Foam Roof and IR

Specific Inspection Topics Thermal Imaging, Infrared Cameras & Energy Audits
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I got a call about possibly doing an IR scan for a roof of an industrial building from roofer. I agreed to meet at the location just to get a better feel of the issue and the scope of the project.

It turns out to not be a flat roof (the address given to me was off by a number, so I had looked at the roof across the street on google), but a pitched metal roof with foam roofing.

The issue of concern is despite numerous repairs, there are certain points of the roof that leak on a regular basis.

Per the roofer, there have been 3 layers of foam applied over a 35 year period, but the coating has not always been kept up prior to him taking over. He suspects there is water trapped in between the layers.

I didn’t take any IR pictures (yet) and we agreed that moment was not the best time to do the work (there was some ponding water in the valleys from recent rains that would give an obvious false reading).

I did pull out my camera just to see if there was anything blatantly obvious.

Scanning from below was pointless, due the steel beams, pipes and duct work.

Scanning from on the roof was difficult due to the glare of the sun on the screen. But I did notice I could easily see the ridges of the metal roof through the 3 layers of foam.

I also noticed any shadow on the foam (from the AC condensers, etc) made a HUGE difference in temperature reading of the foam itself (more so than other roofing materials) which has me concerned if even if I came back after sun down, would the shadows still read cold? Or would the foam even out quickly with no sun?

Has anyone does IR scans of a foam roof?

Should I use the same protocol one would use on a flat roof material, or this really a different approach?

Is IR just overkill on such a material? It almost seems like using my moisture meter would be more useful.

Any thoughts, comments, articles, appreciated.

Thank you.

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Ian,
I have done several foam roofs. Imaging process is basically the same as any other roof but sometimes both night and am images are necessary to verify moisture if you don’t have a RWS moisture meter to help.
Here are AM images of moisture in foam roof.

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Dear Ian:

The topic of Infrared Inspections of Roofs Containing Foam Insulation <IRINFO - Tip of the Week Archive 2012 July-Dec > was the subject of a recent Tip of the Week at our content-based website, IRINFO.ORG. This Tip and hundreds like it make be accessed for free.

Infrared inspections of spray-applied foam roofs are conducted in the same manner used to inspect insulated built-up or single-ply roofs. Walk-over inspections should be performed post-sunset following a sunny day.

When performed under such conditions, wet insulation will cause amorphous warm areas which may range in size from a few square inches to thousands of square feet. Depending upon the condition and size of the roof, you may find evidence of hundreds of discrete wet areas. Because an infrared imager does not detect moisture, invasive testing should be performed to confirm the presence of suspected moisture within the insulation.

It will not be possible to accurately inspect areas of roof that are wet or under water at the time of the inspection since an infrared imager will not ‘see’ through standing water.

For more information on this subject, you may wish to obtain a copy of the Standard for Infrared Inspections of Insulated Roofs. Copies of the Standard are available online at the following URL: <Standard for Infrared Inspection of Insulated Roofs - 2011 Edition - Infraspection Institute Online Store

Hope this helps.

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Thank you.

Thank you.

5

Sounds like you got good advice on IR inspections. But is water actually a problem?

Of course water is heavy, so that can be a problem.

On a foam roof, evidence of water trapped is bubbling of the elastomeric coating on hot days. The coating is super stretchy, and will take quite a bit of force (the bubbles may be water tight).

I’ve seen saturated foam, and it can be quite localized. It’s closed cell foam and the water just hardly moves through it in any direction.

It is not normal to have layers of foam applied over years. It is more normal to have a few layers of original foam, then periodic layers of additional coating. Roofing rocks are used by some foam roofers (they are used, as in shingles, to absorb UV light).