[header] How to get rid of rats in apartment buildings [title] Use wooden snap traps. [step] You will need to make sure that your traps are big enough for a rat. You can buy larger traps or make the trigger of a small trap bigger by attaching a 2-inch (5 centimeters) piece of cardboard to it. 
The cardboard will trigger the trap if a rat steps on it. [substeps] You can also try a wooden snap box trap, which is better for outside.