Flat Roof Leak Diagnosis Checklist
Use this checklist to organise what you can safely observe before deciding whether a flat-roof problem is suitable for a local repair or needs professional investigation.
1. Note when the leak happens
- Only during heavy rain?
- After wind-driven rain?
- After water has ponded on the roof?
- Continuously after a storm?
See leaks after heavy rain and storm-related leaks.
2. Check the internal position
Record where staining or dripping appears, but remember water can travel before it becomes visible indoors. See how to find a flat roof leak.
3. From a safe position, look for obvious defects
- Cracks or splits
- Open or failed seams
- Damage at edges or trims
- Problems around rooflights
- Defects at walls and upstands
- Blocked or damaged outlets
- Damage around pipes or penetrations
- Blisters or bubbles
- Ponding water
4. Check whether the problem is local or widespread
A clearly local defect with sound surrounding material is different from widespread cracking, multiple failures, sagging or a soft deck. Use the repair or replacement guide.
5. Identify the roof material
Use the relevant guide for GRP fibreglass, EPDM rubber or felt roofing.
6. Decide whether local reinforced repair is appropriate
Read is a liquid flat-roof repair right for my roof? and reinforced repair vs coating only.
7. If the defect is suitable
View the SealForge Reinforced Flat Roof Repair Kit, which combines polyurethane liquid rubber, separate fleece reinforcement, primer, catalyst and application tools.
Safety: Do not climb onto a wet, icy, fragile or unsafe roof. If safe diagnosis is not possible, use a competent roofing professional.