Why Basements Flood — Top 5 Reasons

Etobicoke's older lateral sewers and clay soil make basement flooding a recurring headache. Here's what actually causes it.

Common causes

• Municipal sewer backup during heavy rain
• Failed or absent sump pump
• Cracked foundation wall or window well overflow
• Downspouts discharging next to the foundation

Step-by-step

1. 01Install a backwater valve on the main sewer lateral
2. 02Add a battery backup to the primary sump pump
3. 03Extend downspouts 6+ feet from the foundation
4. 04Seal window wells and foundation cracks

When to call Northbridge

• Any past basement flooding event
• Home built before 1980 with original sewer lateral
• Insurance requires flood mitigation for renewal
• Finished basement with no backwater valve