Common Roofing Issues: Roof Flashing That's Shifted

How to Repair Roof Flashing That's Shifted

A durable fix usually requires more than hammering roof flashing back down. In fact, if you do that the flashing may not be in the proper place. To restore proper drainage and keep water from penetrating past the roof surface you have to take steps to install roof flashing the right way. And it's something you want to do ASAP since new roof flashing costs a lot less than repairing structural damage and water restoration.

1. Inspect and Locate Where the Movement is Coming From

• Look for bent, lifted or wrinkled flashing around chimneys, sidewalls, dormers, skylights, valleys and roof edges. These are the areas most affected.
• Inside, check the attic and ceilings for stains, damp insulation, musty smells or darkened wood.

2. Carefully Lift Roofing Around the Affected Area

• Remove or loosen roofing materials around the shifted flashing so you can access it all the way.
• Check for signs of membrane shrinkage, rotted decking and damaged underlayment caused by continuous flashing leaks.

3. Evaluate the Flashing to Determine if it Will Be Reused or Replaced

• If the flashing is only slightly bent and still structurally sound with no cracks, holes or severe rust, you may be able to carefully straighten it and re-secure it.
• If the flashing is cracked, badly warped, corroded, too short or wasn't the proper flashing to begin with, replace it entirely rather than trying to repair it.

4. Reinstall Flashing Correctly

• Re-bend flashing to match the roof and wall angles so it sits flat without tension, which prevents it from wanting to spring up or shift again.
• Fasten the flashing in the correct locations so fasteners don't create leak paths. Follow proper step-flashing or counter flashing sequences at roof-to-wall and chimney details.
• Integrate flashing with shingles or the membrane in the right order, ensuring that water always flows from upper surfaces over lower ones, not behind them.

5. Seal and Restore the Surrounding Materials

• Use compatible, high-quality roofing sealant for added waterproofing.
• Replace any damaged shingles, underlayment or membrane, and reinstall the new material to match manufacturer and code requirements.
• Inside the structure, remove and replace any soaked insulation or mold-damage once you've confirmed the leak is resolved.

How to Prevent Flashing From Shifting in the Future

You can't control the local climate, but good flashing design, installation and maintenance dramatically reduce movement.

• Use Properly Sized, Quality Flashing: During roof repairs and replacement, ensure the metal thickness, width and type are appropriate for the roof and climate. Thin, undersized flashing is more likely to bend and shift.
• Control Roof Traffic and Debris: Limit foot traffic near flashing, train service trades where to step and keep branches or debris from scraping or piling against flashing edges.
• Regular Roof Inspections: Inspect flashing at least once a year and any time a major storm hits to look for movement, gaps, bent metal, corrosion and separated seams. Always address any issues promptly before they escalate.
• Watch For Structural Movement: In areas with expansive soils or settling foundations, keep an eye on cracks in walls and shifting roof lines. If you see changes, have the flashing checked too, since structural movement can pull it loose.

Flashing doesn't usually fail all at once. It usually starts by shifting just a little. Catching and correcting that movement early is one of the simplest ways to prevent big, expensive roof leaks later.

Not sure that your flashing is securely attached? LOA can provide a free inspection that will look specifically at the flashing's condition to determine the best course of action.