Why Flat Roofs Leak: Details Worth Checking First

What to check first

• Inspect transitions before blaming the entire membrane.
• Look for water entering through an adjoining wall.
• Check the roof assembly for moisture when leaks keep returning.

Build a repair plan from evidence

1. Record the pattern

   Note the indoor location, timing, rain direction, and whether water appears after the rain has stopped. Photos and a simple sketch help compare the symptom with the roof above.

2. Inspect the likely entry points

   Check visible seams, flashing terminations, penetrations, drains, and wall details. Water can travel within an assembly, so the area directly above a stain is only a starting point.

3. Match the scope to the damage

   A sound, dry surface with one confirmed defect may suit a localized repair. Wet insulation, soft decking, or repeated failures need investigation before another surface patch.

Watch the field examples

These archive demonstrations show individual projects. Use the current guidance above and Bergstrom’s published instructions if an older video shows a different product or method. Torch work shown in installation videos is professional work.

From the project archive