At a glance: Completed 2026-09-08: brick ledge flashing leak repair on Lennox Drive, Ballwin, MO 63011. Office: St. Louis, 314-429-6000.
A leak that was not coming from the roof
Not every leak is a roof leak. On Lennox Drive, water was showing up inside along the left elevation, and the source was the transition between the brick wainscot and the siding above it. Many two-story homes in west St. Louis County are built with brick on the lower part of the wall and vinyl siding above. Where they meet, the top of the brick forms a ledge, and that ledge is usually capped with bent aluminum trim.
When that cap is installed flat, or slopes slightly toward the house, rain running down the siding lands on it, pools and runs back toward the wall instead of off the face of the brick.
Finding the real cause
Water was getting behind the aluminum flashing on top of the brick and running down inside the wall. The cap had no positive slope, meaning it did not tip outward. Over years, settling and sagging can flatten a cap that was once barely pitched, and every storm sent water in.
Taking the wall apart carefully
To get at the cap, the crew removed the bottom course of vinyl siding along the brick and about 30 linear feet of J-channel, the trim piece that holds the cut edge of the siding. Vinyl siding unlocks from the course above with a zip tool, so it can be removed and reused without damage. Then the old trim metal was pulled off the brick ledge.
A half-inch shim for positive slope
The heart of the repair was a half-inch spacer installed along the back of the ledge, against the wall. When the trim metal goes back over it, the back edge sits half an inch higher than the front. That small tilt sends water forward, off the face of the brick, instead of back into the house. It is a simple detail, and it is the one that was missing.
Sealing every joint
The trim metal was reinstalled over the shim, and every joint and seam in the metal was sealed with white quad sealant, a high-grade elastomeric caulk that stays flexible and bonds to aluminum and vinyl. Joints in long runs of trim are a common entry point, so each one got attention, not just the obvious gaps.
Putting the siding back
With the cap sloped and sealed, the J-channel was reinstalled and the bottom row of siding was locked back into place. From the yard, the wall looks the same as before. The difference is under the surface, where water now runs the right way.
A roof check while we were there
The work order also called for checking the roof while the crew was on site, to make sure there was not a second source of water. Gutters overflowing onto the wall, a missing kick-out flashing at a roof edge, or loose step flashing above a wall can all send water down the same path. Ruling those out is part of a proper leak repair.
Brick-to-siding leaks in Ballwin homes
We see this same detail fail on homes all over Ballwin, Manchester, Ellisville and Wildwood. Signs include stained drywall near the floor on an exterior wall, swollen baseboards, musty smells in a lower-level room and white mineral streaks on the brick below the cap. If you see any of those, the ledge flashing is worth checking.
Roofer near me in Ballwin, 63011
If you are searching roofer near me in 63011, our St. Louis crews handle roof leaks, wall flashing, siding and gutters in one trip. Call 314-429-6000 or 1-800-564-6232 any time.
We will find where the water is actually getting in before we recommend anything.
Lifetime workmanship warranty
The flashing repair on Lennox Drive is covered by our lifetime workmanship warranty on the work we did.
Why the cap was flat in the first place
When a house is built, the trim installer often bends cap flashing to sit tight on the brick with no shim, because it looks clean. Over time the brick and framing settle, and a cap that started dead level can tilt slightly back toward the wall. It only takes a sixteenth of an inch of backward slope for water to collect there. Adding the half-inch shim gives enough tilt that small amounts of settling will not reverse it again.
What happens if a ledge leak is ignored
Water that gets behind the cap soaks the wood sill plate and the bottom of the wall framing. Over a few years that leads to rot, mold in the wall cavity, and damage to drywall, carpet and baseboards on the inside. Termites are also drawn to wet wood near the ground. Fixing the flashing early is far cheaper than opening the wall later to replace rotted framing.
Siding, gutters and roofing from one crew
Because John Beal Roofing handles roofing, siding and gutters, the homeowner did not need separate contractors to take the wall apart, fix the flashing and put the siding back. One crew did all of it in a single visit.
Testing after the repair
Once the siding was back, the crew checked that water poured onto the siding above ran forward off the cap and down the brick face, not back toward the wall.
What the crew did, step by step
- Removed the bottom course of vinyl siding along the brick ledge on the left elevation.
- Removed about 30 linear feet of J-channel.
- Removed the aluminum trim metal capping the top of the brick.
- Installed a half-inch shim spacer along the back of the ledge to create positive slope.
- Reinstalled the trim metal over the shim.
- Sealed all joints and seams in the trim metal with white quad sealant.
- Reinstalled the J-channel and bottom course of siding.
- Checked the roof above for any other source of water.
Questions homeowners in Ballwin ask about this repair
Why is water coming in where my brick meets siding?
Often the metal cap on top of the brick is flat or slopes toward the house, so water runs back into the wall.
What is positive slope on flashing?
It means the flashing tips away from the house so water runs off instead of back toward the wall.
Can vinyl siding be removed and reused?
Yes. Vinyl siding unlocks with a zip tool and can be reinstalled without damage.
Is a wall leak a roofing problem?
Sometimes. Roofers deal with flashing at walls every day, which is why we handle these leaks.
Do you do leak repair in Ballwin?
Yes. Call our St. Louis office at 314-429-6000.
What sealant did you use?
White quad sealant, a flexible elastomeric caulk that bonds well to aluminum and vinyl.