How long does it take for blood to dry up?

Okay I'm new here. But I need help with this. Every morning before I go to work there's splattered blood on my door on the same spot every morning. By the time I leave to work, the blood 'splat' is sorta dry but da blood that dripped down the door is still wet. I want to know how long the blood might of been sitting there on my door? Thanks.