How to find where a roof leak is actually coming from
Water travels along framing, pipes, and angles before pooling in a ceiling or insulation, meaning the drip spot rarely sits directly below the entry point. Tracing the path requires opening up walls or tracking water back to penetrations like pipes and concrete patches where moisture seeps through seams far from where it appears inside.
What the numbers show
Counted from the threads quoted below. How we count
- The most recent one is from October 2026.
- This comes up 41.3× more often in r/Roofing than across the site as a whole.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1Inspecting the attic insulation and framing to trace water flowDid this help you?
- 2Inspecting exterior flashing and shingles for gaps or missing componentsDid this help you?
- 3Asking online communities to analyze photos of the roof and atticDid this help you?
- 4building an insulated box to manage condensationDid this help you?
- 5using UV water-based tracer to locate the leak pathDid this help you?
- 6sealing the inside temporarily with marine sealantDid this help you?
- 7lifting the entire roof to have it redoneDid this help you?
- 8cutting a patch out of the drywall to inspect the areaDid this help you?
- 9accessing the roof to check for clear answersDid this help you?
- 10ordering a new rain collar for the pipeDid this help you?
- 11Insulating the ductwork with board foam and glueDid this help you?
- 12Removing screws to look behind the installation boxDid this help you?
- 13Tracking down the hidden furnace to inspect componentsDid this help you?
- 14holding a hose over the skylight to test for leaksDid this help you?
- 15applying sealant around the skylightDid this help you?
- 16pouring multiple layers of chemical rubber over the flat roofDid this help you?
- 17Getting on the roof or into the attic space during active rainDid this help you?
- 18Removing siding to inspect flashings and weather sealsDid this help you?
- 19Trying to seal lifted shingle tabs or repop nails with roof adhesiveDid this help you?
- 20Inspecting the flashing around windows and sidingDid this help you?
- 21Looking at the underside of the roof from below to trace the entry pointDid this help you?
- 22Applying roofing tar to hold down lifted tabsDid this help you?
- 23Calling numerous contractors to inspect the roofDid this help you?
- 24Inspecting potential trouble spots like flat roof sections, valleys, dormers, and penetrationsDid this help you?
- 25Adding metal valleys or ice and water shield membranesDid this help you?
- 26Trying to diagnose and troubleshoot potential entry points independentlyDid this help you?
- 27Applying sealants or adjusting flashings and caps manuallyDid this help you?
- 28Leaving ant poison to rule out pest-related damageDid this help you?
- 29putting roofing tar along the flashingDid this help you?
- 30Testing with a roof sprinkler and tracing inside the atticDid this help you?
- 31Applying caulk to suspicious areasDid this help you?
- 32going up on the roof to investigateDid this help you?
- 33cutting a hole in the ceilingDid this help you?
- 34installing bathroom ventilationDid this help you?
- 35Checking if the wet spots dry out after the rain stops to differentiate between condensation and a roof leakDid this help you?
- 36Inspecting if the drops are hardened sap from the woodDid this help you?
- 37Considering whether to attempt the repair independently or questioning if the repair should be made again by the same contractorDid this help you?
- 38Calling various specialists such as roofers, plumbers, handymen, AC technicians, and mold remediation specialistsDid this help you?
- 39Excavating buried drain linesDid this help you?
- 40Calling a roofer to inspect and repairDid this help you?
- 41Inspecting the roof personally and taking photosDid this help you?
- 42Replacing the vent pipe bootsDid this help you?
- 43Sealing holes in shingles with aluminum sheets and roofing cementDid this help you?
- 44Running water directly down the drain using a hose to isolate the drain connectionDid this help you?
- 45Calling a plumber for inspectionDid this help you?
- 46checking trim and J channel installation for proper water drainageDid this help you?
- 47removing interior trim and cutting back drywall to trace the leakDid this help you?
- 48inspecting roof drip edges and closures for gapsDid this help you?
- 49inspecting the attic for active dripsDid this help you?
