Water gets into a home through the roof, but it also gets in at a window opening, a siding lap, a sealant joint or a soffit and fascia junction, and it travels along framing and decking before it ever shows up inside. Tracing a leak correctly means following that path back to the actual entry point across the whole exterior, not patching the spot above the stain. Our in-house Red Seal crews trace, document and scope it in writing.
Water follows the path of least resistance, not a straight line down. Once it gets under a shingle, behind a siding lap, past a window seal or through a flashing gap, it runs along the sheathing or roof decking, drips onto the top of the framing, and travels along a rafter, a truss chord or a wall stud before it finally finds a gap in the insulation or drywall to show through. By the time you see a stain, the water has often moved sideways several feet, sometimes more, from where it actually entered the building. That is exactly why tracing a leak from the interior stain alone gets it wrong so often, and why the repair has to start with finding the real source on the roof or the rest of the envelope, not the visible symptom.
Once inside the roof assembly, water travels along rafters, trusses and decking rather than dropping straight down, often carrying it well away from the entry point.
On a pitched roof water runs downhill along the deck before finding a gap, so the entry point is almost always upslope from where the stain appears.
It can take repeated rain or melt cycles for water to travel far enough to show through drywall, so a stain often only appears well after the leak itself started.
Not every leak announces itself with an obvious drip. Many show up first as something easy to dismiss. If you recognize more than one of these, it is worth having the source traced before it gets worse.
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A leak investigation is only as good as the person reading the building. Our in-house Red Seal crews trace leaks across the same roofs and exteriors they build and repair, so they know what a lifted flashing, a failed seal, a siding lap or an ice-damming pattern actually looks like from experience, not a checklist. Backed by COR safety certification and $10M liability coverage.
Finding the real source before repairing anything. Every step carried out in-house by our certified team.
Flashings at chimneys, walls, valleys, window heads and roof-to-wall junctions are where the building envelope breaks, and breaks are where water gets in. We check every flashing detail on the elevation the stain points toward before assuming the field of the roof itself has failed.
Water that enters near the eave often travels along the underside of the deck before it drips through the ceiling, which is exactly why the stain never sits above the actual entry point. We follow the staining pattern on the deck itself to trace it back toward the source.
Vent boots, pipe collars and any fixture that penetrates the roof or exterior wall rely on a seal that ages faster than the material around it. We check every penetration and caulking joint on the affected elevation, since a failed seal the size of a coin can be behind a stain that spans a whole ceiling.
Once the source is traced, you get it in writing: photos of the entry point, an explanation of how the water travelled from there to the stain, and a scoped repair, not a verbal guess you have to remember correctly for an insurer later.
The field of a shingle or membrane rarely fails on its own, and neither does the rest of the exterior. Almost every traced leak comes back to a detail: a flashing lap, a window or door opening, a siding joint, a penetration, or a seasonal pattern like ice damming. That is why we check these first rather than assuming the worst about the roof alone.
The single most common source of a traced leak. Flashing that has lifted, corroded, or was never lapped correctly in the first place lets water in exactly where two roof planes, a roof and a wall, or a wall and a window head meet, often a long way from where the stain eventually shows up inside.
Every pipe, vent and fixture that comes through the roof relies on a seal, and that seal is usually the first thing to fail on the roof, well before the shingles around it show any wear. A cracked vent boot or a bead of sealant that has dried out is an easy thing to miss from the ground.
Every window and door is a cut made in the envelope, sealed at installation with flashing and a bead of caulking around the frame. Once that perimeter seal ages or a corner lifts, water tracks in along the frame and can travel well past the opening before it shows on the wall or ceiling below.
Siding sheds water by lapping downward, so a panel that has lifted, a cut edge left unsealed, or a gap where siding meets the soffit and fascia at the roofline gives water a way behind the cladding. Eavestrough and drainage issues at the same junction can push that further.
Meltwater refreezing at the cold eave backs up under the shingles and finds its way in above the fascia line, a pattern that looks nothing like a flashing leak and gets misdiagnosed often. It traces back to heat escaping from the attic below, which is why we check attic insulation and ventilation whenever the pattern points this way.
A roof or an exterior wall often has more than one of these developing at once, which is why we trace the whole affected area rather than stopping at the first thing we find.
The physics are different, so the tracing method is different too. Here is how we approach each.
Gravity-fed tracing
Water runs downhill along the deck once it gets under the shingles, so we trace upslope from the interior stain toward flashings, valleys and penetrations on that same plane, checking each in turn until the entry point is found.
Membrane & drainage
Flat roofs fail differently: water can pond and find a seam, a drain or a membrane puncture anywhere across a much larger area, and gravity gives fewer clues. We trace along the drainage path and inspect seams, penetrations and low points rather than assuming the stain sits directly below the fault.
