Installing Metal Roofing on a Shed: Step-by-Step DIY

Installing metal roofing on a shed comes down to five things done in order: confirm the slope suits an exposed-fastener panel, prep a sound deck or purlins, run underlayment and drip edge, screw the panels through the flats (never the ribs) with gasketed screws, and cap the ridge over foam closures. A one-slope 8×10 shed is a weekend job for one person with a drill and tin snips. Get the panel squaring and screw placement right and the roof lasts 40 years. Get them wrong and it leaks at the fasteners within a season.

This guide covers the exact sequence, the minimum slope your panel type needs, screw spacing math, and the mistakes that cause 90 percent of shed metal roof leaks.

Can you put a metal roof on a shed at your slope?

Yes, if the shed slope meets the panel’s minimum. Exposed-fastener corrugated and ribbed panels, the DIY-friendly choice for a shed, need at least a 3:12 pitch (3 inches of rise per 12 inches of run). Standing seam can go lower, down to 1:12 or even 0.5:12 with sealed seams, but it is not a screw-through DIY panel. Below 3:12 with corrugated panels, water backs up under the laps and finds the screw holes.

Most gable and lean-to sheds are built at 3:12 to 6:12, so a standard corrugated or R-panel install works. Measure your existing pitch before buying panels. If your shed is a low-slope flat-ish design under 3:12, use a low-slope membrane instead of exposed-fastener metal.

What materials and tools do you need for a shed metal roof?

You need panels sized to your slopes, gasketed screws, closures, trim, and a short tool list. For an 8×10 shed with a single slope, budget for roughly 3 to 4 panels at 3 feet coverage width each, plus ridge or wall trim. Buy panels cut to length so each run is one piece from eave to ridge, which eliminates end laps.

• Metal panels: corrugated or ribbed, cut to slope length. Panels cover about 24 to 36 inches wide after the overlap rib.
• Screws: #10 or #12 hex-head self-tapping screws with bonded EPDM rubber washers, 1 to 1.5 inches for wood purlins or decking.
• Underlayment: synthetic felt or a peel-and-stick membrane over solid decking.
• Closures: profile-matched foam or butyl closure strips for the eave and ridge.
• Trim: drip edge, ridge cap, and gable/rake trim.
• Tools: cordless drill with clutch, tin snips or nibbler, tape measure, chalk line, and safety glasses.

Cutting the panels cleanly matters. A circular saw with an abrasive blade throws hot metal filings that rust the coating. See our guide on how to cut metal roofing for clean-edge methods that protect the finish.

Do you need decking, or can panels go on purlins?

Both work on a shed. Exposed-fastener panels are stiff enough to span open framing, so many sheds run panels directly over horizontal wood purlins (2x4s laid flat across the rafters, spaced 24 inches on center). This is the cheapest method and skips decking and underlayment. Solid decking (OSB or plywood) with underlayment costs more but adds rigidity, a moisture layer, and a walkable surface.

Use purlins for a basic utility shed. Use decking plus underlayment if you want a finished interior, condensation control, or plan to store anything moisture-sensitive. On solid decking, always run underlayment, because bare metal over wood sweats and drips inside. Metal roof condensation is a common shed complaint; our metal roof condensation guide covers the vapor-control fixes.

How to put a metal roof on a shed, step by step

Work eave to ridge, one panel at a time, keeping every panel square to the first. The full sequence takes one person a half to full day on a small shed. Do not walk on installed panels more than necessary, and step only on the flats over a purlin or rafter.

1. Inspect and prep the frame. Check rafters and top plates for rot or racking. Sister any soft rafter with a matching board. The frame must be square and solid before panels go on.
2. Add decking or purlins. Fasten OSB decking, or install 2×4 purlins flat across the rafters at 24 inches on center, with one purlin at the eave and one at the ridge.
3. Run underlayment (decked roofs). Roll synthetic underlayment from the eave up, overlapping horizontal seams 4 to 6 inches, and staple it down. Skip this only on open-purlin installs.
4. Install drip edge at the eave. Nail drip edge along the lower edge every 12 to 16 inches so panel runoff sheds into the gutter or off the edge, not behind the fascia.
5. Set eave closure strips. Lay profile-matched foam closures on the eave line so the corrugation gaps are sealed against wind-driven rain and insects.
6. Square and fasten the first panel. Start at the end away from the prevailing wind. Overhang the eave by about 1 to 1.5 inches. Check square with a chalk line down the roof, because the first panel sets the line for every panel after it.
7. Screw through the flats. Drive gasketed screws in the flat pans next to the ribs, not through the raised ribs. Space them roughly 12 inches on center at each purlin or rafter line, and 6 to 9 inches on center along the eave and ridge edges.
8. Overlap and continue. Lap each next panel over the previous by one full rib, running the lap away from the prevailing wind. Fasten through both layers at the overlap rib.
9. Trim gable and rake edges. Snip panels to length at the rake and cap them with gable trim screwed every 12 to 16 inches.
10. Set ridge closures and ridge cap. Lay foam closures along both sides of the peak, then screw the ridge cap through the panel high ribs on both slopes so the cap seals the peak.

Where do the screws go, and how many?

Screws go through the flat pan of the panel, seated snug but not crushed, at 12 inches on center in the field and 6 to 9 inches on center at edges and laps. Driving through the flat keeps the fastener below the water line so the gasket seals; a screw through a rib sits in the runoff path and leaks. A typical shed panel run takes 20 to 30 screws.

Set your drill clutch so the rubber washer compresses flat but does not squeeze out past the screw head. An over-driven screw dimples the panel and breaks the seal; an under-driven screw leaves a gap. Both leak, and over-tightening is the single most common DIY mistake.

Can you install metal roofing over an existing shed roof?

You can install metal panels over old shingles or roll roofing on a shed, and it is common because it skips the tear-off. Run purlins or furring strips over the old surface to create a flat, screwable base and an air gap. For a small utility shed the weight and inspection stakes are low, so overlay is usually fine, unlike a house where a tear-off is often the better call.

The tradeoff: you cannot inspect the deck underneath, and any rot keeps spreading under the new metal. If the existing shed roof is soft, sagging, or leaking, tear it off first. The overlay-versus-tear-off logic mirrors full-house reroofing, covered in our metal roof installation guide and corrugated metal roofing guide.

Common shed metal roof mistakes to avoid

Most shed metal roof leaks trace to four errors, all preventable. Fixing them after the fact means backing out screws and reseating panels, so get them right on the first pass.

• Screws in the ribs, not the flats. Rib screws sit in the water path and leak. Always fasten through the flat pan.
• Over-tightening. A crushed washer or dimpled panel breaks the seal. Use the drill clutch and stop when the washer sits flush.
• First panel out of square. If panel one is crooked, every panel after it drifts. Chalk a line and check square before fastening.
• No closures or missing underlayment. Open corrugation gaps at the eave and ridge let in rain, wind, and wasps, and bare metal on decking sweats without underlayment.

Report your slope and panel type at the supplier so the closures match your profile; a foam strip cut for R-panel will not seal a corrugated wave.

Reviewed by The Roofing Brief Team. Last reviewed July 2026.