Signs the source may be external
If damp appears after rain, near a roof, below a terrace, around a balcony door or close to drainage points, the source may be waterproofing or rainwater movement rather than a pressurised pipe.
- Damp after rain
- Staining below terrace
- Blocked or poor drainage
- Cracks or failed waterproofing details
How diagnosis works
The inspection considers timing, building layout, visible defects, moisture spread and thermal patterns. The goal is to show whether plumbing, drainage, waterproofing or roof details should be investigated first.
- Compare rain timing with symptoms
- Check terrace and drain routes
- Map moisture internally
- Document likely next steps
Why it matters
Treating terrace ingress as a pipe leak can waste money. Treating a pipe leak as a waterproofing issue can let damage continue. The value is in separating the possibilities with evidence.
- Avoid wrong repair scope
- Protect internal finishes
- Clarify contractor responsibility