How to Inspect Your Flat Roof - 7 Tips for DIY Flat Roof Inspection
Jens Johanson
Building Envelope Consultant | The Building Doctor, J2 Building Consultants | Helping condo owners restore their sick buildings (WA, OR, UT)
1) Interior staining: start by looking for evidence of interior staining. Look at your ceiling and ceiling tiles. Do you see brown or yellowish water spots? Is the ceiling paint starting to bulge? This could be a symptom of a leak above.
2) Soft spots: Up on the roof, pay attention to your feet. Check out valleys where debris is collected, is the roof material a bit spongy and soft? This could be a sign of failure.
3) Patches: Is your roof starting to look like a patchwork quilt from a long history of repairs? When you start to see more patches than original roof, it may be time to consider a replacement.
4) Penetrations: Look for every fold and seam in the roof membrane around pipes, vents, and corners. Each penetration is another possibility for water intrusion. A quick test for these penetrations is to poke around with a small nail file to check for sealant failure.
5) Drains: If your primary roof drain is clogged with debris, your roof overflow drain will kick into action. There's usually a pipe that spouts out the side of the building to empty the overflow drain, which means you won't see water coming out of that pipe unless your primary drain is clogged!
6) Sealants: If you have sealant on metal joints, the metal can expand/contract and cause the sealant to fail.
7) Reverse Lapped Repairs: Sometimes temporary repair patches are adhered onto the roof without consideration for water flow. This can cause your roof patches to collect runoff and fill up with blisters of water.