We get calls all the time about water leak detection problems that vex our customers. Many are routine but the unique ones where we can bring Indigo® Expertise™ to bear are particularly gratifying. One of those calls, from Alan W. of Carollton, Ohio was interesting enough that we asked him if we could tell his story & here it is in his own words (mostly).
The Problem: Leaking Roof
Customer: I have an antique barn with a gable style roof installed over insulated SIPS panels 5 years ago. A year after installation I noticed staining at the ridge of the ceiling. We discovered water infiltration after certain rain conditions. I THINK we solved it but I’m not sure because sometimes it seems like the stains change darkness after certain rains.
The peak of the ceiling is over 30′ above the floor so it’s really difficult to examine in person. Would one of your leak detection paper products work in this application? I’m looking for something that I can tape onto the stained area (OSB board) and examine with flashlight and binoculars from the floor to look for any new leakage.
It needs to permanently change color, even after it’s dry, because I may not check the roof for weeks after it rains. The moisture would have to soak through the back of the paper and change color on the front of the paper so that I can see it from the floor to be useful in this application.
It would also have to be sensitive enough to wick moisture off the OSB only if taped or pinned at the edges and with gravity working against it, trying to pull the paper off the ceiling.
Water Leak-The Solution
Indigo: The cobalt chloride test paper sheet is generally best but it is reversible so probably not the best for you. The chlorophenol red test paper has the most dramatic change but it is pH-dependent. Any rain that is more than mildly acidic will not cause a color change. The universal pH test paper could work but if the pH is only slightly acidic or alkaline, the color change would be hard to see from 30 feet.
Perhaps the best solution is the 3 piece sample pack. Cut each sheet into strips of lengths & widths of your choosing & then tape them together as ABC-ABC-ABC, etc. & attach them to the area in question. This will improve your odds that at least one of them will show the leak.
This call came to us on a Saturday afternoon but we monitor our e-mail even on weekends.
Customer: Thank you for your phenomenally fast and helpful reply. I’ll order a couple sample packs right now!
Water Leak Problem-Revisited
Of course, problems & solutions are rarely solved so easily so when the customer had some follow-up questions, we put our thinking caps on once again.
Customer: The best scenario, though, from my perspective is that there is never any change in the paper over a year or more meaning that the leaks are gone.
How much of the paper will need to be in contact with the surface and how closely? Does the paper wick moisture any distance?
Indigo: Can you place the paper & then soak the roof with a hose? The paper is pretty absorbent & there would be some wicking but you should still be able to determine the points of ingress. The best results are if the paper is in direct contact with the roof section that is leaking.
Customer: No, I have no water nearby. I’m just going to have to wait for rains from different directions. Easterly rains are the likely culprit (if there still are leaks) and those are relatively rare so this could take some time. I’ll let you know if anything happens.
As luck would have it, the rain came sooner than later & the worst-case scenario presented itself. The customer obliged us with photos.
Customer: You may recall that I was looking for a solution that would allow me to monitor the potential leaks from 30′ away so that I didn’t have to keep resorting to ladders. Here is how I used your water leak detection sheets.
The first photo shows my attempt at tracking the moisture via marking the outline with a magic marker. It didn’t allow me to know if the area was wet but not growing, though, so was relatively useless.
Note the black magic marker outlining the small section of the roof that has water damage.
Customer: The second photo shows the paper about 15 minutes after I installed it. The middle one was already starting to change so I pretty much knew right then that I still had an active leak. The wood wasn’t wet to the touch but apparently was moist enough that the paper indicated where the leak was occurring.
Left to right: universal pH leak detection paper, cobalt chloride water leak detection paper & chlorophenol red leak detection paper. Each has its advantages/disadvantages.
Roof Water Leak Detected!
Customer: The third photo is 5 days later showing the significant color change. It’s not a great photo; I took it from the floor of the barn whereas the first 2 were up at the ceiling.
Chlorophenol red on the left shows a boundary between wet & dry areas. The cobalt chloride white area was wet along the bottom half but the purple-blue top was not. The right side universal shows some spotting but pH was just acidic enough not to cause a contrasting color change.
Customer: The last photo was “control” strips which I had placed on an area that I was pretty sure was not leaking. I wanted to know whether the paper was going to change color just from ambient humidity. It didn’t (or at least didn’t much).
These water detection sheets are in a control area & show no wetting.
Customer: After I try (again) to repair the roof I’ll try the tests again and I’ll probably try to use a staple gun instead of push pins that time.
Thanks for your advice and for offering a product that was helpful to me.
Leak Detection-Water & More
Water is by far the greatest nuisance in terms of leakage but it’s not the only one. Here is more information on the various Indigo® test papers and what they can detect or measure.
- Find Water Leaks Fast: Cars, Boats, Roofs, Plumbing. Lots of places & things where water gets into trouble.
- Ammonia leak detection cloth. The cloth finds very tiny air leaks in “gloveboxes”. These are important in a variety of applications including the pharmaceutical & radioactive materials industries among others.
- Ammonia-phenolphthalein test papers. Ammonia’s use as a refrigerant has increased greatly over the last few years as chlorofluorocarbons use has been restricted or banned. It’s popular in the food industry as well as skating rinks. These simple test strips can identify leaky joints in the refrigerant piping. Our blog: Ammonia Leak Detection Methods: pH Paper vs Cloth & goes into greater detail.
- Lead acetate test paper for hydrogen sulfide detection. Hydrogen sulfide has the familiar “rotten eggs” smell and can be toxic in quite low concentrations. The test strips can be wetted to detect airborne H2S or dipped in water where bacterial sources are suspected.