How to locate roof leaks


[Editor’s note: This information is provided by roof membrane manufacturer Dicor. While there may be plenty of “promotion” for their product included, some of the information and principles may be of assistance to our readers.]

Being careful, get on your roof and feel around. Soft spots can indicate loose roofing material and damage to the substrate, composed of anything from 1/4-inch lauan to 3/4-inch plywood layered over trusses. Structural integrity can be seen by looking for low spots or ripples in the roofing, which means the roofing material or substrate is failing. That can lead to cracked substrate and areas of depression where water can pool and eventually cause further damage and leaks.

With rubber roofs (EPDM or TPO), look for areas that may be swollen or uneven in thickness, including the “ripple effect.” Cleaners that use petroleum distillates (including many household cleaners) can loosen the roofing material from the substrate, compromising the roofing’s integrity and making it more vulnerable to damage.

Check for punctures and cracks and areas where they’ve been patched. See if the patches are well sealed: push on them to feel any softness underneath which means there’s damage that could worsen.

CHECK THE SEALANT around the edges and around skylight hatches, antennas and other objects that stick out of your roof. See if the sealant is cracked or loose (can you pull some of it off?) or curled at the edges — a prime source for leaks. Also, look for dirt streaks heading underneath seals in low spots. If you pull on the loose sealant and the dirt continues underneath then water is probably getting past the sealant and might have caused water damage in the structure.

Regular inspections can help you identify a problem when something “looks different” from your previous inspection and can prevent leak problems before they cause costly damage.


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6 months ago

A visual inspection is good but will not necessarily locate the leak(s).
A leak can be at one place on the outside and travel to an entirely different place inside. An easy way to find leaks is to pressure test the coach/trailer.

Basically, while you pump air into the closed vehicle with a blower or fan, spray the outside seams with soapy water. You will see bubbles where the leaks are. And, not just on the roof but at seams, vents, and around windows.

6 months ago
Reply to  JBurt

I should have included the entire roof in the soap check. It needed to be washed anyway. Right?

Stephannie Doyon-Peterson
1 month ago
Reply to  JBurt

Interesting idea. We have a leak and can not find it all. A few times when it has rained we have seen water come in over our door. So yesterday we went around to all the stuff on top, the awning, and even the trim and put a hose over it and still couldn’t get it to leak. We even tilted the RV different ways.