# Corrugated and R-panel metal roofing, installed like a roof, not a shed.

Mammoth Roofing & Exteriors · https://mammothroofs.com/services/metal-roofing/corrugated-metal/ · (210) 934-9074

The exposed-fastener panel is the honest workhorse of Texas roofing: barns, porches, workshops, ranch homes. Done properly — right screws, right closures, underlayment over a solid deck — it lasts decades. Done badly it leaks at every screw. We do it properly.

## Two profiles, two jobs.

- **R-panel**: The commercial and agricultural standard: 36-inch coverage, deep ribs, fast to install. Warehouses, barns, workshops and big simple roofs. Reflects heat; shrugs off wind and heavy rain.

- **U-panel / corrugated**: The residential profile: a cleaner, tighter wave for porches, ranch homes and additions. Lightweight, cost-effective, and it sometimes goes over an existing roof after an inspection.

- **Colors and finishes**: Galvalume bare, or painted in the standard color range with a finish warranty. Matching trim, ridge and closures in every color.

- **That's standing seam.** (Standing seam): If the roof is the front of the house and you want no screws on show, read the standing seam page first.

## What corrugated metal solves that shingles struggle with.

- **Heat**: Reflective panels keep the attic cooler than dark shingles, and metal doesn't soften or curl at 105°F.

- **Storms**: Interlocking panels screwed to the deck on the manufacturer's pattern handle wind and hail better than a three-tab shingle ever will.

- **Water**: Steep, smooth ribs shed water fast; the leak points are the screws, which is why the screws, washers and closures are the whole job.

- **Weight**: Light enough to go on almost any structure, including porches and additions that were never framed for tile.

## Six steps, no shortcuts.

The panel is the cheap part. The screws, closures and underlayment are why it doesn't leak.

- **Free inspection + Roof Grade**: Decking, structure, pitch and the existing roof, so we know whether it's a tear-off or an overlay.

- **Quote and color**: Panel profile, gauge, color, trim and every line item, in writing.

- **Deck and underlayment**: Rotten decking replaced per sheet; synthetic underlayment over the whole deck. Metal over bare purlins is for barns, not houses.

- **Panels**: Laid from the eave, lapped against the prevailing wind, screwed with the right washered fastener on the manufacturer's pattern.

- **Trim and closures**: Ridge, eave, rake and wall trim; foam closures at every panel end; sealed penetrations.

- **QualCheck**: The 26-point inspection, photos, SweepCheck for screws and offcuts, and the warranty document.

## Straight answers before you book.

### How long does corrugated metal roofing last?

Properly installed and maintained, 40 to 70 years or more. The finish and the fasteners are what age; both are replaceable.

### Can it be installed over my existing roof?

Often, on a single layer in sound condition after an inspection. We'll tell you when a tear-off is the better money.

### Is it energy-efficient?

Reflective panels reduce attic heat and cooling costs in summer; the effect is biggest with a light color and proper attic ventilation.

### What maintenance does it need?

Very little: keep debris off, check fasteners every few years, keep the gutters clear. We can put it on an annual tune-up.

### Is the inspection really free?

Yes — it's the same Roof Grade visit for every service. Attic first, 75–150 photos, the 32-point Hunter-Gatherer Report, a letter grade and a plain-English verdict. You get the written report whether you hire us or not.

### Will you tell me if I don't need the work?

Yes. An A grade is a handshake and a date to look again. A B means a few small repairs, priced in the open, on a roof with years left in it. We'd rather be the roofer you call in ten years than the one who sold you a roof you didn't need.

### What warranty comes with the work?

Repairs carry a workmanship warranty in writing on the invoice. Full replacements carry the Mammoth Two Tusk Limited Lifetime Warranty: our 10-year workmanship warranty on the installation, plus the manufacturer's lifetime material warranty on the materials, which means the life of that product on the manufacturer's written terms. Ask us for the warranty document and read it before you sign.