30分遅く仕事を始めます。』