Exposed Step Flashing After a Cedar Shake Tear-Off: The Right Sidewall Fix

Here is a detail most homeowners never think about until the day their new roof is finished and they are standing in the yard looking at it: exposed step flashing along the sidewalls.

When we tear off a cedar shake roof, there is a spot where the roof meets the siding on every sidewall—along dormers, second-story walls, and anywhere siding runs down to the roofline. Shake roofs are thick. Once those shakes come off and the new, lower-profile shingle roof goes on, the individual pieces of step flashing—often called step tins by roofers—can end up exposed. Bare metal, staggered up the roofline, right where your eye lands.

It is not a leak. It is not a code violation. But it is ugly, and on a brand-new roof, ugly is the last thing you paid for.

Why Step Flashing Becomes Exposed After a Cedar Shake Tear-Off

Cedar shakes sit high — the shakes themselves plus the skip sheathing under them add real thickness to the roof plane. Your siding was originally cut to meet that thicker roof. When the shakes come off and a modern shingle system goes down, the new roof surface sits lower than the old one. The siding is now hanging above the roof with a visible gap, and the new step flashing is sitting there in plain view.

Some crews shrug and leave it. Some caulk it and hope you do not look up. Neither is finishing the job.

The Wrong Ways to Fix It

We have seen all of these on Twin Cities homes, and every one of them creates a problem worse than the one it hides.

Cutting the siding down to the roof. This closes the gap visually, but now the cut ends of your siding are sitting directly on the roof surface — exactly where water runs during every rain and sits during every snow melt. Wood and engineered-wood siding ends can absorb moisture when they are left against the roof surface. In Minnesota, with our freeze-thaw cycles, that is how you get rotted siding, swollen ends, and peeling paint within a few seasons. That is why siding manufacturers commonly require clearance between the siding and the roof surface.

Caulking the gap. Caulk is not flashing. A caulk-only fix is unreliable because the materials continually move through Minnesota’s temperature swings. When it fails, water goes where you cannot see it.

Just painting the step flashing. Better than nothing, but field-painting galvanized flashing rarely holds, and it does nothing about the gap or the siding clearance.

How We Do It

After the shakes are off and the roof replacement is complete, we fabricate custom sidewall flashing on site from aluminum coil stock. We bend the coil so it is doubled over — twice the thickness of a single layer. The doubled profile adds rigidity and greatly reduces oil-canning, denting, and rippling compared with a single layer of coil stock, and it keeps the flashing line dead straight along the roofline.

That double-strength flashing is installed directly over the step flashing. The upper leg is tucked behind the siding, while the finished lower face laps over the exposed step flashing. Here is what that accomplishes:

• The step flashing disappears from view. One clean, continuous line of finished metal along the sidewall instead of exposed staggered pieces.
• The siding keeps its clearance. The cut ends of the siding sit above the flashing with enough gap that they are never in contact with the roof surface where water can run and sit. Water sheds down the flashing and onto the roof — away from the siding ends.
• It is color-matched. Aluminum coil comes in dozens of finishes, so the flashing blends with your siding or trim instead of announcing itself.
• The step flashing underneath still does its job. We are not replacing the waterproofing layer — we are covering and protecting it. The step flashing keeps weaving water out of the wall-to-roof joint the way it is designed to. The cover flashing is the finished, weather-shedding face over the top.

It is the same logic as counterflashing on a chimney: the layer underneath handles the waterproofing, the layer on top handles weather and appearance. Both matter.

Why Roof-to-Siding Clearance Saves You Money

The aesthetic fix is what you notice from the driveway. The clearance is what you will appreciate ten years from now.

Siding that touches the roof fails early — full stop. Siding manufacturers commonly require clearance above roofing. LP SmartSide, for example, requires a minimum 1-inch clearance between the siding and the roof surface. When we bend our sidewall flashing, maintaining that clearance is built into the profile. The flashing gives the siding a proper place to terminate without leaving raw, exposed cut ends hanging over bare roofing.

If you are re-siding at the same time as the roof, this is even easier to get right — we set the new siding height off the finished flashing from day one.

What to Ask Your Contractor

If you are getting bids on a shake tear-off, ask one question: “What happens at my sidewalls where the siding meets the roof?”

If the answer is a blank stare, caulk, or “we will cut the siding down flush,” keep looking. The right answer involves properly integrated step flashing, a finished cover flashing over it, and the manufacturer-required roof-to-siding clearance. It takes an extra step and a metal brake on site — which is exactly why plenty of crews skip it.

We have been installing roofing and siding on Twin Cities homes since 2001, and details like this are the difference between a roof that looks good the day it is finished and one that still looks good — and keeps water out — twenty years later.

Have a shake roof you are thinking about replacing? Request a free roofing and siding estimate and we will walk your sidewalls with you and show you exactly what we would do. No pressure, just an honest look.

Related from Northern Exteriors

Flashing problems usually surface during a siding tear-off. Learn more about siding repair and replacement in Woodbury MN, or browse LP SmartSide color options before you pick a new look.