Do stains on the ceiling mean the roof is leaking?
Sunday, October 21, 2018
Maybe...or maybe not. The first thing we try to determine with a ceiling stain is whether it was caused by a roof leak or some other problem, such as a leaking air conditioning condensate-water drain line in the attic. If we conclude that a roof leak is the culprit, then the next question is: active leak or previous leak?
If the home has a newer roof, then we might be looking at the problem that caused the homeowner to recently replace the roof. Perhaps they just haven’t repaired the ceiling damage/staining yet. Further investigation in the attic and on the rooftop itself will give us a clearer picture of what’s happening.
One of the first tools we pull out for this puzzle is our infrared camera. A visual tool that sees heat instead of light, the infrared easily recognizes wet areas because the evaporation of the moisture cools the surface in the area of the wetness. And a wet area at the staining is an indication of an active problem. If the infrared camera sees signs of moisture, then we use another tool called a moisture meter to verify and measure how much water is in the material.
But a dry area is not necessarily an indication of an issue that has already been repaired: if the cause is a roof leak, and it has not rained recently, then it is possible to have an active roof leak but no moisture at the time of testing.
Looking up at the area directly above the stain in the attic tells us more about what’s happening; then, checking the area of roofing above that for defects that would cause leaking is next. Because the water in a roof leak doesn’t always fall directly down from where it penetrates the roof covering, sometimes even more probing is necessary. A roof leak can migrate downward between the roof covering and roof sheathing before it enters the attic, then run down the surface of roof framing lumber before it finally falls onto the ceiling.
But eventually we track down the problem and recommend a solution for you.
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To learn more about roofs and attics, see these other blog posts:
How To Look At A House
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