Chimney Flashing Leaks in Austin: Is It the Flashing, the Chimney or the Wall?
If you have a water stain on the ceiling next to a fireplace, or on a wall below the spot where a roof meets a second story, check the flashing first. Flashing is the metal that seals the joint where the roof stops and a chimney or wall starts. Water can also soak through the brick, a cracked chimney top or the siding, though, and those need a different fix.
Is the leak coming from the flashing or the chimney itself?
Where and when the water shows up tells you a lot:
A stain on the ceiling or upper wall beside the chimney that grows after a hard, wind-driven rain points to the flashing at the roof line.
Water in the firebox, a rusty damper, or dripping inside the chimney points to water getting in at the top: a missing cap, a cracked crown (the concrete top of a brick chimney) or a rusted chase cover.
Damp or flaking brick in the attic, above the roof line, can mean the masonry itself is taking on water. The Chimney Safety Institute of America (CSIA) says common brick acts like a sponge.
A stain on a wall below a lower roof edge, often near a window, points to a missing kick-out flashing.
If you can get into the attic safely, shine a flashlight on the wood around the chimney after a rain. InterNACHI, a home inspector group, has inspectors check there because stains or soft wood point to a leak at the roof line.
What does chimney flashing include?
According to the American Society of Home Inspectors (ASHI), a brick or stone chimney on a shingle roof needs several pieces working together:
Apron flashing across the bottom, lapped over the shingles.
Step flashing up each side, in short pieces woven in with each row of shingles.
Counterflashing over the top edge of those pieces, fastened to the chimney only, with its top bent into a groove cut into a mortar joint. That groove is called a reglet.
A back pan or cricket on the uphill side. A cricket is a small peaked section that splits water around the chimney. The 2021 International Residential Code requires one behind any chimney more than 30 inches wide.
Some homes have a factory-built fireplace instead. A metal flue runs up through a wood-framed box called a chase, topped with a sheet-metal chase cover. CSIA inspection guides call for checking that cover for rust, pinholes and low spots that hold water, along with the flashing where the chase meets the roof.
Why does caulk keep failing around my chimney?
Gray or black goop along the top of the metal can mean the counterflashing was never set into a reglet, or it has pulled out. ASHI calls a caulked or roof-cement joint there a temporary fix that needs ongoing upkeep. InterNACHI notes that sealant dries, shrinks and cracks.
Austin heat speeds that up. NOAA's 1991–2020 averages for Camp Mabry show about 123 days a year at 90°F or hotter. Fresh caulk can buy a dry season, but it won't correct counterflashing that was installed wrong.
What about where a roof meets a wall?
The same leak shows up where a lower roof runs into the wall of a second story or a dormer. The code calls for step or continuous flashing at least 4 inches tall and 4 inches wide along that wall, tucked behind the siding or covered by counterflashing on brick and stone.
Where the roof edge stops but the wall keeps going, the code also requires a kick-out flashing. This small angled piece sends water into the gutter instead of down the face of the wall. The Department of Energy's Building America program shows stucco damaged where one was missing. It warns that fiber cement, vinyl and brick veneer can hide that damage for years. With stone or brick veneer, water that gets behind the stone runs down a layer behind it, so the right fix can mean opening part of the wall.
Should you repair the flashing, re-flash it, or wait for a new roof?
Vantage Roofing bases the answer on what we find on your roof:
Loose counterflashing on sound metal: we reset it into the mortar joint, cutting a new reglet if needed, and seal it.
Rusted, bent or missing pieces, no cricket on a wide chimney, or no kick-out: we re-flash that area with new step flashing and counterflashing and add a cricket or kick-out where the code calls for one.
A roof near the end of its life: re-flash as part of the replacement so you don't pay for the same labor twice. The code says rusted, damaged or worn flashing must be replaced during a re-roof.
Water coming through the brick, crown, cap or chase cover: that's chimney or masonry work, not roofing. We'll show you photos and tell you plainly that new flashing won't stop it.
Census figures put Austin's median home at 1994, with about 57% of homes built before 2000. In older neighborhoods like Hyde Park and Travis Heights, we often find old chimney flashing, sometimes patched with roof cement. NOAA's storm records also list 121 reports of hail an inch or larger in Travis County and 163 in Williamson County from 2016 through 2025, so we check chimney and wall flashing on every storm inspection.
Vantage Roofing backs its work with a 10-year workmanship warranty on full replacements and up to 1 year on service repairs. If your leak started after a storm, our guide to finding a roof leak after rain in Austin covers other places water gets in.
Get your chimney flashing checked before the first fire of the season
Before the first fire of the season is a good time to catch a slow leak. Vantage Roofing inspects chimney and wall flashing across Austin, Round Rock, Georgetown and nearby towns. We get on the roof, check the attic when we can, photograph what we find and give you a written estimate. You can also request a free inspection online.
Frequently asked questions
Can I fix chimney flashing myself with sealant?
You can buy time, but sealant won't fix the cause. Sealant along the top of the metal dries out and cracks, and home inspectors treat it as a temporary repair. If the counterflashing was never set into the mortar joint, or the step flashing underneath is rusted, more caulk only covers the problem. The roof around a chimney is also a hard place to work safely, especially when it's wet.
How do I know if my chimney needs a cricket?
Measure the side of the chimney that faces the ridge, across the slope of the roof. The 2021 International Residential Code calls for a cricket or saddle on the uphill side of any chimney or other opening wider than 30 inches. Without one, water and leaves collect behind the chimney and sit against the flashing. We check for it on every chimney inspection.
Why is there a water stain on the wall under a lower roof?
Look outside where the lower roof edge meets the taller wall. If there's no kick-out flashing there, rain running down the roof can pour down the face of the wall and get behind the stucco, stone or siding. Stains often show up near a window below. Adding a kick-out may also mean repairing wet sheathing behind the wall first.
Does a new roof come with new chimney flashing?
It should. The building code says flashing that is rusted, damaged or worn has to be replaced during a re-roof, and flashing gets rebuilt to the shingle maker's instructions. Ask your roofer, in writing, whether the step flashing, counterflashing and any cricket will be new or reused. Old metal next to new shingles can leave the chimney as the weak spot on an otherwise new roof.
My fireplace is metal with a wood-framed chimney. Can that leak too?
Yes. A factory-built fireplace sits inside a framed chase with a metal cover on top. If that cover rusts or holds water, it can leak into the framing and down onto the fireplace. Flashing where the chase meets the roof can fail too. Rust streaks on the chase siding or rust inside the firebox are warning signs.
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