- 50looking at the roof from ground level for missing shinglesDid this help you?
- 51Adding an extra downspout near roof valleys to prevent gutter overflow during heavy rainfallDid this help you?
- 52Inspecting the attic directly to locate signs of water entering through the roofDid this help you?
- 53Checking roof valley returns and low-slope roof connections for active leaksDid this help you?
- 54Inspecting seams, curbs, and drip edges for holes or separationDid this help you?
- 55Trying to trace the leak from the attic spaceDid this help you?
- 56Inspecting the roof exterior for pooling waterDid this help you?
- 57Posting photos online for visual diagnosis by expertsDid this help you?
- 58Posting photos and asking for preliminary advice on online forums before contacting professionals.Did this help you?
- 59Hire a professionalDid this help you?
- 60replace everything that touches that valleyDid this help you?
- 61Follow the dirtDid this help you?
- 62pulling some sheetsDid this help you?
- 63Catching the drips with a pinched funnel and a bowlDid this help you?
- 64Applying excessive caulk around the roof bootDid this help you?
- 65Installing screw caps on every single roof screwDid this help you?
- 66Putting a cover and vented cap over the pipeDid this help you?
- 67Checking potential roof penetrations near the water intrusion like ventsDid this help you?
- 68Inspecting the roof exterior above the leak area in daylightDid this help you?
- 69Did a quick tar patch while we get quotesDid this help you?
- 70covered the seams as much as a gallon would get meDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“I spent 2 grand to have this fixed and it's leaking again and nobody will come out to even look at it, called 12 places.”source ↗
“Had a duct vent that was leaking and bled through my ceiling. First time they came they said they never sealed it, month later leaked and bled through the ceiling again. Their solution this time was to do the same thing.”source ↗
“Bought a brand new home 4 years ago. Look in the garage and see mold on the wall/ceiling corner.”source ↗
“What should I be looking for to determine if its a repair or replacement?”source ↗
“The shingles underneath are getting wet in the valley. I can't find the source of the leak, but when it rains it's a decent sized leak.”source ↗
“The issue is we have a PERSISTENT leak in the corner of the skylight and cannot work out where it’s coming from.”source ↗
“As I type this roofer is vowing to come back with his joiner and he will not stop until he fixes this - we trust him, honestly, he’s a good guy and persistent, but we’re all fatigued from looking at this problem.”source ↗
“my bathroom has had a drip in the ceiling that became a full fledged leak in these last rains? i have included the approximate position of the leak and can’t find any damaged shingles? this makes me think it may be along the flashing?”source ↗
“Some water is coming through the window frame on the inside.”source ↗
“Does this look like it could be the problem? Or should I keep looking for possible leak spots.”source ↗
“Help me figure out where this leak is coming in.”source ↗
“Wife calls me - our sons bedroom is leaking from the ceiling.”source ↗
“Immediately see the water in the insulation directly below where the angle down begins.”source ↗
“Literally no way to know without getting on the roof or in the attic space when it's actively leaking.”source ↗
“The problem with leaks is that they can be a long distance from where you actually see the water coming through inside the house.”source ↗
“Hi, this area it’s wet. We had a big storm come in in Texas and the rest looks dry but this specific area the brick is wet.”source ↗
“Recent AZ rain has exposed a weakness in the roof. Yet I can’t tell where it is coming from.”source ↗
“A couple roofers have just said roof needs replaced cause it’s 27 years old yet haven’t identified leak point.”source ↗
“Recently our roof sprung a leak, same place, slow drip, we opened up the wall and found the bottom of this pipe, and the square infill of concrete to be weeping at the seams, water is coming between the outside of the pipe and the concrete patch in the roof.”source ↗
“Satisfied that the leak presents at the pipe but seems to come from somewhere else, it's not a "local" repair, I gaffed up the inside with Sika marine sealant and called it good.”source ↗
“Sorry, I'm pretty new to the correct terms and whatnot.”source ↗
