Water Running Behind the Gutter

Of everything a gutter can do wrong, this is the one to take seriously. An overflow dumps water on the ground where you can see it. Water going behind the gutter runs down the fascia, into the soffit, and sometimes into the wall, and it does all of that where nothing is visible until the damage is done.

The gap that should not exist

Look at how a roof edge is built. The shingles end. Below and behind them is the fascia board. The gutter hangs off that fascia. Between the bottom edge of the roof and the back of the trough there is a gap, and something has to carry water across it into the gutter.

That something is flashing: drip edge or gutter apron, a bent piece of metal that tucks under the roofing and extends out over the back of the gutter, so water leaving the shingles lands in the trough rather than tracking backwards.

When it works you never think about it. When it is missing, water follows the underside of the roof edge by surface tension, curls back, and runs down the face of the fascia.

The four ways it goes wrong

There is no flashing at all. Common on older installs. It was simply not fitted, or it was removed during a re-roof and never replaced.

The flashing is too short or fitted the wrong way. If it does not extend far enough to clear the back of the trough, water still gets behind. If it sits behind the gutter’s back edge instead of over it, it delivers water into exactly the wrong place.

The gutter has tipped forward. As fasteners loosen, the back of the trough drops away from the fascia and opens a gap the flashing can no longer bridge. This is why a gutter pulling away and water behind it usually turn up together.

Ice forced the gap open. A trough that froze solid can lever the run away from the house, which opens the gap for the rest of the year.

How to tell you have it

You will not see the water while it is happening. Look for what it leaves:

• A dark vertical stain on the fascia, usually strongest under a specific stretch.
• Paint bubbling or peeling on the fascia in a line rather than a patch.
• Soffit staining, sagging or a soft spot underneath.
• A gap you can see from the ground between the back of the gutter and the house.
• Wet ground very close to the wall after rain, well inside where an overflow would land.

The last one is a useful tell. Overflow water lands out from the house. Water running behind lands directly against the foundation.

Why this compounds

The loop is what makes this expensive. Water rots the fascia. Rotted fascia loses its grip on the gutter fasteners. The gutter tips further away. A wider gap lets more water behind. Each stage speeds up the next.

It also means the repair keeps growing. Caught early, this is flashing and re-securing a run. Left two or three seasons, it is flashing, fascia, and possibly the edge of the roof decking.

What Omaha housing adds

Freeze and thaw is the accelerant. Water sitting in soaked wood expands as it freezes, opening the grain and speeding up rot in a way that steady wet alone does not.

The metro’s older suburbs are the ones to check hardest. A large share of the inner ring was built in the late 1950s and early 1960s, when drip edge was not always fitted as standard. Those houses have also usually been re-roofed at least once, and a re-roof is a common point for flashing to go missing.

What the fix involves

Getting the flashing right, making sure the gutter sits tight to the fascia at the correct pitch, and checking the wood behind before anything gets screwed back into it. Re-hanging a gutter onto soft fascia guarantees a repeat.

We do handle fascia as part of a gutter replacement, since the run is off and the board is exposed at that point. What we do not do is standalone fascia or soffit work.

If you have staining on your fascia and are not sure how bad it is, get somebody to look before another winter. Estimates are free, with a $250 minimum on any job.