Why does a blocked dryer vent cause fires?
Since homes today tend to be larger than in earlier days, dryer vents also tend to travel for longer distances. This provides more area for lint to gather and to become trapped. Though there are lint traps in clothes dryers, a considerable amount of lint will still escape through the trap and accumulate within the vent. Also, if there is inadequate space between the wall and the clothes dryer, the dryer can crush the material of the vent, which will further reduce the vent’s efficiency. When your dryer vent is blocked by lint, the combination of reduced air flow and the higher temperature at which the clothes dryer is forced to operate can lead to accidental fires.