RoofPRO Installs Flashing and GAF Royal Sovereign Shingles in Ellicott City, MD

How RoofPRO Found and Fixed a Hidden Valley Flashing Failure in an Ellicott City, MD Home

When an Ellicott City, MD homeowner noticed water dripping from their living room ceiling, the source was far from easy to find. The leak was located right where two roof slopes came together, with no attic access to inspect from below. Discover how RoofPRO measured and pinpointed the exact location from the roof surface, uncovered a combination of improper flashing installation and a low-slope design that made the area especially vulnerable, and fabricated custom black aluminum flashing to fix it the right way.

What Problem Did the Homeowner Face?

Water was dripping from the ceiling in the middle of the living space, and the drywall below had already sustained damage. The leak was positioned directly at the valley where two roof slopes met, and with no attic access available, there was no way to inspect the source from inside the home. RoofPRO measured the location of the leak precisely from inside so the exact spot could be identified on the roof surface above.

On the roof, the problem became clear. The metal flashing at the valley had been installed with nails placed directly through the face of the metal in an area exposed to the elements. Over time the nails had rusted completely through, compromising the flashing. Compounding the issue, the slope of the roof in that area was low enough that it made the transition even more susceptible to water intrusion, leaving very little margin for any installation error.

How Did RoofPRO Solve the Problem?

RoofPRO removed everything in the affected 2×4 foot area down to the plywood to assess the deck and correct every layer of the problem. Fortunately the plywood was still in good condition and did not need to be replaced. The work included:

• Precise measurement of the leak location from inside the home to pinpoint the exact area on the roof surface before any work began.
• Full removal of the failed flashing and surrounding shingles down to the plywood deck.
• Installation of ice and water shield underlayment across the entire area to provide a watertight base layer suited to the low-slope conditions.
• Fabrication of custom bent black aluminum flashing designed specifically for this valley transition, with all fasteners hidden so no nail heads would be exposed to the elements.
• Installation of GAF Royal Sovereign Weathered Gray three-tab shingles to complete the repaired area.

What Made the Velux FS Fixed Skylight the Right Fit for This Home?

Standard off-the-shelf flashing products are not always adequate for low-slope valleys where water moves slowly and has more opportunity to find any weakness in the installation. The custom black aluminum flashing RoofPRO fabricated for this transition was bent specifically to fit the geometry of this valley and installed in a way that kept every fastener completely hidden. This eliminates the failure point that caused the original flashing to fail and ensures the solution holds up under the same low-slope conditions that made this area so vulnerable in the first place. Black aluminum was selected to match the existing flashing profile on the rest of the home.

How Did This Project Help the Homeowner Reduce Risk and Long-Term Costs?

A less experienced roofer might have simply caulked over the rusted nails and called it done. But caulk is not a permanent solution at a flashing transition like this one. Water can still seep in from the sides of the flashing where the caulk doesn’t fully seal, and once the caulk begins to wear and crack, the leak returns. RoofPRO removed everything and corrected the installation at the source:

• Eliminated the failure point: Rusted, exposed nails and improperly installed flashing were fully removed and replaced with a custom fabricated solution with no exposed fasteners, removing the problem entirely rather than masking it.
• Upgraded the full assembly: The custom flashing and ice and water shield underlayment were selected and installed specifically to handle the 4/12 pitch conditions that made this transition especially vulnerable.
• Protected the interior: Catching the leak before it reached the plywood meant no decking replacement was needed, keeping the scope and cost of the project contained.
• Long-term value: Sealing the transition properly protects the living space below from any further water intrusion or drywall damage.

Could Your Home Have the Same Problem?

Valley flashings are one of the most critical transitions on any roof, and low-slope valleys are particularly unforgiving when installation is not done correctly. Because the flashing sits beneath the shingles, there is no way to know from the ground whether it was installed properly or whether the fasteners are beginning to rust. If your home has a valley where two roof slopes meet and you are seeing any staining on interior ceilings near that area, it is worth having a professional inspect the full transition before the damage works its way into your living space.