What gauge metal is used for a corrugated flat roof in Houston?
For corrugated metal roofing, most residential patio covers and carports use 26-gauge Galvalume or aluminum panels. Commercial and high-wind-exposure applications may call for 24-gauge for added rigidity against uplift.
Can corrugated metal roofing be installed on a truly flat structure?
No. Corrugated panels need continuous slope to shed water through the rib channels — a true zero-pitch deck requires a membrane system such as TPO or acrylic coating instead.
Why do corrugated panels rust first at the screws?
Fastener heads puncture the panel’s protective coating, and Houston’s Gulf humidity accelerates corrosion at that exposed point faster than on the flat panel surface.
How long do corrugated metal panels last in Houston’s climate?
Properly installed Galvalume corrugated panels typically perform 20-30 years, though coastal humidity and UV exposure can shorten that if fasteners aren’t re-torqued or resealed periodically.
Can polycarbonate corrugated panels be used instead of metal?
Yes, on patio covers where light transmission is wanted. Polycarbonate has a shorter service life than metal in direct Houston sun and yellows faster without a UV-stabilized coating.
What causes side-lap leaks on corrugated metal roofing?
Side-lap leaks usually trace to missing or degraded closure strips between overlapping rib profiles, allowing wind-driven rain to travel sideways under the panel during Gulf storms.
Do corrugated roofs need a permit in Harris County?
Structural roof work, including new patio cover or carport installations, generally requires a permit through Harris County Permits. Repairs and like-for-like panel replacement are typically exempt.
How is wind uplift resistance rated for corrugated panels?
Panel and fastener assemblies are rated to specific wind-uplift pressures under ASCE 7 and adopted by the International Code Council. We match fastener spacing to the structure’s exposure category rather than a flat default.
Can corrugated metal roofing be repaired instead of replaced?
Isolated rust or a single damaged panel can usually be cut out and replaced. Widespread fastener corrosion or repeated leaks across multiple panels typically points to a full re-panel.
Does ponding water void a corrugated roof warranty?
Standing water at end-laps beyond normal drainage time is generally treated as an installation or slope defect, and most manufacturer coating warranties exclude damage from chronic ponding.
What maintenance does a corrugated flat roof need?
An annual check of fastener torque, closure-strip condition, and debris buildup at end-laps catches most failures before they become active leaks — especially ahead of hurricane season.
Is corrugated metal roofing a good fit for a Houston patio cover?
Yes — corrugated metal is a common, cost-effective choice for patio covers and carports because it sheds Houston’s heavy rainfall quickly and handles high heat without the ponding risk of a low-slope membrane.






