“The roof is mixed slate at a steep pitch and flat bitumen. The flat bituman was replaced last year which we thought would put this to bed finally, but still we see some moisture and leakage.”source ↗
“No attic for me to be in unfortunately.”source ↗
“I noticed a spot in our bathroom that would indicate some type of water damage.”source ↗
“My first concern is whether these exhausts/pipes should be capped in some way. Could this cause a leak?”source ↗
“I was hoping that is something in that division between floors… as I you said I check the trim of the door and is dry but the J channel that hold the siding on top into the second floors don’t have the holes that you mentioned (the manufacturer recommended in a video) Do you think that I should drill the holes and test before open the siding?”source ↗
“Does anyone know where I can get a water leak detector? I need to know where the water is getting in at so I can direct the roofer where to fix.”source ↗
“want to know if anyone has a method to identify leaks or find where the water protrusion is coming from.”source ↗
“The downspout is on the end far left from picture. It’s weird only the brick is wet”source ↗
“With Rubber EPDM, it’s easy to get a leak especially around any curbs.”source ↗
“Looks like it’s comming from around the drip edge. the seam in the middle of the photo is factory rubber seam. That’s not leaking Looks for holes just in case”source ↗
“The AC duct prevent me from getting to the leak, but judging by the location on my ceiling I think its coming from a weird intersection on my roof the has about a 1/4 inch deep pool of water during light rain (see pic).”source ↗
“Does it look like the roof was not done properly to prevent leaks?”source ↗
“It’s raining today and I happened to notice a small leak in my attic.”source ↗
“I know basically **nothing about roofing**, so assume I’m an idiot here.”source ↗
“Is this usually a relatively simple repair, or could it indicate something more significant?”source ↗
“I’m mainly trying to figure out what I’m dealing with before I start calling roofers and sounding like an idiot.”source ↗
“We don't have an attic. It's an old house so the shower ceiling is sloped for the roof.”source ↗
“This is driving me up a wall, so I have decided to see if anyone has any ideas as to how this leak may be occurring.”source ↗
“I couldn’t find any indications of cracking in the boot, but nothing made sense to me, so I caulked the absolute shit out of it, put a cover over the whole pipe, and a ventted cap, yet I am still getting the leak.”source ↗
“I have ran a hose on the boot for quite a while and it does not leak.”source ↗
“We had a roofer, plumber, 2 handy men and an ac specialist come out... multiple times. No one could figure out the leak.”source ↗
“I just dont even know who to call at this point?”source ↗
“First time homeowner here. I dont have a dad or grandpa to ask this sort of question. I can't tell if this is from the shower or if there's a leak in the roof.”source ↗
“Paint started to bubble, and I went up there and started poking and my finger went right through.”source ↗
“Kinda stumped at what steps to take.”source ↗
“I cut a patch out of some drywall that was showing a wet spot, it would happen during heavy rains”source ↗
“I was wondering if it looks like it is from the vent pipe and if the wood looks ok still?”source ↗
“i ordered a new rain collar for the pipe, would that help at all?”source ↗
“Hi All, first time home owner and not really in a position to hire someone, especially when I know I'm capable (although perhaps a bit nervous to do). I noticed some water damage on my sunrooms ceiling today, and I'm trying to source where it's coming from.”source ↗
“We have had some pretty heavy rain and wind lately. I'm starting to think i may be I'm over my head with this”source ↗
“Looked in my attic during a heavy rain and saw the “knot holes” in the board right in the front were wet? Not dripping but like they were sweating. Couldn’t see it anywhere else but who do I call now?”source ↗
“Ceiling stain below upstairs tiled shower, only wet after showers. What's the likely cause?”source ↗
“This contraption will drip water after we run the AC for a while, was told by someone else that this is very shoddy work.”source ↗
“I'm assuming its more difficult to figure out whats exactly wrong because you cant see inside and that leaves the quote up for debate?”source ↗