What gutter guards work with a metal roof?
Short answer. Use gutter guards that attach only to the gutter, screwed to the front lip and fastened to the back of the gutter or the fascia, because metal panels cannot be lifted like shingles to tuck a guard underneath. Fine mesh with a rigid frame handles the fast, concentrated runoff from metal better than hood styles, which tend to let water overshoot.
Why under-panel guards are a bad idea
Metal panels are fastened through the face or held by concealed clips, with foam closures and sealant at the eave. Prying up a panel edge to slip a guard under it can bend the panel, disturb the closures and open a path for wind-driven rain. Many guard instructions written for shingle roofs simply do not apply to metal.
What to look for
- Gutter-only mounting. Front lip screws plus a back flange that fastens to the gutter's back wall or the fascia below the panel edge.
- Clearance. Leave room between the guard and the panel overhang so water drops from the panel onto the mesh instead of skipping past.
- Mesh, not hoods. Water leaves smooth metal fast. Mesh catches it across the full width; surface-tension hoods are more likely to overshoot in a downpour.
- Compatible metals. Use stainless or coated fasteners and avoid pairing copper with aluminum or galvanized parts.
- Strength. In the mountain counties, sliding snow and ice can crush lightweight guards. Snow guards on the roof above protect both gutters and guards.
Debris on metal roofs
Leaves and needles slide off metal more easily than shingles, which is good for the roof but means the gutter catches debris in bigger, faster batches after wind or rain. A guard that sheds debris over the front, instead of trapping it on top, keeps up better. Check corners where two planes meet, since that is where both water and debris concentrate. For background, read metal roofing in Georgia and gutter sizing and guards.