Why do drains get blocked?

Drains can get blocked for many reasons. These are the most common causes of a blocked drain:

• Flushing objects that won't easily pass through your drain.
• Overloaded or undersized pipes restricting the ability to drain freely.
  
• Fractured or deteriorating pipes.
  
• Tree roots invading the drain.
  
• Drain misalignment.
  
• Fat, oil or grease build-up.
  
• Hair build-up.
  
• Scale build-up.
  
• Waste food.
  
• Natural objects such as leaves, dirt, rocks and even small, dead animals.
  
• Cement or plaster that may have been flushed into that drainage system from building works.