Detecting a roof leak early is critical for avoiding water damage and costly repairs. Here are some basic techniques to determine whether your roof has a leak:   Check for Water Stains: Look for discoloured spots or streaks on your ceiling or walls, particularly after heavy rain. Inspect the attic or crawlspace for showing of water entry, like moist insulation, stains on the rooftops, or puddles on the floor. Look for Mould or Mildew: Mould or mildew growth may indicate excess moisture from a roof leak. Check for leaking or Puddles: During or after a rainstorm, look for leaking water or puddles within your home. Inspect the roof exterior for missing or damaged shingles, cracked flashing, and blocked gutters. Check for Sagging locations: Look for locations where the ceiling or walls appear to droop, which might indicate water damage. Use a Flashlight: On a wet day, check your attic or crawlspace for evidence of active water penetration. Monitor During Heavy Rain: Keep an eye out for unexpected leaks or evidence of water penetration while it rains heavily.