Roof Leak Repair — Pipe Boots, Valleys and Chimney Flashing
A brown ring on the ceiling, a drip down the furnace flue, water in the attic under a vent — we find where it gets in and fix that spot, not the whole roof.
JMB Builders does roof leak repair on asphalt shingle roofs across the Twin Cities metro. Most leaks are a detail, not the roof: a split pipe boot, a nail pop, a valley that lost its metal, or chimney step flashing that was caulked instead of woven in. We find the entry point, fix that detail with new flashing and shingles, and tarp it first when it is still raining. Priced per project, quoted from your photos within one business day.
- Priced per project, one leak or several
- Tarped first when the weather will not wait
- Quote from photos in 1 business day
- Licensed MN contractor BC809005
Water almost never comes in through the field of the shingles. It comes in where something pokes through the roof or where two planes meet: plumbing vent boots, bath fan caps, the chimney, skylights, the valleys, and the step flashing where a lower roof runs into a wall. The rubber on a pipe boot cracks after enough Minnesota winters. Chimney counter-flashing gets replaced with a bead of caulk that lasts two seasons. A valley gets a nail through the metal. Each of those is a half-day fix if someone finds it.
Finding it is the job. The stain on the ceiling is usually downhill from the entry point, sometimes by several feet, because water runs along the underlayment and the rafters before it drops. We go in the attic first when there is one, follow the water trail up to daylight or a wet spot on the sheathing, then go on the roof and lift shingles until we see the hole. We take photos of what we found before and after the fix and put them in your job folder.
When the leak is not a detail — shingles that crumble when you lift them, sheathing that is soft in more than one spot — we tell you that and quote a replacement instead. See the shingle roof replacement page.
What you supply
- Photos: the ceiling stain or drip, the outside of the roof above it, and the attic if you can get in
- The roof's age if you know it, and any previous repair history
- Access to the attic and a place to set up a ladder
What JMB supplies
- Attic and roof inspection to find the actual entry point, not just the stain
- New pipe boots, bath fan or plumbing vent caps, step and counter-flashing, valley metal as needed
- Matching shingles for the repair area, ice and water membrane under the new flashing
- A tarp, properly fastened, when it is still raining or the fix has to wait for a dry day
- Sealant only where sealant belongs — flashing does the work, not caulk
- Photos of what was wrong and what was done, in your job folder
How it is priced: per project
Quoted in writing from your photos within one business day. What moves the number:
- Pipe boot or nail pop (quick) vs. chimney or sidewall step flashing (shingles come off and go back on)
- Roof pitch and height — a walkable ranch roof vs. a steep two-story that needs roof jacks
- Whether sheathing under the leak is soft and has to be cut out and replaced
- How many leak points there are; the second one on the same visit is cheaper than the first
- Chimney work that needs a mason (crown, tuckpointing) is referred out
- Whether a temporary tarp is needed before the repair day
Send a photo of the ceiling stain and a photo of the roof from the yard showing the vents and chimney above it. The quote covers the most likely repair with a note on what changes it.
How long it takes
Pipe boot or single flashing repair: a couple of hours. Chimney re-flash or valley repair: half a day to a day. Tarp same or next day when it is raining.
How your project works
- 1
Send photos, get a written quote
Send three photos of the space and a sentence about what you want. You get a clear, itemized quote within one business day. We only come out to measure first when the job needs a tape measure — no pressure, no games.
- 2
Pick materials, or bring your own
We help you choose profiles and materials that fit the house and the budget, or match your existing millwork exactly — or you buy the door or trim yourself and we install it. Everything is confirmed before the crew is scheduled.
- 3
Clean, precise installation
The crew shows up on time, protects floors and furniture, and installs with tight joints and consistent reveals. Photos of the finished work go in your job folder.
- 4
Walkthrough and invoice
We walk the finished work with you. If anything is not right, we fix it before we call the job done. Then one invoice, paid by check or direct deposit — no card fees, no payment links.
Situations and options
Pipe boot and vent cap replacement
The rubber collar on a plumbing vent boot splits with age and sun. We lift the shingles above it, slide the old boot out, set a new one on ice and water membrane and re-shingle over the flange. Bath fan and furnace vent caps get the same treatment.
Chimney flashing
Proper chimney flashing is step flashing under each shingle course with counter-flashing let into the mortar joint over it. A caulked-on patch is what usually failed. We rebuild it that way, with a cricket behind wide chimneys so water does not pond there.
Valley repair
Open metal valleys rust through or get nailed in the center; closed-cut valleys wear at the cut line. We open the valley, lay new membrane and metal, and re-lace the shingles from both sides.
Sidewall step flashing
Where a lower roof meets a wall, each shingle course needs its own piece of step flashing tucked behind the siding or a kick-out at the bottom. Missing kick-outs rot the wall below. We pull the bottom siding courses, install the flashing and kick-out, and put the siding back.
Emergency tarp
When it is raining and the repair cannot happen safely, we tarp the area with the tarp run over the ridge and fastened to battens, not nailed through the middle. Then we schedule the repair for the first dry day.
Roof Leak Repair — Pipe Boots, Valleys and Chimney Flashing: questions, answered
Why is my roof leaking around the vent pipe?
The rubber collar on the pipe boot has cracked. It is the most common roof leak in Minnesota because sun and freeze-thaw break down the rubber long before the shingles are done. The fix is a new boot set on ice and water membrane under the shingles above it. It takes a couple of hours and does not require touching the rest of the roof.
Can you fix a roof leak while it is still raining?
We can stop it. Walking a wet roof to do finish work is not safe, so on a rainy day we get a tarp over the area, run it past the ridge so water cannot get under the top edge, and fasten it to battens rather than nailing through the field. The permanent repair happens on the first dry day. Send photos and we will tell you the same day whether a tarp is needed or the repair can wait.
How do you find where a roof leak is coming from?
From the attic first. Water stains on the underside of the sheathing or a dark streak down a rafter point uphill to the entry. Then on the roof, we lift shingles at every penetration and joint above that spot until we find the hole, the split boot or the missing flashing. The ceiling stain alone is a poor guide because water runs downhill along the underlayment before it drops.
Is a chimney flashing leak a roofer or a mason problem?
Usually a roofer problem. Step flashing and counter-flashing are roofing work, and a caulked-over patch is the most common failure. If the chimney crown is cracked or the mortar joints are open above the roofline, water gets into the brick itself and that is mason work; we will tell you which it is from the photos and refer the masonry out.
Should I repair the leak or replace the roof?
Repair it if the shingles around the leak are still flexible and holding their granules and the sheathing is sound. If shingles crack when lifted, curl at the edges or have bald spots across the roof, a repair buys a season and the money is better spent on replacement. We say which one it is after the inspection and quote both when it is a close call.
Will the repaired area match the rest of the roof?
It will be close, not invisible. New shingles in the same color are darker than shingles that have weathered for years. We use the closest current match and keep the repair as small as the leak allows. On a repair near the ridge or a valley the difference is hard to spot from the ground; on a front slope it is visible up close.
Get a written quote for this job
Three photos and a sentence is enough. You hear back within one business day. Or text the photos to 763-204-2099.
Related jobs we do
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Read morePage reviewed September 24, 2026 · JMB Builders LLC, MN license BC809005 · All roofing pages
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