You can make time for side projects on weekends as well as weekdays. On weekdays taking an hour out of your schedule either in the morning or night after getting back home from work and 2-3 hours on weekends are more than sufficient to work on side projects. I have 9 hour shift daily for 5 days a week and still I get enough time to write technical articles on my blog and work on mobile/web applications in spare time following similar approach. It all comes down to setting your priorities and efficient use of time. Instead of wasting time browsing social media sites or watching series on tv/netflix if we alot time for personal projects then it can help you a lot in the long run.