Highest leak risk
Every valley, dormer and change in roof plane is another place two roof sections have to be flashed together correctly, and every one of those transitions is a possible source. Complex rooflines take longer to trace precisely because they give water more places to travel before it finds a way in.
A small, traceable leak rarely stays small. The longer water has access to the roof or wall assembly, the more of the structure and finishes underneath it can reach.
A few simple steps limit the damage inside while the source gets traced properly. None of them fix the roof, and none of them are a substitute for having it traced, but they buy you time.
Place a bucket or container under an active drip, and if you can safely reach the attic side, a tarp or plastic sheeting under the wet area can catch water before it spreads further into insulation and drywall.
Write down when the stain appears: during rain, right after, only in wind from a certain direction, or with the spring melt. That pattern is genuinely useful information when we trace the source.
A wet or icy roof is genuinely dangerous to walk, and climbing up to inspect it yourself risks a fall and can make the damage worse. Leave the roof-side tracing to someone equipped and trained for it.
A leak trace goes well when the diagnosis comes before the repair. Here is exactly what to expect.
Tell us where the stain is, when it appears, and whether it tracks with rain, wind direction or the spring melt.
We look at the stain itself, its shape and location, for the first clues about where water is travelling from before we ever get on the roof.
We work from the interior clue outward, systematically checking flashings, penetrations, valleys, window and door openings, siding laps and the attic side in the order most likely to reveal the source.
Whatever we find, entry point, suspect areas or the path water travelled, gets photographed, so you have documentation rather than just our word for it.
You get a clear, written repair scope for what was found, with no pressure to decide on the spot.
Because water rarely drops straight down once it gets under a shingle or through a flashing gap. It runs along the roof decking, drips onto the framing, and can travel several feet along a rafter, truss chord or sheet of decking before it finally finds a gap in the insulation or drywall to show through. That is why tracing a leak from the interior stain alone gets it wrong so often, and why we start by reading the stain for direction, then trace the roof and attic outward from there.
We start with an interior read, the shape, location and pattern of the stain, before we ever get on the roof. From there we trace outward, checking flashings, valleys, penetrations and vent boots on the affected slope, and looking at the attic side for staining patterns on the decking itself. The entry point and the path the water travelled get photographed, so the finding is documented, not just our word for it.
Flashings and valleys, where two roof planes meet, are the single most common source, followed closely by failed seals around penetrations like vent boots and pipe collars, which are often the first thing to wear out well before the shingles around them show any age. Ice damming at the eave is a common winter-specific cause that traces back to heat escaping from the attic rather than a fault in the roof surface itself.
Yes. On a pitched roof, water runs downhill along the deck, so we trace upslope from the interior stain toward flashings, valleys and penetrations on that same plane. A flat or low-slope roof behaves differently, water can pond and find a seam, drain or membrane puncture anywhere across a much larger area, so we trace along the drainage path and check seams and low points rather than assuming the fault sits directly above the stain.
Contain the water with a bucket or container under the drip, and if you can safely reach the attic side, a tarp or plastic sheeting under the wet area helps keep it from spreading into insulation and drywall. Note when the stain appears, during rain, right after, only in certain wind, or with the spring melt, since that pattern is genuinely useful when we trace the source. Stay off the roof yourself; a wet or icy roof is dangerous to walk and can make the damage worse.
How long the trace itself takes depends on how many potential sources sit on the affected slope, whether the roof is pitched or flat, how accessible the area is, and whether the attic side needs checking as well as the roof surface. The repair cost then depends on what is actually found: a failed seal is a small fix, a compromised flashing detail or storm-damaged section is a larger one. Because it varies that much house to house, pricing comes as a written scope once the source has actually been traced, not a number guessed over the phone.
You can gather useful information, note when the stain appears and under what conditions, and check the attic hatch for visible staining if you can safely reach it, but climbing onto the roof yourself is not something we would recommend. Roofs can be genuinely dangerous to walk, especially wet or icy ones, and an untrained eye can miss the actual entry point while focused on the visible symptom. The information you gather is still valuable, hand it to whoever traces the roof.
It rarely stays small. Water reaching the roof assembly can lead to framing and sheathing rot that spreads quietly behind drywall and insulation, insulation that loses most of its performance once wet, mould risk in wall cavities and ceilings, and stains or bubbling paint that keep reappearing after cosmetic fixes. The longer the source goes undocumented, the harder it can also be to support an insurance claim, so tracing it properly sooner rather than later tends to be the less costly path overall.
Tell us where the stain is and when it shows up. We’ll get back to you with a clear written scope, not a guess.
Serving: Calgary, Airdrie, Cochrane, Okotoks, Chestermere. Homes, commercial and multi-family properties.